Evaluation of interfacial heat transfer coefficient based on the experiment and numerical simulation in the air-cooling process

Air-cooling process is a very complex heat transfer involving the heat transfer theory and the fluid dynamics. In the paper, the experiment and numerical simulation methods are used to study the interfacial heat transfer and gas flow in the process of air-cooling, and an axisymmetric model is established to simulate the air-cooling process based on the fluid-thermal-solid coupling method. In the experiment and numerical simulation, the high-speed compressed air is used to impinge and cool the hot metallic surface. The temperatures attained in the experiment and numerical simulation are used to calculate the interfacial heat transfer coefficient (IHTC) by a self-developed inverse heat transfer analysis software. Considering the influence of turbulence model on flow, it found that the SST k - omega turbulence model is more appropriate for the air-cooling process. Based on the SST k - omega model, the effect of sample diameter and jet distance (distance from jet to cooling surface) on the flow pattern and temperature fields is studied, the results show that the temperatures attained in the numerical simulation are in good agreement with those of experiment, and the smaller the jet distance is, the bigger the IHTC is. Finally, the IHTCs under the different jet distance and inlet flow velocity are calculated based on the temperature curves attained in the numerical simulation.