Experimental And Computational Study Of The Rotating Turbine Disk Cavity Internal Flow Field Distribution

In modern industrial gas turbines and aero-engines, a small percentage of the compressed air is bled off for cooling and sealing purposes. Some of the air is used for cooling the turbine blades and nozzle guide vanes, and part of it is employed to cool and seal the turbine discs. It is crucial for cooling high temperature parts in aero-engines to master the rule of the flow field in turbine discs air cooling system.Taking the rotating cavity with micro-turbine as research object, the numerical and experimental researche both have been applied to study the flow characteristics inside the rotating cavity. The five-hole probe system was used to measure the velocity of the flow. Two-dimensional axisymmetric solver, incorporating the K- ε two equations turbulence model, was used to compute the flow. The influence of rotational speed, inlet mass flow rate and axial location was summarized.The results reveal that the ratio between inflow inertia force and rotating effect is the main factor that influences the flow. It also indicates that the flow is mainly controlled by the inflow inertia force at lower rotating speed, and by rotating effect at higher speed, by both factors at transition speed. The results show that the flow structure is also controlled by the de-swirl nozzles inlet angle. Then, the distribution of tangential, radial and axial component of velocity is given in the paper.The experiment data is reasonable good and agrees closely with that of the computation.