Numerical Study on Flow and Heat Transfer Characteristics of Swirl Cooling on Leading Edge Model of Gas Turbine Blade

Abstract

In this paper a numerical simulation is performed to predict the swirl cooling on internal leading edge cooling passage model. The relative performances of four kinds of turbulence models including the standard κ-ε model, the RNG κ-ε model, the standard κ-ω model and the SST κ-ω model in the simulation of the swirl flow by tangential inlet jets in a circular pipe are compared with available experimental data. The results show that SST κ-ω model is the best one based on simulation accuracy. Then the SST κ-ω model is adopted for the present simulation. A circular pipe with a single rectangular tangential inlet jet or with two rectangular tangential inlet jets is adopted to investigate the swirl cooling and its effectiveness. The influence of the Reynolds number and the inlet to wall temperature ratio are investigated. The results indicate that the heat transfer coefficient on the swirl chamber increases with the increase of Reynolds number, and increases with the decrease of the inlet to wall temperature ratio. The swirl pipe with two tangential inlets could get a heat transfer enhancement of about three times to that of the nonswirling pipe, while swirl pipe with one tangential inlet could get a heat transfer coefficient 38% higher than that of the nonswirling pipe.