Optimization of a staggered dimpled surface in a cooling channel using Kriging model

Abstract

This study presents a numerical procedure to optimize the shape of staggered dimpled surface to enhance turbulent heat transfer in a rectangular channel. Kriging model based optimization technique is used with Reynolds-averaged Navier–Stokes analysis of fluid flow and heat transfer with shear stress transport turbulence model. The dimple depth-to-dimple print diameter ratio, channel height-to-dimple print diameter ratio, and dimple print diameter-to-pitch ratio are chosen as design variables. The objective function is defined as a linear combination of heat transfer and friction loss related terms with a weighting factor. Latin Hypercube Sampling is used to determine the training points as a mean of design of experiment. In the sensitivity analysis, it is found that the objective function is most sensitive to the ratio of dimple depth to dimple print diameter. Optimal values of the design variables have been obtained in a range of the weighting factor.