Micro Turbine III

Microturbine III Senior Design 05002Micro Turbine IIISenior Design Project 050021 Microturbine III Senior Design 05002Preliminary Design ReportDesign Team:Lincoln CummingsJoseph CalkinsMark FazzioAllison Studley2 Microturbine III Senior Design 05002Executive Summary:This report discusses in detail the work done by the Micro Turbine III design team throughout the design process thus far. The objective of the design project is to scale down the size of the system for implementation onto a Micro Air Vehicle (MAV). The parameters are that the micro turbine generator is to produce 5 watts of continuous power, have a system weight under 45 grams, and sized to fit within a MAV. The goals, procedures, analysis and other aspects of the design process are discussed throughout this technical paper. Much of the research and development of a feasible Micro Turbine design has been previously completed by the 04013 senior design team from last year. AMiniature Turbine is a feasible replacement for the current battery power on the RIT-MAV. Although last year’s design proved to provide enough power for all of the electronics on the MAV, the overall design was much too large to be implemented into the MAV airframe. By creating a Micro Turbine system which has advantages over the current battery power supply such as higher power to weight density, and decreased costs, the capabilities of the MAV can substantially increase. In order to provide as many possible improvements upon the previous design, new concepts were brainstormed, developed, and investigated further. Comparisons between the previous research and these concepts were made in several dimensions.Aspects such as weight, size, cost, availability, and ease of production were used to compare the different concepts and determine their feasibility. As a result of these comparisons, it was determined that the previous turbine design was most feasible due to time constraints, limited man power and a fixed budget. Other aspects of the design such as the fuel canisters, housing, fuel supply system, and also use of exhaust gases for3 Microturbine III Senior Design 05002 reducing the drag on the plane were either newly designed or modified from last year’s design. The design of the Micro Turbine III was done through the use of the EngineeringDesign Process which consists of twelve different facets. Only six of the facets were used in the development of the preliminary design and are discussed throughout this document. Each of these facets is contained in its own chapter, which discusses the facet in detail.Through the use of the Engineering Design Process, a new Micro Turbine design was developed that allows the system to be implemented into the MAV airframe. By using aspects of the previous designs along with some newly developed concepts, the system was not only made more compact, but may also possibly decrease the drag on theMAV. These designs and concepts must now be validated through the development of prototype systems which can be tested and analytically compared to the theory.4 Microturbine III Senior Design 05002Table of ContentsExecutive Summary:...... 3 1.0 Recognize and Quantify the Needs...... 7 1.1 Mission Statement...... 7 1.2 Project Description...... 7 1.3 Scope Limitations...... 8 1.4 Stakeholders...... 8 1.5 Key Business Goals...... 9 1.6 Top Level Critical Financial Parameters...... 9 1.7 Financial Analysis...... 10 1.8 Preliminary Market...... 10 1.9 Secondary Market...... 11 1.10 Order Qualifiers...... 11 1.11 Order Winners...... 12 1.12 Innovation Opportunities...... 12 1.13 Background Research...... 12 1.14 Formal Statement of Work...... 15 1.15 Organizational Chart...... 17 2.0 Concept Development...... 17 2.1 Subgroups...... 17 2.1.1 Housing Team...... 18 2.1.2 Turbine Team...... 18 2.1.3 Fuel System Team...... 18 2.2 Housing Concepts...... 19 2.2.1 Bearings...... 19 2.3 Turbine Concepts...... 20 2.4 Fuel System Concepts...... 20 2.4.1 Fuel...... 21 2.4.2 Tubing & Connectors...... 21 2.4.3 Flow Regulation...... 22 2.5 Generator ...... 23 3.0 Feasibility ...... 24 3.1 Turbine Feasibility...... 24 3.2 Housing Feasibility...... 25 3.3 Bearing Feasibility...... 26 3.4 Fuel System Feasibility...... 27 3.4.1 Fuel Feasibility...... 27 3.4.2 Tubing Feasibility...... 28 3.4.3 Flow Regulation Feasibility...... 28 4.0 Objectives and Specifications...... 29 4.1 Objectives...... 29 4.2 Performance Specifications...... 29 4.3 Design Practices...... 30 4.4 Safety Issues...... 31 5 Microturbine III Senior Design 050025.0 Design Analysis & Synthesis...... 32 5.1 Turbine Analysis & Synthesis...... 32 5.2 Housing Analysis & Synthesis...... 34 5.2.1 Housing FEA Analysis...... 35 5.2.2 Shaft Selection & Analysis...... 36 5.2.3 Bearing Selection...... 37 5.2.4 Coupling Selection...... 37 5.3 Fuel System Selection & Analysis...... 38 5.3.1 Fuel Selection...... 38 5.3.2 Tubing & Connectors Selection...... 38 5.3.3 Flow Regulation...... 39 5.3.4 Fuel System Analysis...... 39 6.0 Future Plans ...... 41 6.1 Test Setup...... 41 6.2 Schedule ...... 42 6.3 Budget ...... 43 7.0 Conclusion ...... 414 A. Appendix A – Turbine Performance Graphs...... 46 B. Appendix B – Turbine Performance Data...... 49 C. Appendix C – Mass Flow Calculation D. Appendix D – Finite Element Analysis On Housing / Cap...... 57 D. Appendix D – Finite Element Analysis On Housing / Cap...... 58 E. Appendix E – Turbine Performance Data...... 63Figures, Tables, and Equations Page Title 13 Fig 1-1: Capstone Micro Turbine 14 Fig 1-2: MIT's Micro Turbine & Test Stand 17 Fig 1-3: Organizational Chart 19 Fig 2-1: Housing Concept 20 Fig 2-2: 3-D Pelton Wheel Turbine 33 Fig 5-1: Blade 33 Fig 5-2: Turbine Design 35 Fig 5-3: Cap FEA 36 Fig 5-4: Housing FEA 42 Fig 6-1: Schedule 43 Fig 6-2: Budget25 Table 3-1: Housing Feasibility 26 Table 3-2: Bearing Feasibility33 Eqn 5-1: Blade Calculation 34 Eqn 5-2: Torque 34 Eqn 5-3: Efficiency 40 Eqn 5-4: Density 40 Eqn 5-5: Velocity 40 Eqn 5-6: Mass Flow 6 Microturbine III Senior Design 050021.0 Recognize and Quantify the Needs1.1 Mission StatementThe purpose of the 05002 Senior Design team is to design and build a working prototype of a micro-turbine generator that can be integrated into a MAV airframe and power the vehicles electrical accessories. The micro-turbine design is to be a continuation and improvement upon the previous design team’s project through the use of much of the previous research and design along with new research and design to create a baseline for integration into the MAV airframe. 1.2 Project DescriptionThe current RIT MAV vehicle’s motor and electronics are powered by a heavy and expensive Lithium Ion battery. Although these batteries supply the proper electrical capabilities, it has been proven through previous research and senior design teams that a more lightweight and compact power supply is feasible. The scope of the current project is to improve upon the previous year’s designs and to implement the design into theMAV airframe, which has not been done by previous teams. As a result of last year’s senior design team, there is an existing Pelton wheel turbine design which can be used in this years design. Other turbine designs, as well as other Pelton wheel designs will be investigated and their feasibility will be determined compared to the current design. Last year’s design produced the necessary power requirements, however was much too large to be implemented into the MAV airframe.This year’s team will research different turbine designs, propellants, and other components and evaluate their feasibility and advantages/disadvantages over the current7 Microturbine III Senior Design 05002 design. One of the major goals is to make a smaller housing which will be able to fit into the MAV airframe as well as be lightweight, robust, and fulfill the required power and flight requirements. The MAV requires a minimum of 5 watts of power for use by the onboard electronics. In order to achieve these power requirements, the turbine must rotate at high speeds, which last year’s team determined to be around 100,000 rpm.While designing the new system, the overall weight goal of 45 grams must be considered.1.3 Scope LimitationsThrough previous senior design research, it has been determined that a minimum of 5 watts of power is needed in the flight of the RIT MAV. This requirement sets a limitation on the micro turbine to produce a minimum of 5 watts of power for sustainable flight. As mentioned previously, the weight of the system is also an issue to improve upon the current battery power. A goal of an overall weight including propellant tanks is a reasonable 45 grams. Many of the limitations to research and design parameters are due to the limited amount of time as well as a project budget of $1000 - $1500. The budget is to be supplied by the Kate Gleason College of Engineering. 1.4 StakeholdersThe primary stakeholders in this design project are the members of the design team. In addition to these persons is the faculty of RIT’s Mechanical EngineeringDepartment. Dr. Jeff Kozak, the teams advisor and contact, is the dominate member of the faculty who will benefit from this year’s project in advancing the design onto future micro turbine design teams along with MAV teams.8 Microturbine III Senior Design 05002Secondary stakeholders include the outside venders sought for the manufacture of intricate parts. Also on this list are faculty and staff of other RIT departments including the Microelectronics Department and those in the Brinkman Laboratory. Stakeholders extend onto member of other current and future MAV design teams at RIT and other schools involved in micro turbine research. 1.5 Key Business GoalsA successful project will be defined by the evidence of a working micro turbine prototype producing five watts of power, weighing less than 45 grams, and sized to be implemented onto a MAV. If the design team is capable of completing the task, then much will have been accomplished. Not only will the core objective of the project be achieved, the students on the team will have also gained a valuable experience in working with a multidisciplinary team. The results of this project will serve as a stepping stone for further development in this field. Success of this project will bring future research a step closer to replacing the power source on MAVs, which is the ultimate goal.1.6 Top Level Critical Financial ParametersAlmost all of the budget will be used for purchasing of raw materials or sub- assemblies. The goal is to have the micro-turbine design be within a reasonable amount of a battery powered system. The prototype will use nitrogen gas in large canisters, the goal for future micro-turbine teams is to shrink the weight and size of the nitrogen canisters and piercing components so that they can be incorporated onto an MAV airframe.9 Microturbine III Senior Design 050021.7 Financial AnalysisThe project has a tentative budget of $1000 from the Mechanical Engineering department at RIT. This will be used to fund purchases of all the components listed in the Bill of Materials (see appendix XXX). The major components that will be ordered are the following: Housing material Fuel canisters Puncture system for the fuel canisters Turbine Internal components: shaft, bearings, couplings Machining costs: housing1.8 Preliminary MarketThe project team two years ago conducted a proof of concept project, while last year’s team designed a functioning prototype. That project initiated a host of long-term research projects. Therefore, the work being done is still set in the research realm while concern for actual implementation onto an MAV is under heavy scrutiny. The primary customer for this year’s project remains academia. Eventually these efforts and research will develop into a feasible energy source that the RIT MAV team can utilize for efficient flight.10 Microturbine III Senior Design 050021.9 Secondary MarketThrough added time and research, this design could be developed into a reliable source of lightweight energy production. There are numerous applications for such products. The Department of Defense (DoD) and the Forest Service are currently interested in utilizing MAVs for their particular needs. The DoD is interested in usingMAVs in military conflicts for ground personnel to utilize as scouts or forward observers.The Forest Service would like MAVs to fly into and around forest fires and monitor their status to help better direct fire fighting efforts. However, the product is not limited toMAVs. This lightweight energy production is open to a host of other applications.Micro robots that could be made lighter and smaller using micro turbines are a good example of this. The micro turbine is open to numerous applications in the future. 1.10 Order QualifiersThe purpose of this research design is to improve upon the technology that has already been produced at RIT. Therefore, the senior design team must produce a prototype micro turbine/generator system that is sized to be more suitable for MAV application than last year’s design in addition to including the fuel system into the design.To be more useful, the power produced shall be reduced from 18 W to 5 W. This is the power required by a MAV flight production. The weight must also be held to less than45 grams. This will make the product more feasible for MAV application.11 Microturbine III Senior Design 050021.11 Order WinnersIf time and money permit the team will work to complete the following goals: Implement the fuel system into the design.  Optimize turbine efficiency. Maintain the ease of assembly and disassembly of the turbine/generator system.  Improve bearing setup and design.  Improve the housing design to better fit an MAV.  Be safe to users and environment.  Validate data using Computational Fluid Dynamics modeling.  Design and test all components for form and function.1.12 Innovation OpportunitiesIn this day and age, persons in all industries are looking to maximize efficiency while minimizing the materials required. Micro turbines strive to achieve the same goal in providing an alternate power source. Since everything is on the micro scale, the complete package will be light in weight and compact in sized. Research in these turbines will aid any electrical required applications limited by space and weight. 1.13 Background ResearchThe term micro turbine has become undefined as its definition changes from field to field. It can be used to describe a stand-alone unit producing hundreds of kilowatts in industry to a Micro Electrical Mechanical System (MEMS) producing milliwatts of power in academic institutions. A wide range of applications in industry see the potential12 Microturbine III Senior Design 05002 for micro turbine generators for electricity. The primary use for micro turbines is in the growing Unmanned Aerial Vehicle (UAV) and model airplane markets. Institutions throughout the country are currently designing micro turbines on the micrometer scale. The high efficiency of micro turbines has led industry to scale down power producing turbines from thousands of megawatts to tens of kilowatts. CapstoneTurbine Corporation remains the world leader in the micro turbine market since introducing their products in1998. These highly efficient turbines are used for everything from hybrid electric vehicles (HEVs) to providing power to hotels and office buildings. By Fig 1-1: Capstone Micro Turbine utilizing a wide variety of fuels, these generators are able to be used in remote locations. In the commercial market, micro turbines are generally aircraft turbines scaled down to be sized appropriately. These turbines produce just a few pounds of thrust sufficient for UAVs, Missiles, and remote controlled aircraft. The continuous growth in the autonomous missile and UAV markets is being pushed by the military. NASA and the defense department hold numerous contracts for research and production of micro turbines. Unfortunately, these micro turbines are too large for MAV applications. Research is being conducted at universities throughout the nation and around the world. This research is on the scale in which RIT has been performing its work on the topic. A number of institutions are furthering research in the realm of power production on the milliwatt scale to a few watts. MIT is the currently leader in this field. Other work is being done at Stanford and Simon Fraser University. The work being done at each of these institutions is of a different nature. 13 Microturbine III Senior Design 05002MIT is leading the micro turbine research market due to their heavy funding provided by the Defense Advanced Research Projects (DARPA) along with other defense agencies. Due to this fact, much of their work remains unpublished while it is in the development stages. Figure 1-3 represents the radial flow reactive compressor, combustor and turbine system being developed by MIT. The greatest difficulty with this design is in the bearings, which are unable to withstand the high rotations per minute.The goal of this project is to produce approximately ten to twenty watts of power based on liquid hydrogen fuel. Alternative fuels such as hydrocarbons could produce up to a hundred watts of power.Fig 1-2: MIT’s Micro Turbine & Test StandStanford and Simon Fraser University are focusing their work on new manufacturing techniques to be used to produce highly specialized turbines. Stanford is developing a Mold Shape Deposition Manufacturing (Mold SDM) process to produce complex silicon nitride parts. While they have not testing a compressor and turbine system, compressed gas testing has proven the turbine to be successful up to 456,00014 Microturbine III Senior Design 05002 rpm. Figure 1-4 shows an example of some of the Stanford’s designs. Simon FraserUniversity is using a design already tested in nuclear magnetic resonance (NMR) spectroscopy of solid samples. Using this technology, impulse radial inflow turbines were produced in sizes ranging from 10-2.2 millimeters in diameter. Samples of these spun by compressed nitrogen have shown to function up to 1,000,000 rpm. The research and development at RIT began just three years ago with a proof of concept senior design project. During this project, headed by Dan Holt, a dentist drill was used to spin a generator. Holt continued the project on with his master’s thesis, in which he expanded into the realm of using a compressed gas to drive a turbine which in turn spins the generator. Last year’s design team continued the efforts of Holt by designing and producing a functioning micro turbine generator. This design was a great achievement for RIT in developing a usable design for Micro Air Vehicle (MAV) applications. However, the prototype from last year remained too large and heavy for use on a MAV. In addition, the fuel system was not included in the design. The current project described within this report aims to reduce the size and weight of the system, as well as implementing the fuel storage and delivery system into the overall design.1.14 Formal Statement of WorkThe Micro Turbine III Design Team shall produce a micro turbine/generator system fitted for implementation onto a MAV. This system will be centered on a micro turbine and self contained fuel source. The micro turbine will be attached to a rotor that is coupled to a generator. The design must also be contained in a housing that supports the turbine and necessary flow paths. 15 Microturbine III Senior Design 05002The generator of this system shall output a minimum of 5 Watts of power. To be useful in the application of MAV power production, the system must output at least 5Watts of power for onboard electrical equipment. In addition, if necessary, addition power produced could be used for propulsion. The micro turbine system shall weigh less than 45 grams. The prototype designed and built by the previous senior design team was within this weight limit, however did not include the fuel system and remained relatively large in size for MAV uses. To get closer to the goal of MAV application, the system must undergo weight and size reductions, along with design of the fuel system. This is why the design must undergo a drastic redesign of many components, time permitting. The micro turbine system includes the turbine, shaft, bearings, housing, seals, couple, fuel canisters, fuel delivery, choked flow nozzle and all hardware required for the housing to remain closed. It does not include the controls sensors, power converters, signal modifiers, and the generator.Currently the sizes of the components not included are due to the test set-up, our limited budget, and available resources within the team. For a practical application on MAVs, the generator must be incorporated as part of the turbine/housing. This would require tremendous research and is outside the scope of this project. The design should maintain ease of assembly and disassembly of the fuel/turbine/generator system. In thinking of eventual application, the system must be versatile and simple. Assembly and alignment should be quick and sure. Parts should also be easily replaceable in case of part malfunction. The Design Team should design the onboard fuel system. Last years design used an unlimited source of fuel for the turbine power. This year’s team shall design and produce a fuel system suited to fit our needs. 16 Microturbine III Senior Design 05002The generator selection should be optimized for our application. Previous generators were selected primarily because of size. This created a loss of efficiencies at certain power levels and operating speeds. The generator should be chosen to best fit all of our design parameters. 1.15 Organizational Chart05002 Micro-Turbine Project Leader – Cliff Cummings Mentor – Prof. Jeff KozakTurbine and Housing Fuel Systems PDR/CDR Lead – Joe Lead – Mark Allison CliffPaper Presentation Lead – Mark Lead - JoeFig 1-3: Organizational Chart2.0 Concept DevelopmentThis chapter will cover the different concepts the team investigated and redsigned.The first few sections discuss the break down of the team. Since there are several different aspects to the project, the team of four engineers broke up into subgroups.From the subgroups, ideas were generated and brought together to aid in concept development on housing, turbine, and fuel system designs.17 Microturbine III Senior Design 050022.1 SubgroupsWe found it necessary to split the design project into smaller subgroups headed up by individual members of the design team. The small group of four team members led to overlapping of members involved in each subgroup. The purpose of the subgroups is to investigate, research, and design concepts to be brought forth and implemented into the overall design. The subgroups created are Housing, Turbine, and Fuel System.2.1.1 Housing TeamThe housing subgroup’s main task was to reduce the size and weight of the turbine and flow housing. This subgroup was headed by Joe Calkins, with the assistance of Allison Studley. The main focus of their research was on scaling down the outer dimensions of the housing to be more appropriate for MAV applications. Further thought was placed on the bearing and seals to be used within the design and the flow path at both the inlet and outlet.2.1.2 Turbine TeamAllison Studley led the research into alternative turbine designs. With the support of Joe Calkins, the subgroup investigated numerous proven high efficiency turbine designs and their possible inclusion into our concept. The limited source of persons available prevented a full redesign of the turbine.2.1.3 Fuel System TeamThe fuel system required the primary initial attention as it had to be completely designed with no current benchmark. Heading up this subgroup was Mark Fazzio with18 Microturbine III Senior Design 05002 the assistance of Lincoln Cummings. The main focus of research and design was placed on the fuel canisters to be used. Additional attention was spent on the fuel delivery to the turbine including tubing, connectors, and nozzles.2.2 Housing ConceptsA major requirement of this year’s housing design is the implementation of the housing into the current MAV airframe. In order to meet this requirement, the new housing must be more compact than the previous design. After a session of housing concept brainstorming, it was determined that the circular design was the most compact, durable, and easily manufactured design. One improvement made upon last year’s design was the implementation of two separate inlet ports, which was able to eliminate the large inlet channel. The Fig 2-1: Housing Concept removal of this inlet channel allowed the diameter of the housing to be shrunk from1.875” to 1.25”. This allows for a much lighter, smaller housing design which is still capable of withstanding the high pressures of the system.2.2.1 BearingsThere are a few major design concerns when it comes to bearing selection in a design such as this. The high nominal rotational speed of 100,000 RPM requires a bearing which is rated for such high speeds. One design concern, which was experienced by previous teams, is the high pressures in the system. Previous teams had trouble with 19 Microturbine III Senior Design 05002 the high pressure blowing the grease out of the shielded bearings. From this, it was determined that sealed bearings were necessary. Other bearings were investigated, including air and magnetic bearings, but no bearings of a small enough size were found.2.3 Turbine ConceptsThe axial impulse and Francis turbines are impulse turbines that provide high efficiency. They are 3 dimensional designs and are very costly to produce. The axial impulse uses axial flow and the Francis uses a combination of radial and axial flow. The Pelton wheel is a design that developed in the 1870’s by Lester Pelton. It uses cups that are pushed by the moving fluid. It will hit the turbine in the center of two adjacent cups and the fluid will flow around the sides. The impulse causes the wheel to move. A 3-D Pelton wheel is highly efficient. A 2-D Pelton wheel uses a similar concept, however does not have the cup shape. They are concave blades that will Fig 2-2: 3-D Pelton Wheel Turbine turn the wheel around its axis. Its efficiency is nowhere near that of the 3-D but is much easier to produce.2.4 Fuel System ConceptsThe fuel system is the truly new component to the microturbine design. The task at hand is to move from the general source of fuel provided by external tanks to a fully integrated system. This system is to include the fuel itself, a canister, tubing, and flow regulation. These components are to be made a part of the overall system and be included into the airframe of the MAV. 20 Microturbine III Senior Design 05002Methods in which this could be done were contrived as a group. Stemming from the single inlet housing of the previous design would lead to the use of a single canister to hold the compressed gas. This method became obsolete as a single canister would not fit along the center of the MAV, and placing the canister to one side would cause severe imbalance of the MAV. The design would thus incorporate two canisters of fuel to be placed equally on either side of the fuselage and be ducted into a duel inlet housing design. Placement of the canisters then had two options. The first was to place the canisters along side the fuselage, while the second was to incorporate them along the leading edges of wings of the MAV.2.4.1 FuelThe options for the fuel to be used were kept to those which are most easily available. Brainstorming let to a choice between compressed air, Nitrogen, and CarbonDioxide. Due to weight being a key issue in the design parameters, Nitrogen was chosen as the optimal gas to be used to propelling the turbine. A second advantage for the use ofNitrogen is that it acts as an ideal gas under our conditions.The required amount of fuel needed to operate the generator for a time of three minutes would be determined in order to find the necessary quantity of Nitrogen to be stored. This calculation would be performed based on the properties of the Nitrogen, and characteristics of the flow. Once this quantity is known, a supplier of customized compressed gas canisters will be used for purchasing the fuel.21 Microturbine III Senior Design 050022.4.2 Tubing & ConnectorsTransporting the fuel from the canisters to the housing was the next step in the fuel system design. Tubing to duct the fuel would be used, and two options presented themselves. Tubing to be used could be made of plastic, such as surgical tubing, or metal, either aluminum or copper. The positive aspects of surgical tubing being lightweight and flexible led to this as the optimal choice. However, once the gas pressure to be used within the tubing was determined, it was concluded that metal tubing would have to be used to withstand the pressures.Once this choice had been made, thoughts turned to the connections at the canisters as well as at the housing. Several options were brainstormed including threaded fittings, epoxy, and compression fittings. As each of these were researched and analyzed, an alternative to the tubing/connector component presented itself. The eventual supplier of the compressed gas also provides puncturing devices to be used to pierce the canister and duct the gas out through a threaded hole. A male-to- male brass coupler could then be threaded into the puncture device and the housing.Thus no additional tubing or connectors are needed.2.4.3 Flow RegulationDue to the concept of a high pressure gas canister to be used for storage of the fuel onboard the MAV, the flow out of the regulator and into the housing must be regulated to an efficient and effective pressure. Since a redesign of the turbine would not be performed, the pressure values from last year’s data would be used to determine an inlet pressure to the turbine. 22 Microturbine III Senior Design 05002Based on this information, several concepts of regulation were brainstormed. The use of a spring regulator is commonplace for such flow regulation. The size and weight of this, however, would be too large for our needs. A bellows spring had potential as it is generally lighter and smaller than a standard spring regulator. While this appeared to be a feasible option, it was still larger than we would prefer.The final concept would be the simplest of the three. By choking the flow of the gas and thus achieving a flow speed of Mach 1, by fluid dynamics this would provide a constant mass flow. Once this method was determined, options presented themselves on how this could be done. An inline small diameter throat could be placed in the tubing between the canister and housing. This option would merely add components to the system as well as additional connections which serve as a greater number of leakage points. The other concept for choking the flow is to incorporate the narrow diameter throat with the nozzle within the housing. To achieve the required mass flow, a simple standard nozzle would be insufficient. The use of a micro-nozzle available from the RITMicroelectonic Engineering department would be optimal for the requirements. 2.5 GeneratorWithout any previous electrical engineering background, Dr. Kozak suggested to us to speak with Dr. Lyshevski of the electrical engineering department. We know we need a 3-phase motor that will generate a target speed of 100,000 RPM and 5W of power.The size needs to be a 1.5mm diameter shaft, about 1” total diameter, and obviously as light as possible. 23 Microturbine III Senior Design 05002In speaking with Dr. Lyshevski, he informed us that it needs to be a brushless dc motor and pointed us to two companies online that we may be able to find what we need.In researching these companies, it was found that the highest speed for this size motor is about 65,000 RPM. This may be able to be used, however we would like something faster. Last year’s electrical engineer, Ream Kidane, will try to be contacted in order to see where their motor was from. 3.0 FeasibilityTwo different assessment methods were used to decide on the actual designs for fabrication. The feasibility of all concepts centered on the overall objectives and goals of the project. The key aspects which were considered in the assessments were weight, size, cost, availability, and manufacturability. For concepts which involved only two options, a direct comparison was used, while a weighted Pugh’s comparison was used on components with more than two concepts. Feasibility assessments were performed on the housing, turbine, bearings, fuel system, tubing, and flow regulation. A brief discussion and procedure of the assessment are found in the following sections. Final decisions and selections will be discussed in the conclusion segment of this chapter.3.1 Turbine FeasibilityThe feasibility attributes considered in the turbine selection are cost and availability, cost being the more weighted of the two. Francis and axial impulse are very difficult to manufacture. To do this would cost a lot and take a long time. These designs are not practical for our application. 24 Microturbine III Senior Design 05002Of the Pelton wheel designs, the 3-dimensional is more costly due to the added machining, however may not be out of possibility. For time and cost considerations, the2-dimensional design was chosen. We will be using the same design from last year. This will obviously not add to efficiency but this was chosen as the best option so we could focus on other aspects. If there is time, we may have a 3-dimensional design option available for quoting.3.2 Housing FeasibilityThrough our process of housing concept development, we determined that the most appropriate concept was similar to last year’s design. The new design would have 2 inlets and 2 outlets, as opposed to last year’s 1 inlet 2 outlet design. The feasibility of this concept is shown below as compared to last year’s design. Through this feasibility test, it was determined that the new concept is more feasible than last year’s design and will be used as the baseline for further design.25 Microturbine III Senior Design 05002Housing Feasibility y t i l i b a r y l u t g i t a l t n i c i o t t a b f T s h h a l l u t i g g a i i e n s w a t z e e a o v o i o C S W A M R T W Cost \ | \ | 1 1 0.1 Size \ - \ 2 2.5 0.25 Weight - \ 1.5 3 0.3 Availability | 0 0.5 0.05 Manufacturability 0 3 0.3Column Total 0 0.5 1.5 0.5 3 t p e c n n o g i C s t e e l D t u s ' g r O n a i 2 t e t h Y e g t l i s n e I aW L 2 Cost 0.1 3 2 Size 0.25 3 2 Weight 0.3 3 3 Availability 0.05 3 3 Manufacturability 0.3 3 2Weighted Average 3.00 2.35 Normalized Average 1.00 0.78 Table 3.1: Housing Feasibility 3.3 Bearing FeasibilityThrough our research of available bearings, our findings were very similar to last year’s bearings. There are no air or magnetic bearings small enough for our application.This causes them to be unfeasible. This leaves the axial and radial bearings. Due to the low loads and thrust on the bearings, the radial bearings are the most feasible bearings for our application. They are of lower cost, similar RPM rating and availability to the axial thrust bearings.26 Microturbine III Senior Design 05002Bearing Feasibility g y l t n g i i a l t t n i i a o t t b R T s h h a l l t i g g a i i e M s w a t z e e o v P o i o C S W A R R T W Cost - - | | 2 2 0.2 Size - | | 1 1 0.1 Weight | | 0 0 0 Availability \ 0.5 3.5 0.35 RPM Rating 0 3.5 0.35Column Total 0 0 0 3 3.5 s g n s i r s g a g n i s e n r i g B a r g n e a i c n i r e i B t t a l B e h e a l n i g B a i g i d r e a i x a W TableA 3.2: BearingM FeasibilityA R Cost 0.2 4 4 3 2 Size 0.1 5 5 2 2 Weight 0 3 3 3 3 Availability 0.35 5 5 2 2 RPM Rating 0.35 2 2 3 3Weighted Average 3.40 3.40 2.70 2.60 Normalized Average 1.13 1.13 0.90 0.873.4 Fuel System FeasibilityThe fuel system is composed to three components, the fuel canister, tubing, and flow regulator. Each of these were assessed from a feasibility standpoint separately, as outlined below. Since each is a direct comparison, a Pugh’s comparison was not needed.The critical features of each were the weight, size, and availability of the components. As a collective group, determining the layout of the fuel system itself provided several concepts. The three main concepts were: Single fuel tank with a split flow duct27 Microturbine III Senior Design 05002 Duel fuel tanks positioned within the leading edge of the MAV Duel fuel tanks positioned along the fuselage of the MAVIt was quickly decided that a single fuel tank would be a poor option as it could not be centered properly on the MAV, thus disrupting the stability and control of the aircraft. The positioning of the duel fuel tanks was not of real concern until the size of the tanks was known. Once we calculated the amount of nitrogen required and pressure in which it must be stored, it became infeasible to place the canisters within the leading edge. This decision was supported by the design of the MAV in which the leading edge is not straight off of the fuselage. The final decision was made to align the fuel canisters along side of the turbine and generator within the fuselage.3.4.1 Fuel FeasibilityThe nature of the project kept the fuel options to a minimum. The use of a compressed gas to be used to drive a turbine was already known; therefore the selection of gases to be used was left. Due to availability, cost, and environmental issues, the list was quickly condensed down to compressed air, nitrogen, and carbon dioxide. The weight became the separating characteristic of the choices. Nitrogen was chosen due to its very low density, and high compressibility. In addition to these properties, the flow characteristics proved to be favorable as nitrogen would act as an ideal gas within our system.3.4.2 Tubing FeasibilityThe next step in the fuel system is the delivery from the fuel canisters to the housing. To do this, two choices presented themselves, plastic or metal tubing. The28 Microturbine III Senior Design 05002 plastic tubing would likely be surgical tubing which is easily available. Aluminum or copper would be used in the instances of metal tubing. Due to the high pressures the tubing would be experiencing, surgical tubing was determined to be infeasible as a result of connection issues. The choice was made for use of metal tubing and connectors. However, as the design began to come together it was realized that a male-to-male threaded elbow coupler would reduce the number of connections and act as the tubing directly from the puncture device to the housing.3.4.3 Flow Regulation FeasibilitySince the fuel will be stored at a high pressure, the mass flow must be regulated.In order to do this, and maintain a light weight compact design, two concepts were made.The first was the use of a spring operated regulator, likely using a bellows spring. The bellows regulator would require additional connections to tubing as well as using more space in the fuselage. The second is to choke the flow using a mirco-nozzle, thus providing a constant mass flow. The micro-nozzle was chosen on the basis that it is lighter in weight, smaller, and can be an added piece to the housing.4.0 Objectives and Specifications4.1 ObjectivesThe objectives of the Microturbine Generator Senior Design project were presented prior to work being performed. The objectives were laid out by the RITMechanical Engineering department in collaboration with MAV project teams and goals.The key objectives are listed as follows. Design a micro-turbine system 29 Microturbine III Senior Design 05002 Build the micro-turbine system Produce 5 watts of power Overall system weight less than 45 grams Integrate into a MAV airframe Complete project by May 2005 Drive the propeller4.2 Performance SpecificationsThe objectives we are set out to achieve are established based on previous work performed, and the goal of producing a lighter and battery power alternative. During this design process, we are likely to encounter a number of issues which may not have been foreseen. While every attempt to work through these obstacles will be made, limiting factors due to time and budget will inhibit us to do so. By understanding the performance specifications, the team will be guided toward the appropriate tasks intended to be achieved by the conclusion of the project. With this thorough understanding of the performance specifications, the team will be able to justify those issues that must be dealt with and those which can be left for future design teams. The key objective of the project is to scale down the current micro turbine generator design as well as include the fuel system into the design. The specifications established were to produce 5 watts of continuous power, size the system to fit within theMAV, and keep the weight of the system less than 45 grams. Since the turbine has been proven to produce sufficient power, heavy consideration this year was on the size and weight of the overall system. 30 Microturbine III Senior Design 050024.3 Design PracticesTo help the team achieve the objectives and specifications that was established, a list of design practices were kept in mind when team members were developing designs.A list of these practices is as follows:1) Design for Manufacturability – One achievement in the new design of the housing is a more simplified flow path. This design has basic geometric shapes which can be easily manufactured at RIT. This improvement will save both money and time in manufacturing as opposed to seeking an outside vendor.2) Design for Assembly – The initial design is intended to be assembled and disassembled with ease. This allows for streamlined testing as little time will be required between tests for maintenance. In addition, should certain aspects of the design require modification; any piece can be removed and interchanged with simplicity.4.4 Safety IssuesTo ensure the safety of all members on the team, a set of safety precautions were established. Since the testing of the design will undergo high pressures and components will be spinning at high speeds, it is imperative that the members of the team follow these guidelines.1) To avoid any flying objects from hurting the engineers and whoever may come in contact with it, all testing will be conducted in a contained area. The container will be made out of plexiglass. The plexiglass is transparent so the engineers can see the process, and it is strong enough to compensate for any accidents involving the design.31 Microturbine III Senior Design 050022) Engineers must wear goggles while testing. Despite the fact that there is a layer of plexiglass between the engineer and the micro turbine, there is always room for the unexpected. By wearing goggles, this will preserve the well being of the engineer.3) If team members are to machine any parts in the machine shop, the machine shop safety guidelines must be followed strictly.4) The team ought to be careful when working with the electronics. There is a chance of minor electrical shocks caused by the generation of electrical power by the turbine.5) Due to the high speed the components of the turbine will be spinning at, there may be a slight raise in temperature. When handling the turbine after testing, team members must be careful and make sure all parts are at handling temperature.5.0 Design Analysis & Synthesis5.1 Turbine Analysis & SynthesisInitial research into turbine designs led the team to use last year’s turbine design.This was done because of two major factors, first the amount of resources and time that would be required to design a new turbine, as well as the lack of technological advancements in the last year. The 5/16 in turbine design was chosen because of the previous RIT micro-turbine teams. The first design was 1/2 an inch and produced 18 W, the second design was a 1/4 of an inch and produced 0.6 W. Much of the power loss was attributed to housing design problems, which lead last year’s team to develop a turbine within that size range. Last year’s turbine produced 19 W. 32 Microturbine III Senior Design 05002The tip speed of the turbine blades was calculated to be optimal at approximately400,000 rpm, this is much larger than the generator and more importantly the bearing can handle. The maximum practical velocity for the turbine is about 100,000 rpm. Research into the blade size, based on Flockhart’s paper “Experimental and Simulation Analysis ofMicroturbines” states that the smaller the blade thickness the greater the torque performance. The length and number of blades also follow Flockhart’s logic. The pitch diameter of the blade should be as large as possible so that the pitch diameter is in the middle of the blade. The number of blades should be maximized to the point that the jet is not being impinging by the next blade. If the next blade impinges the current blade then it would greatly decrease the turbine efficiency. The major limiting factors on turbine design are the machining cost and lead time.Three dimensional turbine designs are more efficient but cost much more. The pelton type turbine is one of these three dimensional turbine designs; it has a ridge that follows the edge of the blade radially. The pelton type turbine would cost well over our entire budget. Our budget and practicality of having an easily machined and replaceable turbine greatly limits the turbine designs that can be considered. Last year’s team designed their own turbine using two set parameters, 100,000 rpm and5/16 in outer diameter. These parameters lead the team to design 0.052 in high blades with a pitch diameter of 0.27 in. Using equation 5-1 they calculated that there should be8 blades: n  (r  d / 2) 2 (Equation 5-1) 1 R 233 Microturbine III Senior Design 05002 n is the number of blades; r is the pitch radius; d is the jet diameter; and R is the overall turbine radius. A range of 0.01 and 0.03 inches was used for the jet diameter. The blade thickness was set at 5 degrees and the tip angle was determined to be 39 degrees. To decrease the chance of the back of the blade hitting the jet flow a low profile design was used. The final turbine design is shown below in figure XXXX.Fig 5-1: Blade Fig 5-2: Turbine DesignThe previous team used Engineering Fluid Mechanics to validate the design. The mass flow rates were calculated using the following equation:T  rQ(1 cos( ))(v jet  r) (Equation 5-2)Where T is torque; r is pitch diameter; ρ is working fluid density β a correction factor; Q is volumetric flow rate; vjet is the velocity of the jet; and Ω is the turbine’s rotational velocity. The efficiency of the turbine was also calculated using another equation:P r r   2  2 (1 )(1 cos( )) (Equation 5-3) 0.5Qv jet v jet v jetWhere the efficiency is equal to the power output divided by the incoming kinetic energy.This equation, however, is limited as the efficiency is also dependant on the other components of the micro-turbine system.34 Microturbine III Senior Design 050025.2 Housing Analysis & SynthesisThrough the feasibility assessment, a similar design to last year’s microturbine housing was developed. The major difference in this year’s design is the implementation of two individual inlets to the turbine passage. This allows the previously designed flow channel to be eliminated from the design. The elimination of this flow channel allows for less complex geometry for ease of machining, as well as smaller diameter housing for a more compact and lighter weight design. Very similar to last year’s design, this year’s housing is focused around the turbine passage. The bearings in the housing, as well as the housing cap, will help to align the turbine concentrically in the housing. Since last year’s turbine design is being implemented into this year’s design, the turbine passage will be the same dimensions as last year with a diameter of 0.333” and a depth of 0.115”. In order to cut down on the head losses in the housing, the inlet and outlet ducts are straight through. This will eliminate the losses which occurred in last year’s design with the 90 degree outlet channel. Pressure losses from the cap will be contained by an o-ring that is fitted into the housing cap. The cap will be held into place with two bolts, which will also align the generator and it’s bracket on the opposite side of the housing.Since the housing cap concentric with the housing, it is self aligning and will provide for a more precise alignment of the turbine and it’s shaft.5.2.1 Housing FEAAnalysisThrough the use ofFinite Element Analysis of 35Fig 5-3: Cap FEA Microturbine III Senior Design 05002 the housing, it was determined that the 30% fiberglass reinforced Nylon 6/6 would withstand the high pressures under our current design. The Nylon 6/6 30% FiberglassReinforced has a tensile strength of 23,206 psi, along with a density of 1.38 g/cm^3. The target pressure inside of the housing for our design is 100psi, however a safety factor of3.0 was added for this case since there are such high pressures as well as human interaction during testing. With this in mind, the housing was tested at 300psi, assuming that there is not leakage past the o-ring seal. The above analysis showed the maximum stress in the housing under a 300psi load to be 780psi. Fig 5-4: Housing FEAAfter completion of this analysis it was determined that the smaller design would withstand the high pressures with the use of lightweight Nylon 6/6. Due to its light weight and ease of machining, and inexpensive price, Nylon 6/6 was determined to be the best choice of material for the housing. Alternative materials were then researched for36 Microturbine III Senior Design 05002 the housing. A lighter weight alternative is Nylon 6/6 with 10% Carbon Fiber Reinforced providing 18,855 psi of tensile strength and a density of 1.18 g/cm^3.5.2.2 Shaft Selection & AnalysisAt the current time, we are in the process of locating a generator to integrate into our design. Since a generator has not yet been found, our shaft selection cannot be determined at this time. The current design is based around the 1.5 mm shaft that was used on the previous design. Minor changes to the design may be made for a different size shaft, since the shaft size will be determined by the generator shaft size. The shaft will be of the same diameter as that of the generator, for ease of coupling the two shafts together.5.2.3 Bearing SelectionAfter researching all of the different options for bearings, it was determined that radial sealed bearings were the best fit for this application. The seals are necessary due to the high pressures, as previous teams had problems with shielded bearings losing their lubrication. The final bearing selection will be determined by the shaft size once a generator is found. At the current time, the bearing selection has been based upon the previous shaft size of 1.5 mm.The other major issue for bearing selection was the high rotational speeds of the system. The bearings for this system must be rated for a minimum of 100,000RPM. It was found that sealed bearings of 1.5 mm ID were attainable at a relatively inexpensive price. The final bearing selection will be determined upon the selection of a generator and shaft size.37 Microturbine III Senior Design 050025.2.4 Coupling SelectionOne of the major issues experienced by the previous microturbine design was the selection of a coupling to connect the turbine shaft to the generator shaft. Through much research, it was determined that their best selection for a coupling was a small piece of shrink tubing. The main reason for this was the fact that all of the micro couplings researched were not rated for the high rotational speeds or did not have the necessary rigidity. A bit of research was done this year to search for any new technologies which may allow for a more rigid and high speed coupling, however no couplings were found.This leads us back to the previous team’s use of the shrink tubing as a coupling between the two shafts. It was estimated previously that there is approximately 1% loss in the shrink tubing coupling.5.3 Fuel System Selection & AnalysisThe fuel system became the critical aspect of this years Microturbine SeniorDesign project. The fuel system in the past used laboratory gas cylinders in conjunction with flow regulation equipment. This laboratory setup was used to as a result of the previous generation’s goals: design a turbine and housing to be placed on a MAV, without consideration of the fuel system. The goal this year is to include the fuel system into the MAV, thus requiring it to be lightweight and miniature.5.3.1 Fuel SelectionThe fuel to be used for the microturbine had to meet three main criteria to be selected. Those criteria were its weight, its flow properties, and the availability of the38 Microturbine III Senior Design 05002 gas. As a result of these conditions, and based on the feasibility assessment of the gases,Nitrogen was chosen as the optimal gas to be used. Nitrogen has a lower molecular weight than either compressed air or carbon dioxide. Under our storage and flow conditions, the nitrogen acts as an ideal gas, thus simplifying the flow regulation.Finally, nitrogen is a widely used and easily available gas.5.3.2 Tubing & Connectors SelectionAs the housing and fuel canisters were designed and selected, the tubing and connections remained a secondary thought to be determined once other aspects of the design were known. Throughout the process, the general concept to be used was a connection at the fuel canister, tubing, and another connection at the housing.Consideration into the puncture of the fuel canister presented additional connections that would be required. As the method of puncture was determined, which would be a supplied puncture device available from the fuel supplier, the tubing and connection issue took a turn. It was decided that the number of connections and size of the system could be reduced by use of a straight male-to-male threaded coupler connecting the puncture device directly to the housing. 5.3.3 Flow RegulationFlow regulation was a fairly simple component of the system to select. Due to the primary requirements of light weight and small size, a simple choked flow would be optimal for our design. A micro-nozzle fabricated in the RIT Microelectronics laboratory is the desired method for regulating the mass flow of the nitrogen. The micro-nozzles are fabricated out of a silicone wafer through simple means and require minimal 39 Microturbine III Senior Design 05002 manufacturing time. Due to the molecular structures of the silicone, a tapered jet nozzle is formed. This is a desired feature as it increases the efficiency of the nozzle.5.3.4 Fuel System AnalysisThe most critical piece to the fuel system to be determined was the quantity of gas required. The first step in analyzing this is to determine the type of flow which the system will be experiencing. Based on criteria from thermodynamics, an ideal gas is assumed when operating temperature is greater than twice the critical temperature, and operating pressure is less than five times the critical pressure of the gas. Based on thermodynamic properties of nitrogen, our system is within this criterion, therefore allowing for ideal gas flow calculations.The quantity of fuel required is dependent on the desired runtime of the system.The goal of the design is for a runtime of three minutes. The use of the choked flow nozzle results in a constant exit velocity of Mach 1 of the fuel along with a constant exit area. Determination of the density of fuel within the canister is derived byM   (Equation 5-4) o V where o is the density, M is mass, and V is volume.Based on the chemical characteristics of the chosen gas, nitrogen, and the assumption of constant room temperature exit flow, the exit velocity is calculated by  Vexit  M RT (Equation 5-5)   where Vexit is the exit velocity, M is the mach number, is the specific gas ratio, R is the ideal gas constant, and T is the temperature.Based on the equation of mass flow,40 Microturbine III Senior Design 05002  (Equation 5-6) m   * Aexit * exit the variable we are left with is the density of the nitrogen in the flow. Determination of the exit area of the nozzle to be 100 micrometers resulted in a mass flow rate of 1.53x10 -4 lbs/sec. In a choked flow system, this mass flow will remain constant, thus through simple calculation an initial required mass for the three minute runtime is determined.Based on this information, an initial mass of 13.6 grams of nitrogen in each of the two fuel canisters is required. 41 Microturbine III Senior Design 050026.0 Future Plans6.1 Test SetupTo save the nitrogen in the fuel canisters, the turbine and housing will be tested first with large tanks of laboratory nitrogen. After the design concept is proven, we will test our fuel canister system. In order to test the system to find the desired outputs, the previously designed test setup will be used. This system uses pressure sensors, a flow meter, and thermocouples, as well as current and voltage sensors to aquire the data through LabView. The open loop control system reads the incoming pressure then is regulated by a servo valve located on the inlet air pipe to the stagnation plenum. The system is able to read the inlet temperature T, pressure P, and volumetric flow rate V to calculate mass flow rate, as well as current and voltage to find power and efficiency. The pressure sensor is rated to 200 psi and the turbine should operate at 100 psi.The flow meter has a range of 10 L/min – 120 L/min, and the airflow is expected to be between 40 L/min – 90 L/min. The analog data of the sensors will be converted to digital for Labview to be able to compute everything. The Labview setup allows us to see the power output graphically as it runs and see the best conditions for the micro turbine to run.42 Microturbine III Senior Design 050026.2 ScheduleThe attached Gantt chart displays the proposed schedule for the design development of our project. Key events are shown to give the team goals for timely completion of project components as well as the overall project. The start and completion dates are listed by each component; the vertical arrows indicate task dependencies. Fig 6-1: Schedule43 Microturbine III Senior Design 050026.3 BudgetThe micro-turbine project team has a $1000 budget via a RIT grant that is intended to cover all expenditures associated with the project. The team plans on spending $676.83 of that budget for parts and machining. 05002 Micro-Turbine III ProjectComponent Description Price per Qty Line Price Housing Turbine $96.00 1 2 $192.00 Nylon rod $5.97 foot 1 $5.97 machining $10.00 1 1 $10.00 fittings $1.00 1 4 $4.00 bearings $40.00 10 10 $40.00 coupling $14.09 10 10 $14.09 Mini Stainless Steel Shaft $3.93 1 1 $3.93 O-Ring $4.00 100 100 $4.00 Nylon cheese head screw $5.60 100 100 $5.60 black nylon 6/6 nut $10.00 100 10 $1.00 Fuel Systems Ni Canisters $20.00 1 2 $40.00 Connector $0.62 1 2 $1.24 O-Ring $7.50 1 2 $15.00 Puncture components $20.00 1 2 $40.00 Jets $100.00 50 50 $100.00 Electrical Generator $200.00 1 1 $200.00Overall Cost $676.83 Fig 6-2: Budget44 Microturbine III Senior Design 050027.0 Conclusions The Micro Turbine Generator III team has successfully completed the first six aspect of the design process. These six facets includes: Recognize and Quantify Needs,Concept Development, Feasibility Assessment, Design Objectives and PerformanceSpecifications, Synthesis and Analysis, and finally Preliminary Design Documents.The eventual goal of the micro turbine is to provide Micro Air Vehicles with a dependable and reliable power source that is also light in weight. By utilizing compressed gases, the micro turbine will drive a generator, thus providing the electrical power to onboard equipment. The micro turbine must withstand 100,000 rpm and be capable of remaining intact and functioning at a pressure of 100 psi. The design must maintain the integrity of all the components especially the generator. The generator shall be reusable. The main task of this project has been achieved. That task was to design a fuel system to be incorporated with the turbine system, as well as scale the overall concept down to be implemented onto an MAV. The design includes a duel high pressure nitrogen fuel canister system ducted directly into the housing and regulated by a micro nozzle prior to turbine impulse. The housing was fully redesigned to be smaller and have a lighter weight than the previous design. Ease of manufacture has been considered in the overall design as well as use of easily acquired components. A finite element analysis performed on the housing and cap proved the design is sufficient to withstand the high pressure it will experience. At this point, the design is ready to move onto the parts acquisition, manufacturing, and testing stages. These aspects of the development will occur in the following quarter. 45 Microturbine III Senior Design 05002ReferencesAnderson, John D., Jr. Fundamentals of Aerodynamics. 3rd ed. New York: McGraw-Hill Companies, Inc. 2001Callister, William D. Jr. Introduction to Materials Science and Engineering, 4 th Edition. New York: John Wiley & Sons, 2000Desai, V. R. and N. M. Aziz. “Parametric Evaluation of Cross-Flow Turbine Performance.” Journal of Energy Engineering, Vol. 120, No. 1, April 1994. 17 – 34.Doty, F.D., B.L. Miller, and G.S. Hosford. “High Efficiency Microturbine Technology.” 26th Intersociety Energy Conversion Engineering Conference. Boston. August 1991.Fox, Robert W. and Alan T. McDonald. Introduction to Fluid Mechanics. 5th ed. New York: John Wiley & Sons, Inc., 1998.Hibbeler, R.C. Mechanics of Materials, 4 th Edition. New Jersey: Prentice Hall, 2000Holt, Dan. et. al. “Design of a Miniature Turbine for Power Generation on Micro Air Vehicles.” Kate Gleason College of Engineering Multi-Disciplinary Engineering Design Conference. Rochester, New York, May 2003Kang, Sangkyun, Jurgen Stampfl, Alexander G. Cooper, Fritz B. Prinz. “Application of the Mold SDM Process to the Fabrication of Ceramic Parts for a Micro Gas Turbine Engine.” Ceramic Materials and Components for Engineers. Germany. June 2000.Lin, Simien. Et.al. Micro Turbine Senior Design Team: Preliminary Design Report. RIT, 2004.Mehra, A., S. A. Jacobson, and C.S. Tan. “Aerodynamic Design Considerations for the Turbomachinery of a Micro Gas Turbine Engine.” 25th National and 1st International Conferency on Fluid Mechanics and Power, ASME. New Dehli. June 2003.46 Microturbine III Senior Design 05002AppendixA. Appendix A – Turbine Performance Graphs (Based on 04013 Design)47 Microturbine III Senior Design 0500248 Microturbine III Senior Design 0500249 Microturbine III Senior Design 05002B. Appendix B – Turbine Performance Data (Based on 04013 Design)Max Power Output (nozzle .115 X .02).Power  Pjet  2  2 mrpitchu jet  rpitch1 cos( ) Pitch Radius rpitch = 0.13 in 0.0033 m Turbine Vel. Omega = 100000 rpm 10472 rad/s Beta = 84.5 deg 1.475 radStagnation Pressure P kPa psig (abs) kPa (abs) 20 239 126 25 274 145 30 308 163 Temperature M=1 35 343 181 °C u (m/s) 40 377 199 10 337 45 412 217 15 340 50 446 236 20 343 55 481 254 25 346 60 515 272 65 550 290 70 584 308 75 618 327 80 653 345 85 687 363 90 722 381 R= 287 95 756 400 A= .115*.02*2 0.0046 in2 100 791 418 3.01E-06 m2 105 825 436 110 860 454 115 894 472 120 929 491T= 10°C T= 15°C 50 Microturbine III Senior Design 05002 mdot Power P mdot Power P (psig)  (kg/m3) (kg/s) (W) (psig)  (kg/m3) (kg/s) (W) 20 1.56 1.58E-03 15 20 1.53 1.56E-03 15 25 1.78 1.81E-03 17 25 1.75 1.79E-03 17 30 2.00 2.03E-03 19 30 1.97 2.02E-03 19 35 2.23 2.26E-03 21 35 2.19 2.24E-03 21 40 2.45 2.49E-03 24 40 2.41 2.47E-03 24 45 2.68 2.72E-03 26 45 2.63 2.69E-03 26 50 2.90 2.94E-03 28 50 2.85 2.92E-03 28 55 3.13 3.17E-03 30 55 3.07 3.14E-03 30 60 3.35 3.40E-03 32 60 3.29 3.37E-03 32 65 3.57 3.63E-03 34 65 3.51 3.59E-03 34 70 3.80 3.85E-03 36 70 3.73 3.82E-03 36 75 4.02 4.08E-03 39 75 3.95 4.05E-03 39 80 4.25 4.31E-03 41 80 4.17 4.27E-03 41 85 4.47 4.54E-03 43 85 4.39 4.50E-03 43 90 4.70 4.76E-03 45 90 4.61 4.72E-03 45 95 4.92 4.99E-03 47 95 4.83 4.95E-03 47 100 5.14 5.22E-03 49 100 5.05 5.17E-03 49 105 5.37 5.45E-03 52 105 5.27 5.40E-03 52 110 5.59 5.67E-03 54 110 5.49 5.62E-03 54 115 5.82 5.90E-03 56 115 5.72 5.85E-03 56 120 6.04 6.13E-03 58 120 5.94 6.07E-03 58T= 20°C T= 25°C mdot Power P mdot Power P (psig)  (kg/m3) (kg/s) (W) (psig)  (kg/m3) (kg/s) (W) 20 1.50 1.55E-03 15 20 1.48 1.54E-03 15 25 1.72 1.77E-03 17 25 1.69 1.76E-03 17 30 1.94 2.00E-03 19 30 1.90 1.98E-03 19 35 2.15 2.22E-03 21 35 2.12 2.20E-03 21 40 2.37 2.45E-03 24 40 2.33 2.42E-03 24 45 2.59 2.67E-03 26 45 2.54 2.65E-03 26 50 2.80 2.89E-03 28 50 2.76 2.87E-03 28 55 3.02 3.12E-03 30 55 2.97 3.09E-03 30 60 3.24 3.34E-03 32 60 3.18 3.31E-03 32 65 3.45 3.56E-03 34 65 3.39 3.53E-03 34 70 3.67 3.79E-03 37 70 3.61 3.75E-03 37 75 3.89 4.01E-03 39 75 3.82 3.98E-03 39 80 4.10 4.23E-03 41 80 4.03 4.20E-03 41 85 4.32 4.46E-03 43 85 4.25 4.42E-03 43 90 4.53 4.68E-03 45 90 4.46 4.64E-03 45 95 4.75 4.90E-03 47 95 4.67 4.86E-03 47 100 4.97 5.13E-03 49 100 4.88 5.08E-03 50 105 5.18 5.35E-03 52 105 5.10 5.31E-03 52 110 5.40 5.58E-03 54 110 5.31 5.53E-03 54 115 5.62 5.80E-03 56 115 5.52 5.75E-03 56 120 5.83 6.02E-03 58 120 5.74 5.97E-03 5851 Microturbine III Senior Design 05002Max Power Output (nozzle .115 X .02) v. OmegaT=20 deg C=20,000 rpm =40,000 rpm  mdot Power P  mdot Power P (psig) (kg/m3) (kg/s) (W) (psig) (kg/m3) (kg/s) (W) 20 1.50 1.55E-03 3 20 1.50 1.55E-03 6 25 1.72 1.77E-03 4 25 1.72 1.77E-03 7 30 1.94 2.00E-03 4 30 1.94 2.00E-03 8 35 2.15 2.22E-03 5 35 2.15 2.22E-03 9 40 2.37 2.45E-03 5 40 2.37 2.45E-03 10 45 2.59 2.67E-03 6 45 2.59 2.67E-03 11 50 2.80 2.89E-03 6 50 2.80 2.89E-03 12 55 3.02 3.12E-03 7 55 3.02 3.12E-03 13 60 3.24 3.34E-03 7 60 3.24 3.34E-03 14 65 3.45 3.56E-03 7 65 3.45 3.56E-03 15 70 3.67 3.79E-03 8 70 3.67 3.79E-03 16 75 3.89 4.01E-03 8 75 3.89 4.01E-03 17 80 4.10 4.23E-03 9 80 4.10 4.23E-03 17 85 4.32 4.46E-03 9 85 4.32 4.46E-03 18 90 4.53 4.68E-03 10 90 4.53 4.68E-03 19 95 4.75 4.90E-03 10 95 4.75 4.90E-03 20 100 4.97 5.13E-03 11 100 4.97 5.13E-03 21 105 5.18 5.35E-03 11 105 5.18 5.35E-03 22 110 5.40 5.58E-03 12 110 5.40 5.58E-03 23 115 5.62 5.80E-03 12 115 5.62 5.80E-03 24 120 5.83 6.02E-03 13 120 5.83 6.02E-03 25=60,000 rpm =80,000 rpm52 Microturbine III Senior Design 05002 mdot Power P  mdot Power P (psig) (kg/m3) (kg/s) (W) (psig) (kg/m3) (kg/s) (W) 20 1.50 1.55E-03 9 20 1.50 1.55E-03 12 25 1.72 1.77E-03 11 25 1.72 1.77E-03 14 30 1.94 2.00E-03 12 30 1.94 2.00E-03 16 35 2.15 2.22E-03 13 35 2.15 2.22E-03 18 40 2.37 2.45E-03 15 40 2.37 2.45E-03 19 45 2.59 2.67E-03 16 45 2.59 2.67E-03 21 50 2.80 2.89E-03 17 50 2.80 2.89E-03 23 55 3.02 3.12E-03 19 55 3.02 3.12E-03 25 60 3.24 3.34E-03 20 60 3.24 3.34E-03 26 65 3.45 3.56E-03 22 65 3.45 3.56E-03 28 70 3.67 3.79E-03 23 70 3.67 3.79E-03 30 75 3.89 4.01E-03 24 75 3.89 4.01E-03 32 80 4.10 4.23E-03 26 80 4.10 4.23E-03 33 85 4.32 4.46E-03 27 85 4.32 4.46E-03 35 90 4.53 4.68E-03 28 90 4.53 4.68E-03 37 95 4.75 4.90E-03 30 95 4.75 4.90E-03 39 100 4.97 5.13E-03 31 100 4.97 5.13E-03 40 105 5.18 5.35E-03 32 105 5.18 5.35E-03 42 110 5.40 5.58E-03 34 110 5.40 5.58E-03 44 115 5.62 5.80E-03 35 115 5.62 5.80E-03 46 120 5.83 6.02E-03 36 120 5.83 6.02E-03 48=100,000 rpm =120,000 rpm  mdot Power P  mdot Power P (psig) (kg/m3) (kg/s) (W) (psig) (kg/m3) (kg/s) (W) 20 1.50 1.55E-03 15 20 1.50 1.55E-03 18 25 1.72 1.77E-03 17 25 1.72 1.77E-03 20 30 1.94 2.00E-03 19 30 1.94 2.00E-03 23 35 2.15 2.22E-03 21 35 2.15 2.22E-03 25 40 2.37 2.45E-03 24 40 2.37 2.45E-03 28 45 2.59 2.67E-03 26 45 2.59 2.67E-03 30 50 2.80 2.89E-03 28 50 2.80 2.89E-03 33 55 3.02 3.12E-03 30 55 3.02 3.12E-03 35 60 3.24 3.34E-03 32 60 3.24 3.34E-03 38 65 3.45 3.56E-03 34 65 3.45 3.56E-03 40 70 3.67 3.79E-03 37 70 3.67 3.79E-03 43 75 3.89 4.01E-03 39 75 3.89 4.01E-03 45 80 4.10 4.23E-03 41 80 4.10 4.23E-03 48 85 4.32 4.46E-03 43 85 4.32 4.46E-03 50 90 4.53 4.68E-03 45 90 4.53 4.68E-03 53 95 4.75 4.90E-03 47 95 4.75 4.90E-03 55 100 4.97 5.13E-03 49 100 4.97 5.13E-03 58 105 5.18 5.35E-03 52 105 5.18 5.35E-03 61 110 5.40 5.58E-03 54 110 5.40 5.58E-03 63 115 5.62 5.80E-03 56 115 5.62 5.80E-03 66 120 5.83 6.02E-03 58 120 5.83 6.02E-03 68=140,000 rpm  mdot Power P (psig) (kg/m3) (kg/s) (W)53 Microturbine III Senior Design 0500220 1.50 1.55E-03 20 25 1.72 1.77E-03 23 30 1.94 2.00E-03 26 35 2.15 2.22E-03 29 40 2.37 2.45E-03 32 45 2.59 2.67E-03 34 50 2.80 2.89E-03 37 55 3.02 3.12E-03 40 60 3.24 3.34E-03 43 65 3.45 3.56E-03 46 70 3.67 3.79E-03 49 75 3.89 4.01E-03 52 80 4.10 4.23E-03 55 85 4.32 4.46E-03 57 90 4.53 4.68E-03 60 95 4.75 4.90E-03 63 100 4.97 5.13E-03 66 105 5.18 5.35E-03 69 110 5.40 5.58E-03 72 115 5.62 5.80E-03 75 120 5.83 6.02E-03 78Max Power Output Efficiency v. T=20 deg C v. 54 Microturbine III Senior Design 05002P (psig)  (kg/m3) mdot (kg/s) Power (W)   20 1.50 1.55E-03 3 3.57 20,000 20 1.50 1.55E-03 4 4.44 25,000 20 1.50 1.55E-03 5 5.30 30,000 20 1.50 1.55E-03 6 6.15 35,000 20 1.50 1.55E-03 6 7.00 40,000 20 1.50 1.55E-03 7 7.83 45,000 20 1.50 1.55E-03 8 8.65 50,000 20 1.50 1.55E-03 9 9.47 55,000 20 1.50 1.55E-03 9 10.27 60,000 20 1.50 1.55E-03 10 11.07 65,000 20 1.50 1.55E-03 11 11.86 70,000 20 1.50 1.55E-03 12 12.63 75,000 20 1.50 1.55E-03 12 13.40 80,000 20 1.50 1.55E-03 13 14.16 85,000 20 1.50 1.55E-03 14 14.91 90,000 20 1.50 1.55E-03 14 15.66 95,000 20 1.50 1.55E-03 15 16.39 100,000 20 1.50 1.55E-03 16 17.11 105,000 20 1.50 1.55E-03 16 17.82 110,000 20 1.50 1.55E-03 17 18.53 115,000 20 1.50 1.55E-03 18 19.22 120,000 20 1.50 1.55E-03 18 19.91 125,000 20 1.50 1.55E-03 19 20.59 130,000 20 1.50 1.55E-03 19 21.26 135,000 20 1.50 1.55E-03 20 21.91 140,00055 Microturbine III Senior Design 05002Efficiency v. Pressure (5 W Output)T=20 deg C=20,000 rpm P (psig)  (kg/m3) mdot (kg/s)  20 1.50 1.55E-03 5.48 25 1.72 1.77E-03 4.79 30 1.94 2.00E-03 4.25 35 2.15 2.22E-03 3.82 40 2.37 2.45E-03 3.47 45 2.59 2.67E-03 3.18 50 2.80 2.89E-03 2.94 55 3.02 3.12E-03 2.73 60 3.24 3.34E-03 2.54 65 3.45 3.56E-03 2.38 70 3.67 3.79E-03 2.24 75 3.89 4.01E-03 2.12 80 4.10 4.23E-03 2.01 85 4.32 4.46E-03 1.91 90 4.53 4.68E-03 1.81 95 4.75 4.90E-03 1.73 100 4.97 5.13E-03 1.66 105 5.18 5.35E-03 1.59 110 5.40 5.58E-03 1.52 115 5.62 5.80E-03 1.46 120 5.83 6.02E-03 1.4156 Microturbine III Senior Design 05002C. Appendix C – Mass Flow Calculation Inputs: Pressure 800 R 661.92 T 537 mass 0.03 Volume 13.32941 density 0.002251 mass flow rate 0.000153Time Mass Flow (s) Mass (lbs) Density Po (psi) To ® Rate 0 0.03 0.002250662 800 537 0.000152993 0.1 0.029984701 0.002249514 799.5920185 537 0.000152993 0.2 0.029969401 0.002248366 799.1840369 537 0.000152993 0.3 0.029954102 0.002247218 798.7760554 537 0.000152993 0.4 0.029938803 0.00224607 798.3680739 537 0.000152993 0.5 0.029923503 0.002244923 797.9600924 537 0.000152993 0.6 0.029908204 0.002243775 797.5521108 537 0.000152993 0.7 0.029892905 0.002242627 797.1441293 537 0.000152993 0.8 0.029877606 0.002241479 796.7361478 537 0.000152993 0.9 0.029862306 0.002240332 796.3281662 537 0.000152993 1 0.029847007 0.002239184 795.9201847 537 0.000152993 1.1 0.029831708 0.002238036 795.5122032 537 0.000152993 1.2 0.029816408 0.002236888 795.1042217 537 0.000152993 1.3 0.029801109 0.00223574 794.6962401 537 0.000152993 1.4 0.02978581 0.002234593 794.2882586 537 0.000152993 1.5 0.02977051 0.002233445 793.8802771 537 0.000152993 1.6 0.029755211 0.002232297 793.4722955 537 0.000152993 1.7 0.029739912 0.002231149 793.064314 537 0.000152993 160.7 0.005414013 0.00040617 144.3736836 537 0.000152993 160.8 0.005398714 0.000405023 143.965702 537 0.000152993 160.9 0.005383415 0.000403875 143.5577205 537 0.000152993 161 0.005368115 0.000402727 143.149739 537 0.000152993 179 0.00261424 0.000196126 69.71306384 537 0.000152993 179.1 0.002598941 0.000194978 69.30508231 537 0.000152993 179.2 0.002583641 0.00019383 68.89710079 537 0.000152993 179.3 0.002568342 0.000192682 68.48911926 537 0.000152993 179.4 0.002553043 0.000191535 68.08113773 537 0.000152993 179.5 0.002537743 0.000190387 67.6731562 537 0.000152993 179.6 0.002522444 0.000189239 67.26517467 537 0.000152993 179.7 0.002507145 0.000188091 66.85719314 537 0.000152993 179.8 0.002491845 0.000186943 66.44921161 537 0.000152993 179.9 0.002476546 0.000185796 66.04123009 537 0.000152993 180 0.002461247 0.000184648 65.63324856 537 0.00015299357 Microturbine III Senior Design 05002D. Appendix D – Finite Element Analysis On Housing / Cap58 Microturbine III Senior Design 0500259 Microturbine III Senior Design 05002The above seen boundary conditions were set upon the housing cap in order to test for failure under the worst case scenario of 300 psi. A 300 psi pressure was placed on the contacting face, side below the o-ring, and also the contact area for the bearing due to a pressure on the bearing. Boundary conditions on the cap were placed such that the sides of the cap as well as the bearing hole were constrained from moving in the radial direction due to the fact that the housing and bearing will help to hold these constraints. The holes for the retaining bolts were constrained to simulate the bolts holding the cap into the housing, which is visible in the deflection under loading. The maximum stress seen under these conditions was determined to be3740 psi, which falls within the maximum tensile strength of the reinforced nylon of 11,500 psi.60 Microturbine III Senior Design 0500261 Microturbine III Senior Design 0500262 Microturbine III Senior Design 05002E. Appendix E – Turbine Performance Data63 Microturbine III Senior Design 0500264

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