Experimental Analysis of Double-Wall Impingement-Effusion Cooled Combustor Liners

固定式燃气轮机和航空发动机仍然是未来能源和运输部门的关键技术。特别是在商业航空领域，燃气轮机将是唯一可行的推进方案，即使考虑到半电力推进系统。为了进一步提高热效率，必须提高核心发动机压力比和涡轮入口温度。此外，必须开发新的燃烧概念。燃烧室部件，尤其是内衬，承受着越来越高的热负荷。它们必须使用尽可能少的空气进行冷却，因为空气会直接降低热效率并影响燃烧本身。在这个项目的范围内，创新的冷却概念将进行实验分析。这些新概念基于双壁概念，其中外墙用于在内部产生撞击射流，热壁从背面冷却。最终，空气通过内壁的渗出孔排出，在热侧形成一层保护膜。一个经过验证的测试平台将用于提供新的热学和空气动力学测试数据。热数据将使用红外热像仪获取，空气动力学数据将使用粒子图像测速仪获取。数据将被评估为平稳，并在适用的情况下进行时间分辨。研究结果可为基于双壁冷却的新型燃烧室的设计和评价提供新的模型和关联。

Stationary gas turbines and aero engines continue to be a key technology for the energy and transport sector of the future. Especially in commercial aerospace, gas turbines will be the only feasible solution for propulsion in the feature, even when considering semi-electric propulsion systems. To further increase the thermal efficiency core engine pressure ratios and turbine inlet temperatures have to be increased. Additionally, new combustion concepts have to be developed. Combustor components, especially the liners, are under increasingly high thermal loads. They have to be cooled using the least amount of air possible, since this air directly reduces thermal efficiency and influences the combustion itself. In the scope of this project innovative cooling concepts will be analyzed experimentally. These new concepts are based on a double-wall concept, where the outer wall is used to generate impinging jet on the inner, hot wall cooling it from the back side. Eventually, the air is expelled through effusion holes in the inner wall generating a protective film on the hot side. A validated test rig will be used to provide new thermal and aerodynamic test data. Thermal data will be acquired using infrared thermography, aerodynamic data will be acquired using Particle Image Velocimetry. The data will be evaluated stationary and also time-resolved where applicable. The results can be used to provide new models and correlations for the design and evaluation of new combustors based on double-wall cooling.