Heat transfer analysis of a liquid cooling device using thermoelectric elements

This article deals with the CFD simulation of heat transfer inside a heat exchanger of a unique liquid cooling device which innovatively combines a two-circuit liquid cooling system with an accumulator and a new cooling core consisting of Peltier modules. Peltier modules have been used as power elements to cool the medium, which allows heat to be transferred from one side of the cell to the other without moving or noisy elements, thus achieving quiet cooling without vibrations, which can be very beneficial for specific purposes. The used custom-made heat exchanger is specific for its open primary circuit, which also serves as a heat accumulator. In order to obtain data that serve as input conditions for CFD simulation and for subsequent comparison and evaluation, experimental measurements were performed on a physical device. The aim of the simulation is to predict the total time required to cool the medium under given conditions, model the flow of media inside this type of exchanger, and determine the efficiency of the whole device in cooling a specific amount of media using a set of Peltier modules and exchanger, which can be useful in situations where it is undesirable for the refrigerated medium to come into contact with the cooling elements, either due to a hazardous environment or in order to maintain cleanliness standards. This device was able to cool down 2 L of secondary circuit media in slightly over 40 min while showing overall efficiency 14.376 %. The efficiency of the exchanger during the experiment was 94.1 %. This points to the fact that the Peltier modules are responsible for the significant decrease in efficiency, and the use of this cooling configuration is appropriate in situations where efficiency is not a major requirement.