摘要
This paper presents a method of thermal state calculation of combustion chamber in small thrust liquid rocket engine. The goal is to predict the thermal state of chamber wall by using basic parameters of engine: thrust level, propellants, chamber pressure, injection pattern, film cooling parameters, material of wall and their coating, etc. The difficulties in modeling the startup and shutdown processes of thrusters lie in the fact that there are the conjugated physical processes occurring at various parameters for non-design conditions. A mathematical model to predict the thermal state of the combustion chamber for different engine operation modes is developed. To simulate the startup and shutdown processes, a quasi-steady approach is applied by replacing the transient process with time-variant operating parameters of steady-state processes. The mathematical model is based on several principles and data commonly used for heat transfer modeling: geometry of flow part, gas dynamics of flow, thermodynamics of propellants and combustion spices, convective and radiation heat flows, conjugated heat transfer between hot gas and wall, and transient approach for calculation of thermal state of construction. Calculations of the thermal state of the combustion chamber in single-turn-on mode show good convergence with the experimental results. The results of pulsed modes indicate a large temperature gradient on the internal wall surface of the chamber between pulses and the thermal state of the wall strongly depends on the pulse duration and the interval.
This paper presents a method of thermal state calculation of combustion chamber in small thrust liquid rocket engine. The goal is to predict the thermal state of chamber wall by using basic parameters of engine: thrust level, propellants, chamber pressure, injection pattern, film cooling parameters, material of wall and their coating, etc. The difficulties in modeling the startup and shutdown processes of thrusters lie in the fact that there are the conjugated physical processes occurring at various parameters for non-design conditions. A mathematical model to predict the thermal state of the combustion chamber for different engine operation modes is developed. To simulate the startup and shutdown processes, a quasi-steady approach is applied by replacing the transient process with time-variant operating parameters of steady-state processes. The mathematical model is based on several principles and data commonly used for heat transfer modeling: geometry of flow part, gas dynamics of flow, thermodynamics of propellants and combustion spices, convective and radiation heat flows, conjugated heat transfer between hot gas and wall, and transient approach for calculation of thermal state of construction. Calculations of the thermal state of the combustion chamber in single-turn-on mode show good convergence with the experimental results. The results of pulsed modes indicate a large temperature gradient on the internal wall surface of the chamber between pulses and the thermal state of the wall strongly depends on the pulse duration and the interval.
引文
1.Kokorin VV,Rutovskiy NB,Solov’yev EV.Complex optimization of propulsion systes’control system.Moscow:Mechanical Engineering;1983.p.184.
2.Lee KH,Lee SR.Comparative study of lunar mission requirements and onboard propulsion system performance.Prog Aerosp Sci 2011;47(6):480-93.
3.Ohminami K,Ogawa H,Uesugi K.Numerical bipropellant thruster simulation with hydrazine and NTO reduced kinetic reaction model.47th AIAA aerospace sciences meeting including the new horizons forum and aerospace exposition;2009 Jan 5-8Orlando,Florida,USA.Reston:AIAA;2009.p.452.
4.Ohminami K,Sawai S,Uesugi K,Yamanish N,Koshi MHydrazine and di-nitrogen tetroxide combustion model inside film-cooled bipropellant thruster.45th AIAA/ASME/SAE/ASEEjoint propulsion conference&exhibit;2009 Aug 2-5;Denver Colorado,USA.Reston:AIAA/ASME/SAE/ASEE;2009.p5044.
5.Rutovskiy NB.Copmplex investigation of parametrs of liquid rocket engine of small thrust using in control system of space vechicle[dissertation].Moscow:Moscow Aviation Institute1973.
6.Gladkova NV.Development of a mathematical model of lowthrust liquid-fuel rocket engines operating in the pulsed mode[dissertation].Moscow:Moscow Aviation Institute;1980.
7.Vorojeeva OA,Yagodnikov DA.Numerical study of the operating condition effect on the thermal state of the structure of low thruster on oxygen-methane propellant operating in pulsed model Eng J:Sci Innov 2017;1:1-11.
8.Vorojeeva OA,Yagodnikov DA.Mathematical model and computational research of combustion chamber wall thermal state for gaseous-propellant oxygen-methane low-thrust rocket engine on a pulse mode.Proc Higher Educ Inst 2013;7:11-20.
9.Purohit G,Donatelli P,Ellison J,Dhir V,Purohit G,Donatelli Pet al.Transient thermal model of a film-cooled bipropellant thruster.38th aerospace sciences meeting and exhibit;2000Jan 10-13;Reno,USA.Reston:AIAA;2000.p.1072.
10.Purohit G,Donatelli P,Ellison J,Dhir V.Parametric examination of propellant temperature and pressure effects on transient thermal response of a radiation-cooled bipropellant thruster.38th aerospace sciences meeting and exhibit;2000 Jan 10-13;Reno,USA.Reston:AIAA;2000.p.1072.
11.Vorob’yev AG.Experimental-theoretical model of the thermal state of the combustion chamber of two-component liquid rocket engines of small thrust operating in a continuous mode[dissertation].Moscow:Moscow Aviation Institute;2010.
12.Vorob’yev AG.Mathematical model of thermal state of LREST.Moscow:MAI Publ;2007.p.42-9.
13.Berezanskaya EL,Kurpatenkov AD,Nadezhdina YD.Calculation of convective heat flow in laval nozzle.Moscow:MAI Publ;1976.p.77.
14.Vasil’yev AP,Kudryavtsev VM,Kuznetsov VA.The basic of theory and calculation of LRE.Moscow:Vysshaja Shkola Publ;1975.p.656.
15.Kuz’min MP,Lagun IM.Nonstationary heat state of engine’s elements of flying vechicle.Moscow:Mechanical Engineering;1988.p.240.
16.Egorychev VS,Sulinov AV.Liquid rocket engine of small thrust and their performance.Samara:SGAU Publ;2010.p.103.
17.GOST 17655-89.Liquid rocket engine.Term and definition.59.
18.GOST 22396-77.Liquid rocket engine of small thrust.Term and definition.17.
19.Bezmenova NV.Numerical modeling of conjugate heat transfer in LRE of small thrust for performance improve.Samara:SGAUPubl;2001.p.176.
20.Aerojet Rocketdyne.Bipropellant rocket engines.[Internet].[cited2017 June 18].Available from:http://www.rocket.com/propulsion-systems/bipropellant-rockets.
21.AMBR engine for science missions.[Internet].[cited 2017 June 18].Available from:http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.../20090001339.pdf.
22.Northrop Grumman.Bipropellant engines&thrusters.[Internet].[cited 2017 June 18].Available from:http://www.northropgrumman.com/Capabilities//Propulsion Productsand Services/Pages//Bipropellant Engines And Thrusters.aspx.
