LES Simulations Predicting Heat Transfer and Wall Temperatures on Turbine Inlet Guide Vanes at High Fuel-Air Ratios

摘要

Cooling flow reacting with pockets of fuel-rich mixtures from high fuel-air ratio combustors can cause undesired heat release near inlet guide vane walls, increasing the heat flux and wall temperature of the vane. Analytical capabilities are needed to accurately model this phenomenon and thus aid in the design process. Large Eddy Simulation (LES) has the potential to provide the necessary analytical capabilities. To demonstrate this, simulations were performed using both Reynolds Averaged Navier Stokes (RANS) and LES on a turbulent channel flow and a laboratory inlet guide vane geometry. The boundary layers were resolved in all cases to eliminate errors associated with wall functions. Results show that both RANS and LES capture the temperature distribution well for cases without near-wall chemical reactions. However, LES (because it captures the turbulent fluctuations in the flow) provides the means of predicting near-wall temperature gradients when pockets of fuel-rich gases interact with the vane cooling flow. Results demonstrate that LES can be an effective tool in the analysis of turbine inlet guide vane cooling schemes with high fuel-air ratio combustors.