Analysis of an After Burner in a Jet Engine
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Failure Analysis of Gas Turbine Blades in a Gas Turbine Engine Used for Marine Applications
INTERNATIONAL JOURNAL OF International Journal of Engineering, Science and Technology MultiCraft ENGINEERING, Vol. 6, No. 1, 2014, pp. 43-48 SCIENCE AND TECHNOLOGY www.ijest-ng.com www.ajol.info/index.php/ijest © 2014 MultiCraft Limited. All rights reserved Failure analysis of gas turbine blades in a gas turbine engine used for marine applications V. Naga Bhushana Rao1*, I. N. Niranjan Kumar2, K. Bala Prasad3 1* Department of Marine Engineering, Andhra University College of Engineering, Visakhapatnam, INDIA 2 Department of Marine Engineering, Andhra University College of Engineering, Visakhapatnam, INDIA 3 Department of Marine Engineering, Andhra University College of Engineering, Visakhapatnam, INDIA *Corresponding Author: e-mail: [email protected] Tel +91-8985003487 Abstract High pressure temperature (HPT) turbine blade is the most important component of the gas turbine and failures in this turbine blade can have dramatic effect on the safety and performance of the gas turbine engine. This paper presents the failure analysis made on HPT turbine blades of 100 MW gas turbine used in marine applications. The gas turbine blade was made of Nickel based super alloys and was manufactured by investment casting method. The gas turbine blade under examination was operated at elevated temperatures in corrosive environmental attack such as oxidation, hot corrosion and sulphidation etc. The investigation on gas turbine blade included the activities like visual inspection, determination of material composition, microscopic examination and metallurgical analysis. Metallurgical examination reveals that there was no micro-structural damage due to blade operation at elevated temperatures. It indicates that the gas turbine was operated within the designed temperature conditions. It was observed that the blade might have suffered both corrosion (including HTHC & LTHC) and erosion. -
Progress and Challenges in Liquid Rocket Combustion Stability Modeling
Seventh International Conference on ICCFD7-3105 Computational Fluid Dynamics (ICCFD7), Big Island, Hawaii, July 9-13, 2012 Progress and Challenges in Liquid Rocket Combustion Stability Modeling V. Sankaran∗, M. Harvazinski∗∗, W. Anderson∗∗ and D. Talley∗ Corresponding author: [email protected] ∗ Air Force Research Laboratory, Edwards AFB, CA, USA ∗∗ Purdue University, West Lafayette, IN, USA Abstract: Progress and challenges in combustion stability modeling in rocket engines are con- sidered using a representative longitudinal mode combustor developed at Purdue University. The CVRC or Continuously Variable Resonance Chamber has a translating oxidizer post that can be used to tune the resonant modes in the chamber with the combustion response leading to self- excited high-amplitude pressure oscillations. The three-dimensional hybrid RANS-LES model is shown to be capable of accurately predicting the self-excited instabilities. The frequencies of the dominant rst longitudinal mode as well as the higher harmonics are well-predicted and their rel- ative amplitudes are also reasonably well-captured. Post-processing the data to obtain the spatial distribution of the Rayleigh index shows the existence of large regions of positive coupling be- tween the heat release and the pressure oscillations. Dierences in the Rayleigh index distribution between the fuel-rich and fuel-lean cases appears to correlate well with the observation that the fuel-rich case is more unstable than the fuel-lean case. Keywords: Combustion Instability, Liquid Rocket Engines, Reacting Flow. 1 Introduction Combustion stability presents a major challenge to the design and development of liquid rocket engines. Instabilities are usually the result of a coupling between the combustion dynamics and the acoustics in the combustion chamber. -
Stall/Surge Dynamics of a Multi-Stage Air Compressor in Response to a Load Transient of a Hybrid Solid Oxide Fuel Cell-Gas Turbine System
Journal of Power Sources 365 (2017) 408e418 Contents lists available at ScienceDirect Journal of Power Sources journal homepage: www.elsevier.com/locate/jpowsour Stall/surge dynamics of a multi-stage air compressor in response to a load transient of a hybrid solid oxide fuel cell-gas turbine system * Mohammad Ali Azizi, Jacob Brouwer Advanced Power and Energy Program, University of California, Irvine, USA highlights Dynamic operation of a hybrid solid oxide fuel cell gas turbine system was explored. Computational fluid dynamic simulations of a multi-stage compressor were accomplished. Stall/surge dynamics in response to a pressure perturbation were evaluated. The multi-stage radial compressor was found robust to the pressure dynamics studied. Air flow was maintained positive without entering into severe deep surge conditions. article info abstract Article history: A better understanding of turbulent unsteady flows in gas turbine systems is necessary to design and Received 14 August 2017 control compressors for hybrid fuel cell-gas turbine systems. Compressor stall/surge analysis for a 4 MW Accepted 4 September 2017 hybrid solid oxide fuel cell-gas turbine system for locomotive applications is performed based upon a 1.7 MW multi-stage air compressor. Control strategies are applied to prevent operation of the hybrid SOFC-GT beyond the stall/surge lines of the compressor. Computational fluid dynamics tools are used to Keywords: simulate the flow distribution and instabilities near the stall/surge line. The results show that a 1.7 MW Solid oxide fuel cell system compressor like that of a Kawasaki gas turbine is an appropriate choice among the industrial Hybrid fuel cell gas turbine Dynamic simulation compressors to be used in a 4 MW locomotive SOFC-GT with topping cycle design. -
Propulsion Controls at NASA Lewis
Aircraft Turbine Engine Control Research at NASA Glenn Research Center Dr. Sanjay Garg Chief, Intelligent Control and Autonomy Branch Ph: (216) 433-2685 FAX: (216) 433-8990 email: [email protected] http://www.grc.nasa.gov/WWW/cdtb Glenn Research Center Intelligent Control and Autonomy Branch at Lewis Field Outline – The Engine Control Problem • Safety and Operational Limits • State-of-the-Art Engine Control Logic Architecture – Historical Glenn Research Center Contributions • Early Stages of Turbine Engine Control (1945-1960s) • Maturation of Turbine Engine Control (1970-1990) – Advanced Engine Control Research • Recent Significant Accomplishments (1990- 2004) • Current Research (2004 onwards) – Conclusion Glenn Research Center Intelligent Control and Autonomy Branch at Lewis Field Basic Engine Control Concept • Objective: Provide smooth, stable, and stall free operation of the engine via single input (PLA) with no throttle restrictions • Reliable and predictable throttle movement to thrust response • Issues: • Thrust cannot be measured • Changes in ambient condition and aircraft maneuvers cause distortion into the fan/compressor • Harsh operating environment – high temperatures and large vibrations • Safe operation – avoid stall, combustor blow out etc. • Need to provide long operating life – 20,000 hours • Engine components degrade with usage – need to have reliable performance throughout the operating life Glenn Research Center Intelligent Control and Autonomy Branch at Lewis Field Basic Engine Control Concept • Since Thrust (T) -
2.0 Axial-Flow Compressors 2.0-1 Introduction the Compressors in Most Gas Turbine Applications, Especially Units Over 5MW, Use Axial fl Ow Compressors
2.0 Axial-Flow Compressors 2.0-1 Introduction The compressors in most gas turbine applications, especially units over 5MW, use axial fl ow compressors. An axial fl ow compressor is one in which the fl ow enters the compressor in an axial direction (parallel with the axis of rotation), and exits from the gas turbine, also in an axial direction. The axial-fl ow compressor compresses its working fl uid by fi rst accelerating the fl uid and then diffusing it to obtain a pressure increase. The fl uid is accelerated by a row of rotating airfoils (blades) called the rotor, and then diffused in a row of stationary blades (the stator). The diffusion in the stator converts the velocity increase gained in the rotor to a pressure increase. A compressor consists of several stages: 1) A combination of a rotor followed by a stator make-up a stage in a compressor; 2) An additional row of stationary blades are frequently used at the compressor inlet and are known as Inlet Guide Vanes (IGV) to ensue that air enters the fi rst-stage rotors at the desired fl ow angle, these vanes are also pitch variable thus can be adjusted to the varying fl ow requirements of the engine; and 3) In addition to the stators, another diffuser at the exit of the compressor consisting of another set of vanes further diffuses the fl uid and controls its velocity entering the combustors and is often known as the Exit Guide Vanes (EGV). In an axial fl ow compressor, air passes from one stage to the next, each stage raising the pressure slightly. -
Aerospace Engine Data
AEROSPACE ENGINE DATA Data for some concrete aerospace engines and their craft ................................................................................. 1 Data on rocket-engine types and comparison with large turbofans ................................................................... 1 Data on some large airliner engines ................................................................................................................... 2 Data on other aircraft engines and manufacturers .......................................................................................... 3 In this Appendix common to Aircraft propulsion and Space propulsion, data for thrust, weight, and specific fuel consumption, are presented for some different types of engines (Table 1), with some values of specific impulse and exit speed (Table 2), a plot of Mach number and specific impulse characteristic of different engine types (Fig. 1), and detailed characteristics of some modern turbofan engines, used in large airplanes (Table 3). DATA FOR SOME CONCRETE AEROSPACE ENGINES AND THEIR CRAFT Table 1. Thrust to weight ratio (F/W), for engines and their crafts, at take-off*, specific fuel consumption (TSFC), and initial and final mass of craft (intermediate values appear in [kN] when forces, and in tonnes [t] when masses). Engine Engine TSFC Whole craft Whole craft Whole craft mass, type thrust/weight (g/s)/kN type thrust/weight mini/mfin Trent 900 350/63=5.5 15.5 A380 4×350/5600=0.25 560/330=1.8 cruise 90/63=1.4 cruise 4×90/5000=0.1 CFM56-5A 110/23=4.8 16 -
Propulsion Systems for Aircraft. Aerospace Education II
. DOCUMENT RESUME ED 111 621 SE 017 458 AUTHOR Mackin, T. E. TITLE Propulsion Systems for Aircraft. Aerospace Education II. INSTITUTION 'Air Univ., Maxwell AFB, Ala. Junior Reserve Office Training Corps.- PUB.DATE 73 NOTE 136p.; Colored drawings may not reproduce clearly. For the accompanying Instructor Handbook, see SE 017 459. This is a revised text for ED 068 292 EDRS PRICE, -MF-$0.76 HC.I$6.97 Plus' Postage DESCRIPTORS *Aerospace 'Education; *Aerospace Technology;'Aviation technology; Energy; *Engines; *Instructional-. Materials; *Physical. Sciences; Science Education: Secondary Education; Textbooks IDENTIFIERS *Air Force Junior ROTC ABSTRACT This is a revised text used for the Air Force ROTC _:_progralit._The main part of the book centers on the discussion -of the . engines in an airplane. After describing the terms and concepts of power, jets, and4rockets, the author describes reciprocating engines. The description of diesel engines helps to explain why theseare not used in airplanes. The discussion of the carburetor is followed byan explanation of the lubrication system. The chapter on reaction engines describes the operation of,jets, with examples of different types of jet engines.(PS) . 4,,!It********************************************************************* * Documents acquired by, ERIC include many informal unpublished * materials not available from other souxces. ERIC makes every effort * * to obtain the best copravailable. nevertheless, items of marginal * * reproducibility are often encountered and this affects the quality * * of the microfiche and hardcopy reproductions ERIC makes available * * via the ERIC Document" Reproduction Service (EDRS). EDRS is not * responsible for the quality of the original document. Reproductions * * supplied by EDRS are the best that can be made from the original. -
Dual-Mode Free-Jet Combustor
Dual-Mode Free-Jet Combustor Charles J. Trefny and Vance F. Dippold III [email protected] NASA Glenn Research Center Cleveland, Ohio USA Shaye Yungster Ohio Aerospace Institute Cleveland, Ohio USA ABSTRACT The dual-mode free-jet combustor concept is described. It was introduced in 2010 as a wide operating-range propulsion device using a novel supersonic free-jet combustion process. The unique feature of the free-jet combustor is supersonic combustion in an unconfined free-jet that traverses a larger subsonic combustion chamber to a variable throat area nozzle. During this mode of operation, the propulsive stream is not in contact with the combustor walls and equilibrates to the combustion chamber pressure. To a first order, thermodynamic efficiency is similar to that of a traditional scramjet under the assumption of constant-pressure combustion. Qualitatively, a number of possible benefits to this approach are as follows. The need for fuel staging is eliminated since the cross-sectional area distribution required for supersonic combustion is accommodated aerodynamically without regard for wall pressure gradients and boundary-layer separation. The unconstrained nature of the free-jet allows for consideration of a detonative combustion process that is untenable in a walled combustor. Heat loads, especially localized effects of shock wave / boundary-layer interactions, are reduced making possible the use of hydrocarbon fuels to higher flight Mach numbers. The initial motivation for this scheme however, was that the combustion chamber could be used for robust, subsonic combustion at low flight Mach numbers. At the desired flight condition, transition to free-jet mode would be effected by increasing the nozzle throat area and inducing separation at the diffuser inlet. -
Comparison of Helicopter Turboshaft Engines
Comparison of Helicopter Turboshaft Engines John Schenderlein1, and Tyler Clayton2 University of Colorado, Boulder, CO, 80304 Although they garnish less attention than their flashy jet cousins, turboshaft engines hold a specialized niche in the aviation industry. Built to be compact, efficient, and powerful, turboshafts have made modern helicopters and the feats they accomplish possible. First implemented in the 1950s, turboshaft geometry has gone largely unchanged, but advances in materials and axial flow technology have continued to drive higher power and efficiency from today's turboshafts. Similarly to the turbojet and fan industry, there are only a handful of big players in the market. The usual suspects - Pratt & Whitney, General Electric, and Rolls-Royce - have taken over most of the industry, but lesser known companies like Lycoming and Turbomeca still hold a footing in the Turboshaft world. Nomenclature shp = Shaft Horsepower SFC = Specific Fuel Consumption FPT = Free Power Turbine HPT = High Power Turbine Introduction & Background Turboshaft engines are very similar to a turboprop engine; in fact many turboshaft engines were created by modifying existing turboprop engines to fit the needs of the rotorcraft they propel. The most common use of turboshaft engines is in scenarios where high power and reliability are required within a small envelope of requirements for size and weight. Most helicopter, marine, and auxiliary power units applications take advantage of turboshaft configurations. In fact, the turboshaft plays a workhorse role in the aviation industry as much as it is does for industrial power generation. While conventional turbine jet propulsion is achieved through thrust generated by a hot and fast exhaust stream, turboshaft engines creates shaft power that drives one or more rotors on the vehicle. -
Turbofan Engine Malfunction Recognition and Response Final Report
07/17/09 Turbofan Engine Malfunction Recognition and Response Final Report Foreword This document summarizes the work done to develop generic text and video training material on the recognition and appropriate response to turbofan engine malfunctions, and to develop a simulator upgrade package improving the realism of engine malfunction simulation. This work was undertaken as a follow-on to the AIA/AECMA report on Propulsion System Malfunction Plus Inappropriate Crew Response (PSM+ICR), published in 1998, and implements some of the recommendations made in the PSM+ICR report. The material developed is closely based upon the PSM+ICR recommendations. The work was sponsored and co-chaired by the ATA and FAA. The organizations involved in preparation and review of the material included regulatory authorities, accident investigation authorities, pilot associations, airline associations, airline operators, training companies and airplane and engine manufacturers. The FAA is publishing the text and video material, and will make the simulator upgrade package available to interested parties. Reproduction and adaptation of the text and video material to meet the needs of individual operators is anticipated and encouraged. Copies may be obtained by contacting: FAA Engine & Propeller Directorate ANE-110 12 New England Executive Park Burlington, MA 01803 1 07/17/09 Contributing Organizations and Individuals Note: in order to expedite progress and maximize the participation of US airlines, it was decided to hold all meetings in North America. European regulators, manufacturers and operators were both invited to attend and informed of the progress of the work. Air Canada Capt. E Jokinen ATA Jim Mckie AirTran Capt. Robert Stienke Boeing Commercial Aircraft Van Winters CAE/ Flight Safety Boeing Capt. -
The Potential of Turboprops to Reduce Fuel Consumption in the Chinese Aviation System
THE POTENTIAL OF TURBOPROPS TO REDUCE FUEL CONSUMPTION IN THE CHINESE AVIATION SYSTEM Megan S. Ryerson, Xin Ge Department of City and Regional Planning Department of Electrical and Systems Engineering University of Pennsylvania [email protected] ICRAT 2014 Agenda • Introduction • Data collection • Turboprops in the current CAS network • Spatial trends for short-haul aviation • Regional jet and turboprop trade space • Turboprops in the future CAS network 2 1. Introduction – Growth of the Chinese Aviation System Number of Airports • The Chinese aviation system is in a period 300 of rapid growth • China’s civil aviation system grew at a rate 250 244 of 17.6%/year, 1980 - 2009 • Number of airports grew from 77 to 166 and annual traffic volume increasing from 3.43 million to 230 million 200 • The Civil Aviation Administration of China 166 (CAAC) maintains a target of 244 airports 150 across the country by 2020 • The CAAC plans for 80% of urban and suburban areas to be within a 100km (62 100 77 miles) of aviation service by 2020 • Plans also include strengthening hub-and- 50 spoke networks across the country to meet the dual goals of improving the competitiveness and efficiency of domestic 0 and international aviation. 1980 2009 2020 (Planned) 3 1. Introduction – Reform of the Chinese Aviation System • Consolidation Strong national hubs + insufficient regional coverage • Regional commuter airlines could fill this gap by partnering with China’s major carriers and serving the second-tier and emerging hubs (Shaw, 2009) 4 1. Introduction – Aircraft of the Short Haul Chinese Aviation System Narrow Body Jet Fuel per seat: 7.9 gal Regional Jet Fuel per seat: 19.0 gal Turboprop Fuel per seat: 4.35 gal 5 1. -
High Pressure Ratio Intercooled Turboprop Study
E AMEICA SOCIEY O MECAICA EGIEES 92-GT-405 4 E. 4 S., ew Yok, .Y. 00 h St hll nt b rpnbl fr ttnt r pnn dvnd In ppr r n d n t tn f th St r f t vn r Stn, r prntd In t pbltn. n rnt nl f th ppr pblhd n n ASME rnl. pr r vlbl fr ASME fr fftn nth ftr th tn. rntd n USA Copyright © 1992 by ASME ig essue aio Iecooe uoo Suy C. OGES Downloaded from http://asmedigitalcollection.asme.org/GT/proceedings-pdf/GT1992/78941/V002T02A028/2401669/v002t02a028-92-gt-405.pdf by guest on 23 September 2021 Sundstrand Power Systems San Diego, CA ASAC NOMENCLATURE High altitude long endurance unmanned aircraft impose KFT Altitude Thousands Feet unique contraints on candidate engine propulsion systems and HP Horsepower types. Piston, rotary and gas turbine engines have been proposed for such special applications. Of prime importance is the HIPIT High Pressure Intercooled Turbine requirement for maximum thermal efficiency (minimum specific Mn Flight Mach Number fuel consumption) with minimum waste heat rejection. Engine weight, although secondary to fuel economy, must be evaluated Mls Inducer Mach Number when comparing various engine candidates. Weight can be Specific Speed (Dimensionless) minimized by either high degrees of turbocharging with the Ns piston and rotary engines, or by the high power density Exponent capabilities of the gas turbine. pps Airflow The design characteristics and features of a conceptual high SFC Specific Fuel Consumption pressure ratio intercooled turboprop are discussed. The intended application would be for long endurance aircraft flying TIT Turbine Inlet Temperature °F at an altitude of 60,000 ft.(18,300 m).