Resfriamento de placas por fluidos através de canais internos: análise da configuração e design construtal

Abstract

Vascularized plaque technology is one of the most promising in the field of thermal sciences and has been gaining notoriety for its performance in cooling and refrigeration applications. The use of tree-shaped inner tubes, parallel tubes and coils are examples of approaches found using this method of cooling solids. The objective of this work was the development of a high-performance inner tube configuration, based on the principles of Construtal Theory, with a square shape with a central reentry, which reached both the ends and the center of the plate. The solid's material is inspired by a gap-filling substrate used in the electronics industry and the cooling fluid is water. The physical system was computationally modeled as a threedimensional domain, where the equations of mass balance, momentum and energy are valid for a Newtonian fluid in permanent laminar regime. The Construtal Design Method was used to define the system, degrees of freedom, constraints, as well as the evaluation method of the system, as its configuration is modified to achieve the best thermal performance. For the analysis of the effects of the degrees of freedom and the search for the best configurations, the response surface method was used. With a variation of three degrees of freedom, systems subject to two flow rates were evaluated, featuring Reynolds numbers of 100 and 1000. The proposed configurations were numerically solved by computational fluid dynamics. It was observed that the parameter that has the greatest interference in the performance of the system is the length of the pipe in the longitudinal direction, responsible for giving shapes from flattened, with the pipe centered at the center of the solid, to quadratic shapes, where the pipe extends to the ends of the warm body. The results obtained allowed the determination of geometries with performance gains of up to 44% among the simulated cases for Reynolds equal to 1000 and 7% for Reynolds equal to 100, following the trends projected by the temperature contour maps obtained from the method of adopted response surface.