动力涡轮复合柴油机性能的数值研究

Numerical study of power turbine compound engine performance

动力涡轮作为一种新型内燃机余热能回收装置,可以起到节能减排的作用。本文综合旁通补燃、顺序涡轮增压和两级涡轮增压的工作原理,将动力涡轮、涡轮增压器以及旁通补燃室相结合,这种复合柴油机增压系统可以较好地对排气能量进行利用。本文分别针对动力涡轮与增压器涡轮串联和并联两种复合形式,利用GT-POWER软件建立涡轮复合柴油机仿真模型,研究串并两种方案的性能。研究表明,在并联模型中,动力涡轮输出功率存在最佳流量比0.31时总输出功率最大;在串联模型中,动力涡轮输出功率存在最佳功率比0.43时总输出功率最大;从整体上看,串联方案比并联方案有优势,可以大大提高总输出功率,更多地回收废气能量。

As a new energy recovery device, power turbine plays a role in energy conservation. Integrating the principles of bypass and complementary combustion, sequential turbo-charging system and twin-supercharging system, the compound engine supercharging system which was made up with the power turbine, turbocharger and bypass afterburner can better utilize the exhaust gas energy. The power turbine and turbocharger turbine series program and parallel program were elaborated. Turbo compound engine simulation model was established with the GT-POWER software to study the performance of the two programs. The total output power will reach maximum when optimal flow ratio value is 0.31 in the parallel model and optimal power ratio value is 0.4 in the series model. Overall, the series program has advantages over parallel program, which could increase the total output power greatly and recover more exhaust energy.