Numerical And Experimental Study Of A Compact Water-cooled Radiator

Inspired by the widely-used stirred tanks in the chemical discipline, a compact water-cooled radiator possesses a turbine was presented. It is different with the traditional water-cooled radiators, there are no micropump and connected channel in the present radiator, instead, there is a sealed chamber with a turbine inside. When the heat is conducted into the sealed chamber from the bottom of radiator, the motor-driven turbine stirrers the water, then thermal convection occurred between the wall of chamber and flow field.In order to study the flow field distribution in the sealed chamber and the temperature distribution of the water-cooled radiator, the commercial software FLUENT was used to simulate the working condition. The simulation results could reveal some phenomena which were difficult to observe directly in the experiments, and provide directions of further optimization. By the means of simulation, it was confirmed that different flow fields caused by different turbines would affect the convection heat transfer. The suitable turbine is advantageous to the formation of flow field, thus the turbine selection is an important method of optimization. The cooling capacity of a ? 50 mm turbine with 4 blades was slightly superior to an impeller had the same structure.Based on the simulation results, a water-cooled radiator with the same structure of simulated model was made, and a set of experiments were conducted to test its cooling capacity when the ambient temperature was 30?. The deviation was less than 6.3% between simulation and experiment and the corresponding reasons were briefly analyzed, in terms of experimental design, operation method, simulation model's simplification, etc. To validate the performance of the water-cooled radiator, a solid aluminum heat sink of the same size with the radiator was also tested as comparison. In these tests, the data recorded were the temperature of heat source cooled by radiator or heat sink with different power inputs. The results showed that at the value of 85.2W, the temperature of heat source cooled by the present radiator was lower than the one cooled by heat sink by 7.5?, and the advantage of radiator was demonstrated. At last, it was efficient to increase the rotation speed of the turbine to strengthen heat transfer, but the stability of the system would be reduced when the rotation speed reached 400 rpm in the experiments.