Aircraft hydraulic power system design for low temperature

Low temperature is an unwanted working environment for aircraft hydraulic power system. In order to working normally, a warm up system and process should be considered during aircraft design. This study introduced the warm up requirements and process of typical aircraft. Then the warming characteristics are analysed by simulation. The results indicate that the warm process with EMP and EDP can make the hydraulic aircraft system reach the full performance temperature in required time. Increase the working pressure can even speed this process. The effect on pump suction under low temperature is also analysed. In the last, a new warm up method with warming valve is introduced. These methods can be used in aircraft hydraulic design for low temperature.