Abstract
Microrib is a promising structural optimization method proposed in heat transfer research project of scramjet regenerative cooling channels. In this article, a new type of boot-shaped microribs was designed to enhance the heat transfer performance in mini cooling channels for transcritical n-Decane. Response Surface Methodology (RSM) and Multi-objective Genetic Algorithm (MOGA) were utilized to optimize the regenerative cooling channels with boot-shaped ribs. In order to improve the various design variables on the objective functions, a series of flow and thermal characteristics simulations were conducted. Four geometric parameters (h, w, pi and Re) were adopted as the design variables. The average temperature of the heated wall () and the pressure drop between the inlet and oulet () were selected as the objective functions. The statistical importance of the regression models for and was tested by analysis of variance (ANOVA). Then, the Pareto-optimal fronts were obtained via MOGA. The experimental results indicate that the variables influencing and from highest to lowest impact are as follows: Re, pi, h, w. The optimum designing parameters of the regenerative cooling channels with boot-shaped ribs in transcritical regions are found to be h = 0.18 mm, w = 0.05 mm, p = 3.70 mm, Re = 7449.70 mm, corresponding to the minimum values of =912.439 K and =8485.32 Pa.