Combustion Tap-Off Cycle

Total Page:16

File Type:pdf, Size:1020Kb

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. The most unique aspect of this cycle is that it allows for the engine to go into “idle mode” with a much lower thrust than maximum. The wide range of thrust options allows for this cycle to be throttled, which is very appealing for rockets designed to carry people. This report will discuss the two applications of the combustion tap-off cycle, the J-2S and BE-3. J-2S is a technology demonstrator and has never been flown before, but has been tested extensively. BE-3 has been tested and flown a number of times and promises to fly the first space tourists by 2018. 2 2.0 J-2S The first combustion tap-off cycle engine made was the J-2S which was developed between 1965 and 1969. This engine was developed by heritage Rocketdyne and although it was never used in flight, it was tested extensively. NASA considered using the engine for many future projects due to its throttling capability, but it was never flown. The J-2S was designed as a part of the J-2 series which was designed as a replacement for the upper stages of the Saturn vehicle. The S stands for simplified as the J-2S was an upgraded and simplified version of the J-2X (experimental) engine. The J-2S program tested six different flight configurations in sea level, high-altitude, and vacuum conditions. Over the course of 273 tests, the engine gained 30,858 seconds of operational experience. The most unique part of the J-2S engine was the Idle Mode feature. This feature allowed the engine to operate at low thrusts for a period of time. In Idle Mode, the engine had a nominal thrust of 5,000 pound-force and a mixture ratio of 2.5, relative to the main-stage operation with a thrust between 230,000 and 256,000 pound-force and a mixture ratio of 5.5. A basic schematic of the J- 2S engine can be seen below in Figure 2.1. Figure 2.1: J-2S Basic Engine Schematic The tap-off cycle can be seen in the figure above as some of the hot gases are channeled from the edges of the combustion chamber and into a fuel turbopump. The gases power the turbopump and then are expelled as exhaust. With the tap-off cycle, this engine has an Isp of 436. 3 3.0 BE-3 BE-3 (Blue Engine-3) is the first combustion tap-off cycle engine ever to have flown on a rocket. It was developed by Blue Origin and first announced in 2013. The engine was designed to fly on their New Shepard vehicle which will bring up to six astronauts at a time to altitudes over 100 kilometers. Like J-2S, BE-3 operates on liquid hydrogen and liquid oxygen. However, it only provides 110,000 pounds of thrust and can throttle down to 20,000 pounds which allows it to make vertical landings and be reused multiple times. Even though this engine does not have as large of a range of operational thrusts as the J-2S, it works well for the rocket that it has been designed for. Figure 3.1 below shows a test firing of the BE-3 engine from afar at Blue Origin’s test facility in West Texas. Figure 3.1: BE-3 Engine Test Firing The figure above does not show much of the engine, which is due to Blue Origin’s tendency to be secretive about their work. Not much information is available to the public regarding the performance of the engine. All that is known regarding the Isp is that it is “relatively high” as a result of using the combustion tap-off cycle. The tap-off cycle is a unique one for Blue Origin to choose for its reusable rockets as the cycle had only been built and tested once before with the J-2S engine. Blue Origin states that the cycle is suited for human spaceflight as it has a single combustion chamber and a “graceful” shutdown 4 mode. The single combustion chamber allows for the system to be simpler and therefore less likely to experience a failure. The graceful shutdown mode stems from the throttling capabilities of the tap-off cycle. Even though the tap-off cycle works for BE-3, the engine does not come without its challenges. The tap-off cycle has a complex start-up system and high temperature turbine gases that drive the combustion process which makes the system a little more complicated. The nature of the cycle also causes it to tend to shut down rather than continue the combustion process. This is due to the fact that it only has one combustor and no pre-burners which is different from many other engine cycles. Blue Origin is also developing modifications to the BE-3 engine that can be used for an upper stage engine called the BE-3U. A shorter nozzle works well for deep throttling and landing while a large expansion ratio nozzle works well at higher altitudes. These modifications will allow for the engine to be used on the upper stages of rockets for ULA or other contractors. 5 4.0 CONCLUSION The J-2S and BE-3 are both successful examples of the combustion tap-off cycle. The cycle was proven to be both viable and useful by the J-2S which paved the way for BE-3. Even though J-2S never flew, it showed that the tap-off cycle was useful for its throttling capabilities and had a relatively high Isp. The BE-3 engine proved that the cycle could be successfully flown on a rocket, carry people comfortably, and land safely after flight. 6 5.0 REFERENCES J-2 Engine Fact Sheet (1968). In Marshall Space Flight Center. Retrieved December 6, 2016, from https://www.nasa.gov/centers/marshall/pdf/499245main_J2_Engine_fs.pdf Norris, G. (2013, December 3). Blue Origin Demos New Shepard Mission Engine Cycle. In Aviation Week Network. Retrieved December 6, 2016, from http://aviationweek.com/space/blue-origin-demos-new-shepard-mission-engine-cycle Our Approach to Technology (2016). In Blue Origin. Retrieved December 6, 2016, from https://www.blueorigin.com/technology Pillow, C. E. (1970, September). Altitude Developmental Testing of the J-2s Rocket Engine. In Defense Technical Information Center. Retrieved December 6, 2016, from http://www.dtic.mil/dtic/tr/fulltext/u2/874400.pdf Wade, M. (2016). J-2S. In Encyclopedia Astronautica. Retrieved December 6, 2016, from http://www.astronautix.com/j/j-2s.html 7 .
Recommended publications
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • Cryogenic Technology & Rocket Engines
    ISSN (O): 2393-8609 International Journal of Aerospace and Mechanical Engineering Volume 2 – No.5, August 2015 Cryogenic Technology & Rocket Engines AKHIL GARG KARTIK JAKHU KISHAN SINGH ABHINAV B.Tech – Aerospace B.Tech – Aerospace B.Tech – Aerospace MAURYA Engg. Engg. Engg. B.Tech – Aerospace PUNJAB PUNJAB PUNJAB Engg. TECHNICAL TECHNICAL TECHNICAL PUNJAB UNIVERSITY, UNIVERSITY, UNIVERSITY, TECHNICAL JALANDHAR JALANDHAR JALANDHAR UNIVERSITY, akhilgarg.313@g kartik.lphawk@g kishansngh1996 JALANDHAR mail.com mail.com @gmail.com abhinavguru123 @gmail.com ABSTRACT 3.2 What is Cryogenic Rocket Engine? This paper is all about the rocket engine involving the use of A cryogenic rocket engine is a rocket engine that cryogenic technology at a cryogenic temperature (123K). This uses a cryogenic fuel or oxidizer, that is, its fuel or basically uses the liquid oxygen and liquid hydrogen as an oxidizer (or both) is gases liquefied and stored at oxidizer and fuel, which are very clean and non-pollutant very low temperatures. Notably, these engines were fuels compared to other hydrocarbon fuels like petrol, diesel, one of the main factors of the ultimate success in gasoline, LPG, CNG, etc., sometimes, liquid nitrogen is also reaching the Moon by the Saturn V rocket. used as an fuel. During World War II, when powerful rocket engines were first considered by the German, American and Keywords Soviet engineers independently, all discovered that Rocket engine, Cryogenic technology, Cryogenic temperature, rocket engines need high mass flow rate of both Liquid hydrogen and Oxygen. oxidizer and fuel to generate a sufficient thrust. At that time oxygen and low molecular weight 1.
    [Show full text]
  • Sidney Allan Ceng, Fraes 1909-1973
    frustration caused him to tend to withdraw somewhat broader front. This made him very vulnerable and it was from the company of others and thus give an appearance in this respect that his wife (Tommy) was such a tower of of aloofness. Those of us who were privileged to know strength to him throughout their long married life. Her him better recognised this as mere illusion for he could be death just over three years ago was a great blow to him. the most warm and charming of companions. His very Though now gone he will live on for as long as people keen sense of humour could always be relied upon to en­ are concerned with the problems of flight in a way that is liven any conversation and often even shone through much aptly described by words that Barry himself used of of his technical writing, whilst in the right circumstance he another, could use a caustic wit with quite devastating effect Above all he loved the simple things of life—the beauty of nature "He is not dead. Still on my mortal breath and the countryside. Walking was a favourite pastime of Swells a low music from his heart's desire. his as was also working in his garden and it is not un­ I am most proud, and you most cheated, Death, natural that this part of him is reflected so well in a num­ Knowing in bis closed book this deathless fire". ber of his poems. A man of great sensitivity he always Poems, 1925 reacted vigorously to any suggestion of man's inhumanity to man whether on a person to person level or on a H.
    [Show full text]
  • Solid Propellant Rocket Engines - V.M
    THERMAL TO MECHANICAL ENERGY CONVERSION: ENGINES AND REQUIREMENTS – Vol. II - Solid Propellant Rocket Engines - V.M. Polyaev and V.A. Burkaltsev SOLID PROPELLANT ROCKET ENGINES V.M. Polyaev and V.A. Burkaltsev Department of Rocket engines, Bauman Moscow State Technical University, Russia. Keywords: Combustion chamber, solid propellant load, pressure, temperature, nozzle, thrust, control, ignition, cartridge, aspect ratio, regime. Contents 1. Introduction 2. Historical information 3. SPRE scheme and main units 4. SPRE operation 5. Parameter optimization, the approach and results 6. Transient regime 7. Service 8. Development prospects 9. Conclusions Acknowledgments Glossary Bibliography Biographical Sketches 1. Introduction Solid propellant rocket engines (SPRE) are called the direct reaction engines, in which chemical energy of the solid propellant being placed in the combustion chamber is transformed at first to thermal energy, and then to kinetic energy of the combustion products thrown away with high velocity in the environment. The momentum of combustion products discharging through the nozzle is equal to the impulse of reactive force being created by the engine. 2. Historical information First of rocketsUNESCO known to us were rockets – with EOLSS primitive powder rocket engines used in China near 5000 years ago for pleasure and military aims (so-called "fiery arrows", Figure 1). SAMPLE CHAPTERS The first rocket propellant was black smoky powder (potassium saltpetre with charcoal mixture). In Russia, powder rockets appeared in the beginning of XVII century. In 1680, Tsar Peter I founded "rocket institution" in Moscow for firework rockets making. In 1717 lighting signal rockets existed for 200 years without changes. In the beginning of XIX century, Englishman Kongrev improved the "fiery arrows" having been borrowed from Hindus.
    [Show full text]
  • Space Shuttle Main Engine Orientation
    BC98-04 Space Transportation System Training Data Space Shuttle Main Engine Orientation June 1998 Use this data for training purposes only Rocketdyne Propulsion & Power BOEING PROPRIETARY FORWARD This manual is the supporting handout material to a lecture presentation on the Space Shuttle Main Engine called the Abbreviated SSME Orientation Course. This course is a technically oriented discussion of the SSME, designed for personnel at any level who support SSME activities directly or indirectly. This manual is updated and improved as necessary by Betty McLaughlin. To request copies, or obtain information on classes, call Lori Circle at Rocketdyne (818) 586-2213 BOEING PROPRIETARY 1684-1a.ppt i BOEING PROPRIETARY TABLE OF CONTENT Acronyms and Abbreviations............................. v Low-Pressure Fuel Turbopump............................ 56 Shuttle Propulsion System................................. 2 HPOTP Pump Section............................................ 60 SSME Introduction............................................... 4 HPOTP Turbine Section......................................... 62 SSME Highlights................................................... 6 HPOTP Shaft Seals................................................. 64 Gimbal Bearing.................................................... 10 HPFTP Pump Section............................................ 68 Flexible Joints...................................................... 14 HPFTP Turbine Section......................................... 70 Powerhead...........................................................
    [Show full text]
  • Apollo Rocket Propulsion Development
    REMEMBERING THE GIANTS APOLLO ROCKET PROPULSION DEVELOPMENT Editors: Steven C. Fisher Shamim A. Rahman John C. Stennis Space Center The NASA History Series National Aeronautics and Space Administration NASA History Division Office of External Relations Washington, DC December 2009 NASA SP-2009-4545 Library of Congress Cataloging-in-Publication Data Remembering the Giants: Apollo Rocket Propulsion Development / editors, Steven C. Fisher, Shamim A. Rahman. p. cm. -- (The NASA history series) Papers from a lecture series held April 25, 2006 at the John C. Stennis Space Center. Includes bibliographical references. 1. Saturn Project (U.S.)--Congresses. 2. Saturn launch vehicles--Congresses. 3. Project Apollo (U.S.)--Congresses. 4. Rocketry--Research--United States--History--20th century-- Congresses. I. Fisher, Steven C., 1949- II. Rahman, Shamim A., 1963- TL781.5.S3R46 2009 629.47’52--dc22 2009054178 Table of Contents Foreword ...............................................................................................................................7 Acknowledgments .................................................................................................................9 Welcome Remarks Richard Gilbrech ..........................................................................................................11 Steve Fisher ...................................................................................................................13 Chapter One - Robert Biggs, Rocketdyne - F-1 Saturn V First Stage Engine .......................15
    [Show full text]
  • Lesson 2: YOU're LAUNCHING a ROCKET!
    Adventures in Aerospace: Lesson 2 Volunteer’s Guide Key to Curriculum Formatting: ► Volunteer Directions ■ Volunteer Notes ♦ Volunteer-led Classroom Experiments Lesson 2: YOU’RE LAUNCHING A ROCKET! ► Begin the presentation by telling the class that this is “Lesson 2: You’re Launching a Rocket!” If this is your second visit, reintroduce yourself and the program. Briefly review key concepts from the first lesson, “You’re Piloting a Plane!” If this is your first visit, here is a suggested personal introduction: “Hello, my name is _____________, and I am a _________________ (position title) at Aerojet. I or another Aerojet volunteer will be visiting your class once over the next few months to speak to you about space exploration and space travel. We will learn about the basics of aerodynamics, rocket propulsion, and spaceflight to the space station, the moon, and future missions to Mars!” ► Answer any questions left over from the previous visit. MATERIALS NEEDED • AiA Multimedia Presentation (AMP) • DVD-ROM Page 1 of 11 Adventures in Aerospace: Lesson 2 Volunteer’s Guide • TV or projection screen • Handouts • Index cards ► See lesson to assess total equipment needs. LESSON OUTLINE Introduction Lesson Concepts Vocabulary Rockets vs. Airplanes Newton’s Laws • First Law • Second Law • Third Law What Type of Rocket Are You Launching? • Types of Engines Comparing and Contrasting Liquid Engines and Solid Motors Other Types of Rocket Engines Applying What We’ve Learned Experiment INTRODUCTION Rocket launches have mesmerized audiences, often entire nations, for centuries. What kind of power does it take to propel spacecraft out of the atmosphere and into the vacuum of space? This unit introduces you to rocket propulsion systems.
    [Show full text]
  • Design and Dynamic Characteristics of a Liquid-Propellant Thrust Chamber
    DESIGN AND DYNAMIC CHARACTERISTICS OF A LIQUID-PROPELLANT THRUST CHAMBER Avandelino Santana Junior Instituto de Aeronáutica e Espaço, Centro Técnico Aeroespacial, IAE/CTA, CEP 12228-904 - São José dos Campos, SP, Brasil. E-mail: [email protected] Luiz Carlos Sandoval Góes Instituto Tecnológico de Aeronáutica, ITA, CEP 12228-900 - São José dos Campos, SP, Brasil. E-mail: [email protected] Abstract. According to the national program for space activities (PNAE), which is elaborated by the Brazilian space agency (AEB), the liquid propulsion technology is essential in the de- velopment of the next launch vehicle, called VLS-2. The advantages of liquid-propellant rocket engines are their high performance compared to any other conventional chemical en- gine and their controllability in terms of thrust modulation. Undeniably, the most important component of these engines is the thrust chamber, which generates thrust by providing a vol- ume for combustion and converting thermal energy to kinetic energy. This paper presents the design and the dynamic analysis of a thrust chamber, which can be part of the future Brazil- ian rocket. The basic components of the thrust chamber assembly are described, a mathe- matical model for simulation of the system at nominal regime of operation is constructed, and the dynamic characteristics including the stability analysis are briefly discussed. Keywords: Liquid rocket engine, liquid propulsion, rocket engine design, dynamic modeling, dynamic analysis. 1. INTRODUCTION The design of an engine and its components is not a simple task, especially concerning liquid-propellant engine system, because it includes complex and multidisciplinary problems. Since rocket engines are airborne devices, a desirable thrust chamber combines lightweight construction with high performance, simplicity, and reliability (Sutton, 1986).
    [Show full text]
  • Liquid Propollant Rocket Engines
    THERMAL TO MECHANICAL ENERGY CONVERSION: ENGINES AND REQUIREMENTS – Vol. II - Liquid Propellant Rocket Engines - V.M. Polyaev and V.A. Burkaltsev LIQUID PROPELLANT ROCKET ENGINES V.M. Polyaev and V.A. Burkaltsev Department of Rocket engines, Bauman Moscow State Technical University, Russia. Keywords: Liquid rocket engine, liquid rocket propellant, chamber, combustion products, pressure, temperature, density, cooling, supply system, turbopump assembly, gas generator, engine installation, thrust, specific impulse, specific mass. Contents 1. Introduction 2. LRE general information 3. Main LRE parameters 4. LRE structure and liquid rocket engine installations (LREI) schemes 5. Historical reference 6. LRE development tendencies 7. Conclusions Acknowledgment Glossary Bibliography Biographical Sketches 1. Introduction All chemical rocket engines have two common characteristics. They utilize chemical reactions in a thrust chamber to produce a high-pressure, high-temperature gas at the entrance to a converging-diverging exhaust nozzle. The hot propellant gas expands in flowing through the nozzle, and the expansion process converts a portion of the thermal energy released by the chemical reaction into kinetic energy associated with a high- velocity gaseous-exhaust jet. 2. LRE general information The liquid propellant rocket engine (LRE) is a direct reaction engine using the liquid rocket propellantUNESCO stored on a flight vehicle – board EOLSS for thrust creation. The liquid rocket propellant (LRP) is a substance in the liquid state which is capable to be converted intoSAMPLE a reactive gas jet discharging CHAPTERS from the engine and creating a thrust as a result of the exothermal reaction associated with heat release. LRP consists of liquid components. The propellant components can include one substance or a mixture of individual chemical substances.
    [Show full text]