Pulsejet Engine Performance Estimation (Versão Revista Após Discussão)
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Study and Numerical Simulation of Unconventional Engine Technology
STUDY AND NUMERICAL SIMULATION OF UNCONVENTIONAL ENGINE TECHNOLOGY by ANJALI SHEKHAR B.E Aeronautical Engineering VTU, Karnataka, 2013 A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, Aerospace Engineering, College of Engineering and Applied Science, University of Cincinnati, Ohio 2018 Thesis Committee: Chair: Ephraim Gutmark, Ph.D. Member: Shaaban Abdallah, Ph.D. Member: Mark Turner, Sc.D. An Abstract of Study and Numerical Simulation of Unconventional Engine Technology by Anjali Shekhar Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Aerospace Engineering University of Cincinnati December 2018 The aim of this thesis is to understand the working of two unconventional aircraft propul- sion systems and to setup a two-dimensional transient simulation to analyze its operational mechanism. The air traffic has nearly increased by about 40% in past three decades and calls for alternative propulsion techniques to replace or support the current traditional propulsion methodology. In the light of current demand, the thesis draws motivation from renewed inter- est in two non-conventional propulsion techniques designed in the past and had not been given due importance due to various flaws/drawbacks associated. The thesis emphasizes on the work- ing of Von Ohains thermal compression engine and pulsejet combustors. Computational Fluid Dynamics is used in current study as it offers very high flexibility and can be modified easily to incorporate the required changes. Thermal Compression engine is a design suggested by Von Ohain in 1948. The engine works on the principle of pressure rise caused inside the engine which completely depends on the temperature of working fluid and independent of rotations per minute. -
Engineering Fundamentals of the Internal Combustion Engine
Engineering Fundamentals of the Internal Combustion Engine . I Willard W. Pulkrabek University of Wisconsin-· .. Platteville vi Contents 2-3 Mean Effective Pressure, 49 2-4 Torque and Power, 50 2-5 Dynamometers, 53 2-6 Air-Fuel Ratio and Fuel-Air Ratio, 55 2-7 Specific Fuel Consumption, 56 2-8 Engine Efficiencies, 59 2-9 Volumetric Efficiency, 60 , 2-10 Emissions, 62 2-11 Noise Abatement, 62 2-12 Conclusions-Working Equations, 63 Problems, 65 Design Problems, 67 3 ENGINE CYCLES 68 3-1 Air-Standard Cycles, 68 3-2 Otto Cycle, 72 3-3 Real Air-Fuel Engine Cycles, 81 3-4 SI Engine Cycle at Part Throttle, 83 3-5 Exhaust Process, 86 3-6 Diesel Cycle, 91 3-7 Dual Cycle, 94 3-8 Comparison of Otto, Diesel, and Dual Cycles, 97 3-9 Miller Cycle, 103 3-10 Comparison of Miller Cycle and Otto Cycle, 108 3-11 Two-Stroke Cycles, 109 3-12 Stirling Cycle, 111 3-13 Lenoir Cycle, 113 3-14 Summary, 115 Problems, 116 Design Problems, 120 4 THERMOCHEMISTRY AND FUELS 121 4-1 Thermochemistry, 121 4-2 Hydrocarbon Fuels-Gasoline, 131 4-3 Some Common Hydrocarbon Components, 134 4-4 Self-Ignition and Octane Number, 139 4-5 Diesel Fuel, 148 4-6 Alternate Fuels, 150 4-7 Conclusions, 162 Problems, 162 Design Problems, 165 Contents vii 5 AIR AND FUEL INDUCTION 166 5-1 Intake Manifold, 166 5-2 Volumetric Efficiency of SI Engines, 168 5-3 Intake Valves, 173 5-4 Fuel Injectors, 178 5-5 Carburetors, 181 5-6 Supercharging and Turbocharging, 190 5-7 Stratified Charge Engines and Dual Fuel Engines, 195 5-8 Intake for Two-Stroke Cycle Engines, 196 5-9 Intake for CI Engines, 199 -
Internal Combustion Engines Collection of Stationary
ASME International THE COOLSPRING POWER MUSEUM COLLECTION OF STATIONARY INTERNAL COMBUSTION ENGINES MECHANICAL ENGINEERING HERITAGE COLLECTION Coolspring Power Museum Coolspring, Pennsylvania June 16, 2001 The Coolspring Power Museu nternal combustion engines revolutionized the world I around the turn of th 20th century in much the same way that steam engines did a century before. One has only to imagine a coal-fired, steam-powered, air- plane to realize how important internal combustion was to the industrialized world. While the early gas engines were more expensive than the equivalent steam engines, they did not require a boiler and were cheap- er to operate. The Coolspring Power Museum collection documents the early history of the internal- combustion revolution. Almost all of the critical components of hundreds of innovations that 1897 Charter today’s engines have their ori- are no longer used). Some of Gas Engine gins in the period represented the engines represent real engi- by the collection (as well as neering progress; others are more the product of inventive minds avoiding previous patents; but all tell a story. There are few duplications in the collection and only a couple of manufacturers are represent- ed by more than one or two examples. The Coolspring Power Museum contains the largest collection of historically signifi- cant, early internal combustion engines in the country, if not the world. With the exception of a few items in the collection that 2 were driven by the engines, m Collection such as compressors, pumps, and generators, and a few steam and hot air engines shown for comparison purposes, the collection contains only internal combustion engines. -
Pyroelectric Energy Harvesting: with Thermodynamic-Based Cycles
Hindawi Publishing Corporation Smart Materials Research Volume 2012, Article ID 160956, 5 pages doi:10.1155/2012/160956 Research Article Pyroelectric Energy Harvesting: With Thermodynamic-Based Cycles Saber Mohammadi and Akram Khodayari Mechanical Engineering Department, School of Engineering, Razi University, Kermanshah 67149-67346, Iran Correspondence should be addressed to Saber Mohammadi, [email protected] Received 30 November 2011; Revised 31 January 2012; Accepted 2 February 2012 Academic Editor: Mickael¨ Lallart Copyright © 2012 S. Mohammadi and A. Khodayari. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This work deals with energy harvesting from temperature variations using ferroelectric materials as a microgenerator. The previous researches show that direct pyroelectric energy harvesting is not effective, whereas thermodynamic-based cycles give higher energy. Also, at different temperatures some thermodynamic cycles exhibit different behaviours. In this paper pyroelectric energy harvesting using Lenoir and Ericsson thermodynamic cycles has been studied numerically and the two cycles were compared with each other. The material used is the PMN-25 PT single crystal that is a very interesting material in the framework of energy harvesting and sensor applications. 1. Introduction for the systems with limited accessibility such as biomedical implants, structure embedded microsensors, or safety moni- Small, portable, and lightweight power generation systems toring devices. are currently in very high demand in commercial markets, Thermodielectric power generation utilizes the pyroelec- due to a dramatic increase in the use of personal electronics tric effect to convert heat to useful electricity. -
WPP Presentation
AE705 /153M/ 152 Introduction to Flight Fatima Salehbhai Third Year U G Student Mechanical Engg. Deptt. IIT Bombay Types of Propulsion Systems AE-705 Introduction to Flight Lecture No 11 Capsule-06 What is propulsion? • Moving or Pushing an object forward Propulsion = pro (forward) + pellere (drive) Why is propulsion needed in aircraft? • Getting aloft - thrust + lift • produces thrust to push an object • used to accelerate, gain altitude, and to maneuver AE-705 Introduction to Flight Lecture No 11 Capsule-06 Revising Thrust • Drives an airplane forward • To sustain lift and counteract drag http://howthingsfly.si.edu/media/thrust • Energy required • Heat by the combustion • Propulsion system • A machine that accelerates air backwards https://www.nasa.gov/audience/forstudents/k-4/stories /nasa-knows/what-is-aerodynamics-k4.html AE-705 Introduction to Flight Lecture No 11 Capsule-06 Propulsion Systems Mechanisms to produce thrust for flight AE-705 Introduction to Flight Lecture No 11 Capsule-06 Types of Propulsion Systems We'll discuss the following : • Pistonpropeller • Pulsejet • Turbojet • Ramjet • Afterburning Turbojet • Scramjet • Turbofan • Electric Propulsion • Turboprop • Ionic Propulsion • Turboshaft AE-705 Introduction to Flight Lecture No 11 Capsule-06 Powerplant Selection based on mission Source: D. P. Raymer, Aircraft Design, A Conceptual Approach, AIAA Education Series, 4th edition, 2006 AE-705 Introduction to Flight Lecture No 11 Capsule-06 Reciprocating Engines Primary powerplant for general aviation image source: https://www.comsol.com/blogs/improving-the-operational-lifetime-of-a-reciprocating-engine/ -
Study and Optimization of a Cad/Cfd Model for Valveless Pulsejets
VOL. 13, NO. 21, NOVEMBER 2018 ISSN 1819-6608 ARPN Journal of Engineering and Applied Sciences ©2006-2018 Asian Research Publishing Network (ARPN). All rights reserved. www.arpnjournals.com STUDY AND OPTIMIZATION OF A CAD/CFD MODEL FOR VALVELESS PULSEJETS Luca Piancastelli1, Stefano Cassani2, Eugenio Pezzuti3 and Luca Lipparini1 1Department of Industrial Engineering, Alma Mater Studiorum University of Bologna, Viale Risorgimento, Bologna (BO), Italy 2MultiProjecta, Via Casola Canina, Imola (BO), Italy 3Università di Roma "Tor Vergata", Dip. di Ingegneria dell’Impresa "Mario Lucertini”, Via del Politecnico, Roma, Italy E-Mail: [email protected] ABSTRACT The method introduced in this paper aims to find a feasible method to evaluate the static thrust of a “valveless” pulsejet, starting from a CAD model. CFD (Computational Fluid Dynamic) simulation and golden section were used for this purpose. Even for new pulsejet designs, it is possible to evaluate the pulsating frequency from equations available in literature or with a mono-dimensional pressure wave model. Then the combustion energy should be introduced in the engine. In this CFD model, the heat flow due to the combustion is simulated through the application of a pulsating flow of hot gases through the walls of the combustion chamber. To minimize the error of this added flow, a stoichiometric combustion of pure oxygen is introduced. The temperature value of the hot gases was optimized with the Golden Section Method in order to obtain the same experimental results of the Department of Aerospace Engineering of California Polytechnic State University, San Luis Obispo [2]. In this way, it is possible to evaluate the performance of a new design of different geometry and size. -
Constant Volume Combustion: the Ultimate Gas Turbine Cycle
INFRASTRUCTURE MINING & METALS NUCLEAR, SECURITY & ENVIRONMENTAL OIL, GAS & CHEMICALS Constant volume combustion: the ultimate gas turbine cycle About Bechtel Bechtel is among the most respected engineering, project management, and construction companies in the world. We stand apart for our ability to get the job done right—no matter how big, how complex, or how remote. Bechtel operates through four global business units that specialize in infrastructure; mining and metals; nuclear, security and environmental; and oil, gas, and chemicals. Since its founding in 1898, Bechtel has worked on more than 25,000 projects in 160 countries on all seven continents. Today, our 58,000 colleagues team with customers, partners, and suppliers on diverse projects in nearly 40 countries. Guest Feature Also in this section Constant volume combustion: 00 DARPA-funded CVC projects the ultimate gas turbine cycle 00 Power cycle thermodynamics 00 History of CVC engineering By S. C. Gülen, PhD, PE; Principal Engineer, Bechtel Power Pulse detonation combustion holds the key to 45% simple cycle and close to 65% combined cycle efficiencies at today’s 1400-1500°C gas turbine firing temperatures. The Kelvin-Planck statement of the Second Law of Thermo- Why constant volume combustion? dynamics leaves no room for doubt: the maximum efficiency In a modern gas turbine with an approximately constant pres- of a heat engine operating in a thermodynamic cycle cannot sure combustor, the compressor section consumes close to exceed the efficiency of a Carnot cycle operating between 50% of gas turbine power output. the same hot and cold temperature reservoirs. Assume one could devise a combustion system where All practical heat engine cycles are attempts to approxi- energy added to the working fluid (i.e. -
Ejector Enhanced Pulsejet Based Pressure Gain Combustors: an Old Idea with a New Twist
NASA/TM—2005-213854 AIAA–2005–4216 Ejector Enhanced Pulsejet Based Pressure Gain Combustors: An Old Idea With a New Twist Daniel E. Paxson Glenn Research Center, Cleveland, Ohio Kevin T. Dougherty QSS Group, Inc., Cleveland, Ohio August 2005 The NASA STI Program Office . in Profile Since its founding, NASA has been dedicated to • CONFERENCE PUBLICATION. Collected the advancement of aeronautics and space papers from scientific and technical science. The NASA Scientific and Technical conferences, symposia, seminars, or other Information (STI) Program Office plays a key part meetings sponsored or cosponsored by in helping NASA maintain this important role. NASA. The NASA STI Program Office is operated by • SPECIAL PUBLICATION. Scientific, Langley Research Center, the Lead Center for technical, or historical information from NASA’s scientific and technical information. The NASA programs, projects, and missions, NASA STI Program Office provides access to the often concerned with subjects having NASA STI Database, the largest collection of substantial public interest. aeronautical and space science STI in the world. The Program Office is also NASA’s institutional • TECHNICAL TRANSLATION. English- mechanism for disseminating the results of its language translations of foreign scientific research and development activities. These results and technical material pertinent to NASA’s are published by NASA in the NASA STI Report mission. Series, which includes the following report types: Specialized services that complement the STI • TECHNICAL PUBLICATION. Reports of Program Office’s diverse offerings include completed research or a major significant creating custom thesauri, building customized phase of research that present the results of databases, organizing and publishing research NASA programs and include extensive data results . -
Temperature Oscillations in the Wall of a Cooled Multi Pulsejet Propeller For
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Sheffield Hallam University Research Archive Temperature oscillations in the wall of a cooled multi pulsejet propeller for aeronautic propulsion TRANCOSSI, Michele, PASCOA, Jose and CARLOS, Xisto Available from Sheffield Hallam University Research Archive (SHURA) at: http://shura.shu.ac.uk/13964/ This document is the author deposited version. You are advised to consult the publisher's version if you wish to cite from it. Published version TRANCOSSI, Michele, PASCOA, Jose and CARLOS, Xisto (2016). Temperature oscillations in the wall of a cooled multi pulsejet propeller for aeronautic propulsion. SAE Technical Papers, 2016 (1-1998), 1-8. Repository use policy Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Users may download and/or print one copy of any article(s) in SHURA to facilitate their private study or for non- commercial research. You may not engage in further distribution of the material or use it for any profit-making activities or any commercial gain. Sheffield Hallam University Research Archive http://shura.shu.ac.uk Downloaded from SAE International by Michele Trancossi, Monday, November 07, 2016 Temperature Oscillations in the Wall of a Cooled Multi 2016-01-1998 Pulsejet Propeller for Aeronautic Propulsion Published 09/20/2016 Michele Trancossi Shefield Hallam University Jose Pascoa Universidade Da Beira Interior Carlos Xisto Chalmers University of Technology CITATION: Trancossi, M., Pascoa, J., and Xisto , C., "Temperature Oscillations in the Wall of a Cooled Multi Pulsejet Propeller for Aeronautic Propulsion," SAE Technical Paper 2016-01-1998, 2016, doi:10.4271/2016-01-1998. -
Centimeter Valveless Pulsejets at Low Subsonic Flight Speeds
ABSTRACT BOYETTE, WESLEY RYAN. Thrust and Specific Impulse Optimization of Eight- Centimeter Valveless Pulsejets at Low Subsonic Flight Speeds. (Under the direction of Dr. William L. Roberts). The purpose of this research was to develop a method of accurately measuring the thrust and specific impulse of valveless pulsejets that are approximately eight centimeters in length. Previous methods of doing such were largely unsuccessful. A vertically arranged thrust stand and electronic balance were ultimately able to produce reliable results. Seven inlets were then tested on a forward facing arrangement. The maximum thrust achieved was 24.4 mN and specific impulse peaked at 295 seconds. Comparison revealed that increasing inlet length has a positive effect on pulsejet performance. Each inlet was tested at simulated forward flight speeds as well, showing that shorter inlets perform optimally at lower speeds than longer inlets. Additionally, a relationship between pulsejet performance, frequency and exhaust temperature was identified. Similar tests were performed on hybrid configurations as well, which combine forward- facing and rearward-facing inlets. Of the five hybrid configurations tested, maximum thrust was 31.2 mN and maximum specific impulse was 232 seconds. This series of tests revealed that these configurations also showed improvement in performance at higher forward flight speeds and at smaller inlet areas. In all cases, hydrogen was used as the fuel, due to its very short chemical time. Pulsejets at this scale are also shown to be capable of operating on acetylene, although with reduced performance. Thrust and Specific Impulse Optimization of Eight-Centimeter Valveless Pulsejets at Low Subsonic Flight Speeds by Wesley Ryan Boyette A thesis submitted to the Graduate Faculty of North Carolina State University in partial fulfillment of the requirements for the Degree of Master of Science Aerospace Engineering Raleigh, North Carolina 2008 APPROVED BY: Dr. -
Combustion of Acetylene and Its Performance in Valveless Pulse Jet
Published by : International Journal of Engineering Research & Technology (IJERT) http://www.ijert.org ISSN: 2278-0181 Vol. 5 Issue 06, June-2016 Combustion of Acetylene and its Performance in Valveless Pulse Jet Engine M. Dhananiya Lakshmi Sri L. Oblisamy PG Scholar Assistant Professor Department of Aeronautical Engineering Department of Aeronautical Engineering Nehru Institute of Engineering and Technology Nehru Institute of Engineering and Technology Coimbatore, Tamil Nadu Coimbatore, Tamil Nadu G. Mari Prabu Assistant Professor Department of Aeronautical Engineering Sri Shakthi Institute of Engineering and Technology Coimbatore, Tamil Nadu Abstract—This paper summarizes the significance of barriers engine). Decreases non-linearly with decreasing characteristic involved in using acetylene as alternate fuel for valve less pulse engine length scale. Also, small scale engines with moving jet engine. Acetylene gas produces 2210 to 3300 degree Celsius parts are more prone to breakdown due to fatigue of the temperatures when allowed to combust with atmospheric air. moving components. Pulsejets, especially valveless The idea of high temperature engines is innovatory due to water pulsejets, are attractive as candidates for miniaturization due thermolysis which could accompany the combustion of to their extremely simple design.[7] acetylene. The use of acetylene will reduce emission and increase combustion efficiency. The project investigates the process of combustion of acetylene stoichiometrically with atmospheric air and also with oxygen computationally with the ANSYS Fluent commercial software in a valve less Bailey Machine Services hobby scale pulse jet of 15 centimeter class. The measurement of Pressure, thrust, temperature and concentrations of Carbon monoxide, Nitrous oxide and Hydrocarbons at the exit of pulse jet with acetylene and water thermolysis, Acetylene without water thermolysis and aviation gas without water thermolysis is analyzed and calculated. -
BASIC THERMODYNAMICS REFERENCES: ENGINEERING THERMODYNAMICS by P.K.NAG 3RD EDITION LAWS of THERMODYNAMICS
Module I BASIC THERMODYNAMICS REFERENCES: ENGINEERING THERMODYNAMICS by P.K.NAG 3RD EDITION LAWS OF THERMODYNAMICS • 0 th law – when a body A is in thermal equilibrium with a body B, and also separately with a body C, then B and C will be in thermal equilibrium with each other. • Significance- measurement of property called temperature. A B C Evacuated tube 100o C Steam point Thermometric property 50o C (physical characteristics of reference body that changes with temperature) – rise of mercury in the evacuated tube 0o C bulb Steam at P =1ice atm T= 30oC REASONS FOR NOT TAKING ICE POINT AND STEAM POINT AS REFERENCE TEMPERATURES • Ice melts fast so there is a difficulty in maintaining equilibrium between pure ice and air saturated water. Pure ice Air saturated water • Extreme sensitiveness of steam point with pressure TRIPLE POINT OF WATER AS NEW REFERENCE TEMPERATURE • State at which ice liquid water and water vapor co-exist in equilibrium and is an easily reproducible state. This point is arbitrarily assigned a value 273.16 K • i.e. T in K = 273.16 X / Xtriple point • X- is any thermomertic property like P,V,R,rise of mercury, thermo emf etc. OTHER TYPES OF THERMOMETERS AND THERMOMETRIC PROPERTIES • Constant volume gas thermometers- pressure of the gas • Constant pressure gas thermometers- volume of the gas • Electrical resistance thermometer- resistance of the wire • Thermocouple- thermo emf CELCIUS AND KELVIN(ABSOLUTE) SCALE H Thermometer 2 Ar T in oC N Pg 2 O2 gas -273 oC (0 K) Absolute pressure P This absolute 0K cannot be obtatined (Pg+Patm) since it violates third law.