Preliminary Design And Experimental Analysis Of Combustion Chamber For Micro-turbojet Engine

Micro-turbojet engine is one of the most common power devices in the micro air vehicle,and combustion chamber is one of the most important components of the micro-turbojet engine.It is the most important direction of research and development of the micro-turbojet.Based on the combustion chamber design method of the large and medium sized turbojet engine,this paper mainly studies the design method for the combustion of micro-turbojet engine according to the working principle of micro-turbojet engine.Meanwhile,a combustion chamber design program for the micro-turbojet has been developed.The thermodynamic design and structural design of a micro-turbojet engine are completed by using the design software,and the comprehensive combustion performance of the engine was measured and analyzed.Firstly,according to the preliminary design method of the large and medium-sized turbojet engine combustor and the characteristics of the micro-turbojet engine,the preliminary design method for micro-turbojet combustion chamber was studied,including the preliminary design of the combustion chamber size,the distribution of air flow and the combustion chamber aerodynamic heat calculation.Then,based on the preliminary design method of the micro-turbojet combustion chamber,a micro-turbojet combustion chamber preliminary design software was developed using Visual C#language.The software can be used to determine the basic size of the micro-turbojet combustion chamber and calculate the aerodynamic and thermal parameters in the inner and outer annular chambers and the flame tube,and can graphically visualize the calculated results and save the data records.The software interface is friendly,and the user operation is convenient.Then,the design of the micro-turbojet engine combustion chamber was completed by the preliminary design software of the micro-turbojet engine,and the micro-turbojet engine was tested for its combustion performance.The parameters such as fuel air flow rate,rotational speed,wall and gas temperature,combustion products,pressure and other parameters during the operation of the micro-turbojet engine were measured to analyze the performance of the modified micro-turbojet engine.Finally,the diversity of the working fuel of the micro-turbojet engine was discussed,and the combustion performance of the engine with the renewable energy-alcohol as fuel was experimentally analyzed.It is found that the use of alcohol can maintain the stability of the engine work,but the combustion performance needs to be further improved.The combustion chamber needs to be further optimized for the fuel.In this paper,the preliminary design method of micro-turbojet combustor is discussed and practiced.The combustion performance of micro-turbojet after combustion chamber modification is measured experimentally.The advantages and disadvantages of the utilization of renewable energy and the possible improvement direction are discussed.The above research work has made a useful contribution to the further development of micro-turbojet in the Application of Miniature Whirlpools in Emerging Weapons and Equipment such as intelligent ammunition,and the design technology of micro-turbojet.This is the follow-up to explore the development.