Thermodynamic Characteristic Study Of Bellow-Type High Temperayure Flow Rate Control Valve

The real-time and accurate control of the fuel is the key technique for the working performance of the Scramjet engine. It is of great significance to the enhancement of Scramjet efficiency and working mode. The total temperature of Scramjet engine is raised up when it works. Therefore the active cooling method is necessary for scramjet engines, which means that, before going into the combustion chamber, the fuel circulates across the engine surface as coolant. Hence the temperature of fuel becomes as high as 500~600°C. The performance of the flow rate control valve which works at high temperature is important for the performance of the Scramjet. Therefore, in order to guarantee the performance of the Scramjet, a bellow-type high-temperature control valve is developed in this paper.The bellow-type high-temperature control valve has the good seal characteristic due to the bellow, which separates the guide type control system and the fuel supply system which is controled, and the accurate flow control characteristic could be obtained in high-temperature environment due to the cone valve structure. To make out the effect of high temperature to the bellow-type high-temperature control valve, the thermal-dynamic characteristics of the control valve at high temperature are analyzed in this paper. The heat transfer and thermal stress and strain models are built. The finite element numerical computing methods of the thermal-dynamic characteristics are studied also. The analysis model of the valve is built by the finite element software. The thermodynamic characteristics of the control valve are studied under different working conditions, when the valve is made of different materials. The steady-state temperature field, transient temperature field, thermal stress field and thermal strain field are calculated and the results are presented in this paper. Also the temperatures at certain points are measured which provide a verification of the results of the calculation. After a comprehensive analysis the thermal-dynamic characteristics of the control valve are presented which provide a theoretic basis for the design and improvement of the structure and the choice of the material of the valve.