Scaling of Performance in Liquid Propellant Rocket Engine Combustion Devices
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
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. -
Back to the the Future? 07> Probing the Kuiper Belt
SpaceFlight A British Interplanetary Society publication Volume 62 No.7 July 2020 £5.25 SPACE PLANES: back to the the future? 07> Probing the Kuiper Belt 634089 The man behind the ISS 770038 Remembering Dr Fred Singer 9 CONTENTS Features 16 Multiple stations pledge We look at a critical assessment of the way science is conducted at the International Space Station and finds it wanting. 18 The man behind the ISS 16 The Editor reflects on the life of recently Letter from the Editor deceased Jim Beggs, the NASA Administrator for whom the building of the ISS was his We are particularly pleased this supreme achievement. month to have two features which cover the spectrum of 22 Why don’t we just wing it? astronautical activities. Nick Spall Nick Spall FBIS examines the balance between gives us his critical assessment of winged lifting vehicles and semi-ballistic both winged and blunt-body re-entry vehicles for human space capsules, arguing that the former have been flight and Alan Stern reports on his grossly overlooked. research at the very edge of the 26 Parallels with Apollo 18 connected solar system – the Kuiper Belt. David Baker looks beyond the initial return to the We think of the internet and Moon by astronauts and examines the plan for a how it helps us communicate and sustained presence on the lunar surface. stay in touch, especially in these times of difficulty. But the fact that 28 Probing further in the Kuiper Belt in less than a lifetime we have Alan Stern provides another update on the gone from a tiny bleeping ball in pioneering work of New Horizons. -
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. -
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. -
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. -
Combustion Tap-Off Cycle
College of Engineering Honors Program 12-10-2016 Combustion Tap-Off Cycle Nicole Shriver Embry-Riddle Aeronautical University, [email protected] Follow this and additional works at: https://commons.erau.edu/pr-honors-coe Part of the Aeronautical Vehicles Commons, Other Aerospace Engineering Commons, Propulsion and Power Commons, and the Space Vehicles Commons Scholarly Commons Citation Shriver, N. (2016). Combustion Tap-Off Cycle. , (). Retrieved from https://commons.erau.edu/pr-honors- coe/6 This Article is brought to you for free and open access by the Honors Program at Scholarly Commons. It has been accepted for inclusion in College of Engineering by an authorized administrator of Scholarly Commons. For more information, please contact [email protected]. Honors Directed Study: Combustion Tap-Off Cycle Date of Submission: December 10, 2016 by Nicole Shriver [email protected] Submitted to Dr. Michael Fabian Department of Aerospace Engineering College of Engineering In Partial Fulfillment Of the Requirements Of Honors Directed Study Fall 2016 1 1.0 INTRODUCTION The combustion tap-off cycle is also known as the “topping cycle” or “chamber bleed cycle.” It is an open liquid bipropellant cycle, usually of liquid hydrogen and liquid oxygen, that combines the fuel and oxidizer in the main combustion chamber. Gases from the edges of the combustion chamber are used to power the engine’s turbine and are expelled as exhaust. Figure 1.1 below shows a picture representation of the cycle. Figure 1.1: Combustion Tap-Off Cycle The combustion tap-off cycle is rather unconventional for rocket engines as it has only been put into practice with two engines. -
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. -
Reduction of NO Emissions in a Turbojet Combustor by Direct Water
Reduction of NO emissions in a turbojet combustor by direct water/steam injection: numerical and experimental assessment Ernesto Benini, Sergio Pandolfo, Serena Zoppellari To cite this version: Ernesto Benini, Sergio Pandolfo, Serena Zoppellari. Reduction of NO emissions in a turbojet combus- tor by direct water/steam injection: numerical and experimental assessment. Applied Thermal Engi- neering, Elsevier, 2009, 29 (17-18), pp.3506. 10.1016/j.applthermaleng.2009.06.004. hal-00573476 HAL Id: hal-00573476 https://hal.archives-ouvertes.fr/hal-00573476 Submitted on 4 Mar 2011 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Accepted Manuscript Reduction of NO emissions in a turbojet combustor by direct water/steam in- jection: numerical and experimental assessment Ernesto Benini, Sergio Pandolfo, Serena Zoppellari PII: S1359-4311(09)00181-1 DOI: 10.1016/j.applthermaleng.2009.06.004 Reference: ATE 2830 To appear in: Applied Thermal Engineering Received Date: 10 November 2008 Accepted Date: 2 June 2009 Please cite this article as: E. Benini, S. Pandolfo, S. Zoppellari, Reduction of NO emissions in a turbojet combustor by direct water/steam injection: numerical and experimental assessment, Applied Thermal Engineering (2009), doi: 10.1016/j.applthermaleng.2009.06.004 This is a PDF file of an unedited manuscript that has been accepted for publication. -
2. Afterburners
2. AFTERBURNERS 2.1 Introduction The simple gas turbine cycle can be designed to have good performance characteristics at a particular operating or design point. However, a particu lar engine does not have the capability of producing a good performance for large ranges of thrust, an inflexibility that can lead to problems when the flight program for a particular vehicle is considered. For example, many airplanes require a larger thrust during takeoff and acceleration than they do at a cruise condition. Thus, if the engine is sized for takeoff and has its design point at this condition, the engine will be too large at cruise. The vehicle performance will be penalized at cruise for the poor off-design point operation of the engine components and for the larger weight of the engine. Similar problems arise when supersonic cruise vehicles are considered. The afterburning gas turbine cycle was an early attempt to avoid some of these problems. Afterburners or augmentation devices were first added to aircraft gas turbine engines to increase their thrust during takeoff or brief periods of acceleration and supersonic flight. The devices make use of the fact that, in a gas turbine engine, the maximum gas temperature at the turbine inlet is limited by structural considerations to values less than half the adiabatic flame temperature at the stoichiometric fuel-air ratio. As a result, the gas leaving the turbine contains most of its original concentration of oxygen. This oxygen can be burned with additional fuel in a secondary combustion chamber located downstream of the turbine where temperature constraints are relaxed. -
Validation of a Simplified Model for Liquid Propellant Rocket Engine Combustion Chamber Design
IOP Conference Series: Materials Science and Engineering PAPER • OPEN ACCESS Validation of a simplified model for liquid propellant rocket engine combustion chamber design To cite this article: M Hegazy et al 2020 IOP Conf. Ser.: Mater. Sci. Eng. 973 012003 View the article online for updates and enhancements. This content was downloaded from IP address 170.106.33.14 on 25/09/2021 at 23:25 AMME-19 IOP Publishing IOP Conf. Series: Materials Science and Engineering 973 (2020) 012003 doi:10.1088/1757-899X/973/1/012003 Validation of a simplified model for liquid propellant rocket engine combustion chamber design M Hegazy1, H Belal2, A Makled3 and M A Al-Sanabawy4 1 M.Sc. Student, Rocket Department, Military Technical College, Egypt 2 Assistant Professor, Rocket Department, Military Technical College, Egypt 3 Associate Professor. Zagazig University, Egypt 4 Associate Professor. Rocket Department, Military Technical College, Egypt [email protected] Abstract. The combustion phenomena inside the thrust chamber of the liquid propellant rocket engine are very complicated because of different paths for elementary processes. In this paper, the characteristic length (L*) approach for the combustion chamber design will be discussed compared to the effective length (Leff) approach. First, both methods are introduced then applied for real LPRE. The effective length methodology is introduced starting from the basic model until developing the empirical equations that may be used in the design process. The classical procedure of L* was found to over-estimate the required cylindrical length in addition to the inherent shortcoming of not giving insight where to move to enhance the design.