Experimental and numerical analysis of a novel constructal design for canopy-to-canopy liquid cooling systems

Abstract

The cooling capacity of canopy-to-canopy flat plates with the coolant inlet and outlet on the same side of the plate was analyzed in detail, both experimentally and numerically. A novel constructal design was proposed to derive the diameter of each branch of canopy-to-canopy configurations. Thanks to the predicted diameter ratios, the new design results in a reduction of the coolant pumping power of 60 % to achieve the same maximum temperature as a traditional configuration with equal diameters in all branches. Four canopy-to-canopy configurations with a number of branches ranging from 2 to 5 were designed based on this innovative constructal approach to optimize the cooling capacity of flat plate systems, keeping the same fluid volume for all of them. The resulting designs were tested experimentally and modelled for steady state and transient cooling operations. A higher number of branches improved the steady state cooling performance under continuous heating, as the 5-branches configuration yielded the lowest maximum and mean temperatures while maintaining similar temperature homogeneity in both experimental measurements and numerical simulations. The maximum deviation between experimental and numerical results was 1.4 °C for both maximum and average temperatures, allowing the validation of the numerical models. For the transient cooling process, the flat plates experienced a progressively faster temperature reduction over time as the number of branches in the design increases, accelerating the cooling process by 14.7 % when increasing the number of branches from 2 to 5. The results show that the 5-branches canopy-to-canopy configuration has an excellent cooling capacity with a limited pressure drop to circulate the coolant.