直升机动力舱冷却系统冷却孔进气优化设计

对某型民用直升机动力舱冷却系统冷却孔的进气性能开展优化研究,参考飞机辅助动力单元(Applicant power unit,APU)进气系统形式设计了两类收风装置。采用数值仿真手段,对比分析在多个速度的前飞状态和不同爬升率的爬升状态下3处冷却孔的进气性能。结果显示基于Scoop型设计的收风装置在直升机大速度前飞状态收风效果最好,但在小速度前飞状态进气性能没有得到改善。基于Flush型设计的收风装置同样具有改善进气性能的作用,其最显著优点是在所有飞行状态均保证较高的冷却进气量。为后续的优化设计研究工作指明了方向。

Optimal Design on Aerodynamic Performance of Cooling Hole Intakes in Engine Bay Cooling System of Helicopter

For one type of civil helicopter, optimal design on aerodynamic performance of cooling hole intakes in the engine bay cooling system is studied. Two kinds of air collecting device are designed referring to applicant power unit (APU) intake system. The aerodynamic performance of the three cooling hole intakes in the condition of forward flight with various velocities and climb flight with different climbing rates are analyzed using numerical simulation method. The results show that the air collecting device designed according to scoop type has the best air collecting effect when the helicopter is flying forward at a high speed. Meanwhile, there is no improvement on aerodynamic performance of cooling hole intakes when helicopter is flying forward at a low speed. The air collecting device based on flush type also has a good function of improving air intake performance. And the most obvious advantage is to ensure a high cooling air flow in all flight conditions. Reasonably, it seems that the air collecting device designed based on flush type is more suitable for helicopter, which well points out the direction of the subsequent optimal design research.