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For the outside cabin heat exchanger of wind power generation, the overall numerical simulation plays an important role in its design and optimization. The periodic iterative simulation method proposed in this paper makes up for the deficiency of analogy research using the local model in the previous research of plate-fin heat exchanger so that the research conclusions can be directly applied to practical engineering. The effectiveness of this method is verified by comparing 10 groups of simulation results with experimental results. It is concluded that the maximum relative error of the periodic iterative simulation method is 0.9%, which meets the requirements of engineering calculation. The number of iterations can be reduced to two when only the outlet average temperature is involved, which is more convenient than the dozens of iterations. Furthermore, the effects of altitude, air velocity, air temperature, wave fin structure parameters, and generator power on the performance of heat exchanger are comprehensively analyzed. The results show that larger naturally captured air volume, lower ambient temperature, and lower altitude can effectively reduce the outlet temperature of ethylene glycol solution. When the amplitude and wavelength of the corrugated fin on the airside of the heat exchanger are 0.6 mm and 20 mm respectively, the naturally captured air volume is effectively increased, the overall heat exchange performance of the heat exchanger is further improved. [ABSTRACT FROM AUTHOR]

In this study, influence factors of liquid nitrogen spray cooling, including the parameters of the nozzle, the area of the heat sink, and the flow rate of liquid nitrogen, were investigated experimentally. On the basis of experimental data, experimental dimensionless correlations were obtained. It was shown that the error of correlation with only the Reynolds number (Re) and Prandtl number (Pr) was too low to predict the Nusselt number (Nu). With Re, Pr, the boiling number (Bg), and the Jacob number (Ja), while the error of correlation decreased, the experimental data deviated considerably from the fitting line by the correlation, which was still not suitable for prediction. The reasons for the experimental data's deviation were that the uniformity of the droplet distribution varied with the nozzle aperture, a change in the heat exchange area resulted in the formation of a local gas film, the droplet splash caused by a change in the flow rate influenced the heat exchange. The correlation obtained with Re, Pr, Bg, Ja, and the effective of spray mass flow flux η which was determined as the ratio of the liquid nitrogen mass flow rate involved in heat transfer to the uniform mass flow on the heat surface could be used to accurately predict Nu. [ABSTRACT FROM AUTHOR]