Experimental Study of the Combustion Efficiency in Multi-Element Gas
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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. -
Turbopump Design and Analysis Approach for Nuclear Thermal Rockets
Turbopump Design and Analysis Approach for Nuclear Thermal Rockets Shu-cheng S. Chen1, Joseph P. Veres2, and James E. Fittje3 1NASA Glenn Research Center, Cleveland, Ohio 44135 2Chief, Compressor Branch, NASA Glenn Research Center, Cleveland, Ohio 44135 3Analex Corporation, 1100 Apollo Drive, Brook Park, Ohio 44142 1(216) 433-3585, [email protected] Abstract. A rocket propulsion system, whether it is a chemical rocket or a nuclear thermal rocket, is fairly complex in detail but rather simple in principle. Among all the interacting parts, three components stand out: they are pumps and turbines (turbopumps), and the thrust chamber. To obtain an understanding of the overall rocket propulsion system characteristics, one starts from analyzing the interactions among these three components. It is therefore of utmost importance to be able to satisfactorily characterize the turbopump, level by level, at all phases of a vehicle design cycle. Here at NASA Glenn Research Center, as the starting phase of a rocket engine design, specifically a Nuclear Thermal Rocket Engine design, we adopted the approach of using a high level system cycle analysis code (NESS) to obtain an initial analysis of the operational characteristics of a turbopump required in the propulsion system. A set of turbopump design codes (PumpDes and TurbDes) were then executed to obtain sizing and performance characteristics of the turbopump that were consistent with the mission requirements. A set of turbopump analyses codes (PUMPA and TURBA) were applied to obtain the full performance map for each of the turbopump components; a two dimensional layout of the turbopump based on these mean line analyses was also generated. -
Development of Turbopump for LE-9 Engine
Development of Turbopump for LE-9 Engine MIZUNO Tsutomu : P. E. Jp, Manager, Research & Engineering Development, Aero Engine, Space & Defense Business Area OGUCHI Hideo : Manager, Space Development Department, Aero Engine, Space & Defense Business Area NIIYAMA Kazuki : Ph. D., Manager, Space Development Department, Aero Engine, Space & Defense Business Area SHIMIYA Noriyuki : Space Development Department, Aero Engine, Space & Defense Business Area LE-9 is a new cryogenic booster engine with high performance, high reliability, and low cost, which is designed for H3 Rocket. It will be the first booster engine in the world with an expander bleed cycle. In the designing process, the performance requirements of the turbopump and other components can be concurrently evaluated by the mathematical model of the total engine system including evaluation with the simulated performance characteristic model of turbopump. This paper reports the design requirements of the LE-9 turbopump and their latest development status. Liquid oxygen 1. Introduction turbopump Liquid hydrogen The H3 rocket, intended to reduce cost and improve turbopump reliability with respect to the H-II A/B rockets currently in operation, is under development toward the launch of the first H3 test rocket in FY 2020. In rocket development, engine is an important factor determining reliability, cost, and performance, and as a new engine for the H3 rocket first stage, an LE-9 engine(1) is under development. A rocket engine uses a turbopump to raise the pressure of low-pressure propellant supplied from a tank, injects the pressurized propellant through an injector into a combustion chamber to combust it under high-temperature and high- pressure conditions. -
Investigation of Condensed and Early Stage Gas Phase Hypergolic Reactions Jacob Daniel Dennis Purdue University
Purdue University Purdue e-Pubs Open Access Dissertations Theses and Dissertations Fall 2014 Investigation of condensed and early stage gas phase hypergolic reactions Jacob Daniel Dennis Purdue University Follow this and additional works at: https://docs.lib.purdue.edu/open_access_dissertations Part of the Propulsion and Power Commons Recommended Citation Dennis, Jacob Daniel, "Investigation of condensed and early stage gas phase hypergolic reactions" (2014). Open Access Dissertations. 256. https://docs.lib.purdue.edu/open_access_dissertations/256 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. i INVESTIGATION OF CONDENSED AND EARLY STAGE GAS PHASE HYPERGOLIC REACTIONS A Dissertation Submitted to the Faculty of Purdue University by Jacob Daniel Dennis In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy December 2014 Purdue University West Lafayette, Indiana ii To my parents, Jay and Susan Dennis, who have always pushed me to be the person they know I am capable of being. Also to my wife, Claresta Dennis, who not only tolerated me but suffered along with me throughout graduate school. I love you and am so proud of you! iii ACKNOWLEDGEMENTS I would like to express my sincere gratitude to my advisor, Dr. Timothée Pourpoint, for guiding me over the past four years and helping me become the researcher that I am today. In addition I would like to thank the rest of my PhD Committee for the insight and guidance. I would also like to acknowledge the help provided by my fellow graduate students who spent time with me in the lab: Travis Kubal, Yair Solomon, Robb Janesheski, Jordan Forness, Jonathan Chrzanowski, Jared Willits, and Jason Gabl. -
The SKYLON Spaceplane
The SKYLON Spaceplane Borg K.⇤ and Matula E.⇤ University of Colorado, Boulder, CO, 80309, USA This report outlines the major technical aspects of the SKYLON spaceplane as a final project for the ASEN 5053 class. The SKYLON spaceplane is designed as a single stage to orbit vehicle capable of lifting 15 mT to LEO from a 5.5 km runway and returning to land at the same location. It is powered by a unique engine design that combines an air- breathing and rocket mode into a single engine. This is achieved through the use of a novel lightweight heat exchanger that has been demonstrated on a reduced scale. The program has received funding from the UK government and ESA to build a full scale prototype of the engine as it’s next step. The project is technically feasible but will need to overcome some manufacturing issues and high start-up costs. This report is not intended for publication or commercial use. Nomenclature SSTO Single Stage To Orbit REL Reaction Engines Ltd UK United Kingdom LEO Low Earth Orbit SABRE Synergetic Air-Breathing Rocket Engine SOMA SKYLON Orbital Maneuvering Assembly HOTOL Horizontal Take-O↵and Landing NASP National Aerospace Program GT OW Gross Take-O↵Weight MECO Main Engine Cut-O↵ LACE Liquid Air Cooled Engine RCS Reaction Control System MLI Multi-Layer Insulation mT Tonne I. Introduction The SKYLON spaceplane is a single stage to orbit concept vehicle being developed by Reaction Engines Ltd in the United Kingdom. It is designed to take o↵and land on a runway delivering 15 mT of payload into LEO, in the current D-1 configuration. -
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. -
Rocket Propulsion Fundamentals 2
https://ntrs.nasa.gov/search.jsp?R=20140002716 2019-08-29T14:36:45+00:00Z Liquid Propulsion Systems – Evolution & Advancements Launch Vehicle Propulsion & Systems LPTC Liquid Propulsion Technical Committee Rick Ballard Liquid Engine Systems Lead SLS Liquid Engines Office NASA / MSFC All rights reserved. No part of this publication may be reproduced, distributed, or transmitted, unless for course participation and to a paid course student, in any form or by any means, or stored in a database or retrieval system, without the prior written permission of AIAA and/or course instructor. Contact the American Institute of Aeronautics and Astronautics, Professional Development Program, Suite 500, 1801 Alexander Bell Drive, Reston, VA 20191-4344 Modules 1. Rocket Propulsion Fundamentals 2. LRE Applications 3. Liquid Propellants 4. Engine Power Cycles 5. Engine Components Module 1: Rocket Propulsion TOPICS Fundamentals • Thrust • Specific Impulse • Mixture Ratio • Isp vs. MR • Density vs. Isp • Propellant Mass vs. Volume Warning: Contents deal with math, • Area Ratio physics and thermodynamics. Be afraid…be very afraid… Terms A Area a Acceleration F Force (thrust) g Gravity constant (32.2 ft/sec2) I Impulse m Mass P Pressure Subscripts t Time a Ambient T Temperature c Chamber e Exit V Velocity o Initial state r Reaction ∆ Delta / Difference s Stagnation sp Specific ε Area Ratio t Throat or Total γ Ratio of specific heats Thrust (1/3) Rocket thrust can be explained using Newton’s 2nd and 3rd laws of motion. 2nd Law: a force applied to a body is equal to the mass of the body and its acceleration in the direction of the force. -
A Comparison of Combustor-Noise Models – AIAA 2012-2087
A Comparison of Combustor-Noise Models – AIAA 2012-2087 Lennart S. Hultgren, NASA Glenn Research Center, Cleveland, OH 44135 Summary The present status of combustor-noise prediction in the NASA Aircraft Noise Prediction Program (ANOPP)1 for current- generation (N) turbofan engines is summarized. Several semi-empirical models for turbofan combustor noise are discussed, including best methods for near-term updates to ANOPP. An alternate turbine-transmission factor2 will appear as a user selectable option in the combustor-noise module GECOR in the next release. The three-spectrum model proposed by Stone et al.3 for GE turbofan-engine combustor noise is discussed and compared with ANOPP predictions for several relevant cases. Based on the results presented herein and in their report,3 it is recommended that the application of this fully empirical combustor-noise prediction method be limited to situations involving only General-Electric turbofan engines. Long-term needs and challenges for the N+1 through N+3 time frame are discussed. Because the impact of other propulsion-noise sources continues to be reduced due to turbofan design trends, advances in noise-mitigation techniques, and expected aircraft configuration changes, the relative importance of core noise is expected to greatly increase in the future. The noise-source structure in the combustor, including the indirect one, and the effects of the propagation path through the engine and exhaust nozzle need to be better understood. In particular, the acoustic consequences of the expected trends toward smaller, highly efficient gas- generator cores and low-emission fuel-flexible combustors need to be fully investigated since future designs are quite likely to fall outside of the parameter space of existing (semi-empirical) prediction tools. -
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. -
6. Chemical-Nuclear Propulsion MAE 342 2016
2/12/20 Chemical/Nuclear Propulsion Space System Design, MAE 342, Princeton University Robert Stengel • Thermal rockets • Performance parameters • Propellants and propellant storage Copyright 2016 by Robert Stengel. All rights reserved. For educational use only. http://www.princeton.edu/~stengel/MAE342.html 1 1 Chemical (Thermal) Rockets • Liquid/Gas Propellant –Monopropellant • Cold gas • Catalytic decomposition –Bipropellant • Separate oxidizer and fuel • Hypergolic (spontaneous) • Solid Propellant ignition –Mixed oxidizer and fuel • External ignition –External ignition • Storage –Burn to completion – Ambient temperature and pressure • Hybrid Propellant – Cryogenic –Liquid oxidizer, solid fuel – Pressurized tank –Throttlable –Throttlable –Start/stop cycling –Start/stop cycling 2 2 1 2/12/20 Cold Gas Thruster (used with inert gas) Moog Divert/Attitude Thruster and Valve 3 3 Monopropellant Hydrazine Thruster Aerojet Rocketdyne • Catalytic decomposition produces thrust • Reliable • Low performance • Toxic 4 4 2 2/12/20 Bi-Propellant Rocket Motor Thrust / Motor Weight ~ 70:1 5 5 Hypergolic, Storable Liquid- Propellant Thruster Titan 2 • Spontaneous combustion • Reliable • Corrosive, toxic 6 6 3 2/12/20 Pressure-Fed and Turbopump Engine Cycles Pressure-Fed Gas-Generator Rocket Rocket Cycle Cycle, with Nozzle Cooling 7 7 Staged Combustion Engine Cycles Staged Combustion Full-Flow Staged Rocket Cycle Combustion Rocket Cycle 8 8 4 2/12/20 German V-2 Rocket Motor, Fuel Injectors, and Turbopump 9 9 Combustion Chamber Injectors 10 10 5 2/12/20 -
Materials for Liquid Propulsion Systems
https://ntrs.nasa.gov/search.jsp?R=20160008869 2019-08-29T17:47:59+00:00Z CHAPTER 12 Materials for Liquid Propulsion Systems John A. Halchak Consultant, Los Angeles, California James L. Cannon NASA Marshall Space Flight Center, Huntsville, Alabama Corey Brown Aerojet-Rocketdyne, West Palm Beach, Florida 12.1 Introduction Earth to orbit launch vehicles are propelled by rocket engines and motors, both liquid and solid. This chapter will discuss liquid engines. The heart of a launch vehicle is its engine. The remainder of the vehicle (with the notable exceptions of the payload and guidance system) is an aero structure to support the propellant tanks which provide the fuel and oxidizer to feed the engine or engines. The basic principle behind a rocket engine is straightforward. The engine is a means to convert potential thermochemical energy of one or more propellants into exhaust jet kinetic energy. Fuel and oxidizer are burned in a combustion chamber where they create hot gases under high pressure. These hot gases are allowed to expand through a nozzle. The molecules of hot gas are first constricted by the throat of the nozzle (de-Laval nozzle) which forces them to accelerate; then as the nozzle flares outwards, they expand and further accelerate. It is the mass of the combustion gases times their velocity, reacting against the walls of the combustion chamber and nozzle, which produce thrust according to Newton’s third law: for every action there is an equal and opposite reaction. [1] Solid rocket motors are cheaper to manufacture and offer good values for their cost.