中冷压降对多级增压航空活塞发动机性能影响研究

Effects of intercooler pressure drop on performance of multistage turbocharged aviation piston engine

关键词:  航空活塞发动机  多级中冷  多级增压  压降  发动机性能

Key words:  Aviation piston engine  Multiple-stage intercooling  Multiple-stage supercharging  Pressure drop  Engine performance

摘要:

为了提高航空用活塞发动机升限和高空性能，本文基于仿真方法，建立带有三级增压中冷的复合增压系统GT-POWER计算模型，并研究了不同飞行高度下各级中冷器的压降对增压系统及发动机性能参数的影响。研究表明，级后中冷器的压降会改变不同飞行高度下的增压系统中涡轮增压器的效率及实际总压比，进而影响发动机的动力性能和燃油经济性。其中，低压级中冷器的压降影响最为显著。在海拔20 km，当中冷器压降增大至6 kPa时，低压级中冷压降导致增压系统实际总压比下降了28.9%。同时，低压级中冷压降造成的航空活塞发动机功率损失约是同工况高压级造成的4倍、机械级的8.3倍。

Abstract:

To enhance the practical ceiling and high altitude dynamic performance of aviation piston engines， this study investigates the effects of pressure drop caused by different stages of intercoolers on the performance parameters of the turbocharger system and the engine under various flight altitudes based on simulation methods using a GT-POWER model for a three-stage supercharged engine. The results demonstrate that intercooler pressure drop significantly influences the turbocharger efficiency and the real total pressure ratio in the supercharging system under various flight altitudes， consequently impacting the engine power and fuel efficiency. The pressure drop in the low-pressure-stage intercooler exhibits the most pronounced influence. At an altitude of 20 km， a 6 kPa of pressure drop in the intercooler leads to a 28.9% decrease in the real total pressure ratio for the low-pressure-stage intercooler. Furthermore， under the same conditions， the engine power loss caused by the intercooler pressure drop in the low-pressure stage is approximately 3 times greater than that in the high-pressure stage and 7.3 times greater than that in the mechanical stage.