Numerical study of heat transfer enhancement by using protrusions in curved pin-fin arrays

Abstract

The trailing edge of a turbine blade constantly faces the harshest conditions, and pin fin is usually equipped for internal cooling channel of trailing edge to augment heat transfer. The present study aims to explore the impact of various protrusion positions on the heat transfer efficiency of a hybrid channel, incorporating protrusions and curved pin fins, under both stationary and rotational conditions. Three protrusion positions (front, middle, and behind) are studied for the range of Ro from 0 to 0.5. The baseline of the curved pin fins channel without protrusions is considered. This study is based on the numerical method of the realizable k-ε turbulence model for calculation. Numerical calculations reveal that arranging protrusions within the curved pin-fin channel can significantly enhance the overall heat transfer performance. Protrusions of front get the best improvement 15.47% in thermal performance factors under stationary condition. Under rotating condition, the arrangement of protrusions also brings improvement of the Nu number on endwalls from 5.32% to 10.74%.