Combustor-turbine aerothermal interaction
Multi-stage turbines have losses due to various sources of interference. Reducing these losses, which are due to the geometry of the turbine vane, but additionally affected by the complex aerothermal flow at the combustor outlet, is imperative in optimizing turbine efficiency. In order to simulate the flow and temperature field in the downstream of the combustor, we built a customized 3-stream wind tunnel and combustor simulator with a turbine nozzle linear cascade (Figures 1 and 2). Total pressure measurements will be obtained before and after the nozzles, which will provide information on aerodynamic losses, such as that shown in Figure 3. The temperature will also be measured, to examine the effects of radial profile factor, and hot streak propagation downstream. By comparing the lab measurements with CFD, we hope to provide physical insight into these loss mechanisms, and thus enable loss reduction and improvement of aerothermal performance.
Figure 1. Custom 3-stream wind tunnel.
|Figure 2. Combustor simulator (left), and turbine nozzle linear cascade (right).
Figure 3. Swirler flow field and nozzle guide vane losses .