空水共用涡轮机气动设计与数值仿真

跨介质航行器是一种具备远程快速打击、重复出入水以及高效突防能力的新概念航行器，而其中涡轮发动机在跨介质航行器不同航行阶段的工作参数差别很大。为解决水下、空中及起飞工况下的空水共用涡轮机的气动设计，结合损失模型的方法提出一种空水共用涡轮机设计方法，通过数值仿真方法验证气动设计方法的合理性以及起飞工况的可行性。研究结果表明：在不同工况下，数值仿真结果与一维气动设计结果的相对误差均在2%以内；使用数值损失分解方法进一步分析了涡轮机的各部分损失，发现叶型损失为空水共用涡轮机的主要损失；水下工况时流场内存在激波和分离涡，部分进气度很小，损失较大；空中工况则流动更为均匀，损失较小；起飞工况时涡轮机工作在非设计点，此时主要依靠水下喷管做功，空中喷管则会产生负功率。该方法可为空水共用涡轮机的优化设计和试验提供参考。

Aerodynamic Design and Numerical Simulation of Air-water Shared Turbines

Trans-media vehicles are an innovative aircraft with long-range rapid striking, repeated entry, and efficient penetration capabilities. However, the turbine working parameters of trans-media vehicles at different stages differ significantly. To realize the aerodynamic design of shared turbines for underwater, in-flight, and takeoff conditions, loss model is integrated to come up with an air-water shared turbine design. Numerical method is used to verify the accuracy of mean-line design method and the feasibility of takeoff conditions. The results show that the relative error between the numerical results and mean-line design results is within 2% under various working conditions. The numerical loss breakdown method is then used to further analyze the turbine losses and reveal that profile loss is the main loss of the air-water shared turbine. The shock waves and separation vortices are found in the passage under underwater conditions. In addition, the partial admission ratio is also very low, resulting in a relatively high loss. During flight, the flow is more uniform and hence the loss is smaller. During takeoff, the turbine works at an off-design point. The output power relies on the underwater nozzle, while air nozzle generates negative power. This study can provide a reference for the optimal design and experiment of air-water shared turbines.