Flow and Heat Transfer in Rotating Cavities with Radial Throughflow

Abstract

In modern gas turbines, turbine section operates under severe thermal conditions. Effective cooling of the turbine section is required to keep their safe working. This study deals with flow and heat transfer in the low-pressure turbine section which has cavities formed by an assembly of turbine disks. This paper focuses on the heat transfer characteristics of the most upstream disk surface, and the effects of the forced convection with radial throughflow and the natural convection in a centrifugal acceleration field were investigated through flow visualization and heat transfer experiments. This study employs three dimensionless parameters which govern flow and heat transfer in rotating cavities. These are throughflow Reynolds number, rotational Reynolds number, and Rayleigh number. The results showed that, for the effect of the forced convection, meat Nusselt number did not increase monotonically with increasing throughflow Reynolds number at a constant rotational Reynolds number, and for the effect of bouyancy force Nusselt number decreased with increasing Rayleigh number.