Investigation Of Turbine Cascade Flow With Leading Edge Film Cooling

Increasing the turbine inlet temperature is one of the most important ways to improve the engine efficiency. The turbine inlet temperature can reach 2000 K nowadays which is much higher than the melting point of turbine material. Therefore, it is necessary to protect the turbine. Film cooling technique is a most common technique using in turbine blades. However,cooling gas could affect greatly the flow of turbine cascade.This paper based on computation flow dynamic focus on the turbine cascade flow affected by leading edge film cooling technique. This paper tries to find conclusion about turbine cascade flow in different situations, that is, with and without leading edge film cooling,with different flow quantities of cooling gas and with different incident angles of cooling gas.The results indicate that the leading edge film cooling can affect greatly the turbine cascade flow, especially the leading edge of turbine where the flow is very complicated. This paper also indicates that the higher the flow quantity of cooling gas is, the more the film cooling can affect, and the wilder the film created is. But as the air flow changes, the total pressure recovery coefficient does not change much. With the increasing of incident angle at a small range, the flow has a bigger distance with the surface of the blade, with the decreasing of incident angle, the flow is closer to the surface. But generally speaking, the influence caused by the angle is less obvious than that by the air flow factor with the same changing.With the help of simulation and figures of cascade flow got in this paper, it can get theoretic result about the flow with leading edge film cooling. This can also provide basic help to do research about film cooling in other parts of turbine in the future.