基于直升机飞行性能需求的涡轴发动机设计参数选取方法研究

以直升机性能计算方法为基础，辅以考虑尺寸效应及设计能力的涡轴发动机设计方法，建立了以直升机旋翼桨盘载荷及最大起飞功重比为特征参数的直升机/涡轴发动机性能约束分析模型、任务分析模型及基于直升机飞行性能需求的涡轴发动机设计参数选取模型。针对涡轴发动机部件/系统设计能力及直升机飞行性能需求，首先开展了给定涡轴发动机循环参数下的流量匹配计算，然后开展了涡轴发动机循环参数选取研究。研究表明，所建立的直升机/涡轴发动机性能约束分析模型、任务分析模型可实现给定飞行任务的直升机/涡轴发动机性能耦合设计；在给定涡轴发动机循环参数条件，由于尺寸效应，涡轴发动机部件效率受进口流量的影响，其设计点功率并不随流量等比例变化，从而使得直升机起飞总重呈现非等比例变化；在涡轴发动机循环参数选择时，在满足直升机飞行性能需求下，存在涡轴发动机耗油率与单位功率之间权衡下的循环参数选取，使得直升机起飞总重最小。

Selection Method of Turboshaft Engine Design Parameters Based on Helicopter Flight Performance Requirements

Based on the calculation method of helicopter performance and the design method of turboshaft engine considering size effect and design capability, the constraint analysis model, task analysis model and design parameter selection model of helicopter / turboshaft engine based on helicopter rotor disc load and maximum takeoff power weight ratio are established. In view of the design capability of turboshaft engine components / systems and helicopter flight performance requirements, the flow matching calculation under given turboshaft engine cycle parameters is carried out, and then the selection of turboshaft engine cycle parameters is studied. The results show that the established helicopter / turboshaft engine performance constraint analysis model and task analysis model can realize the helicopter / turboshaft engine performance coupling design for given flight mission; under the condition of given turboshaft engine cycle parameters, the efficiency of turboshaft engine components is affected by inlet flow due to size effect, the power at design point does not change proportionally with flow rate, and the total weight of helicopter takeoff presents non-proportional change. In the selection of turboshaft engine cycle parameters, there is a balance between turboshaft engine fuel consumption and unit power to minimize the total takeoff weight for meeting helicopter flight performance requirements.