超流氦系统负压低温板翅式换热器新型波纹-锯齿翅片的性能研究

In order to improve the flow and heat transfer performance of the negative pressure low temperature plate-fin heat exchanger in superfluid helium system, a new-type sine-offset fin was proposed by combining traditional offset fin and sine-wavy fin, and the offset density was proposed as a new structural parameter to describe the new sine-offset fin. The physical field of flow and heat transfer in sine-offset fin channel, the comparison of flow and heat transfer performance in three kinds of fin channels, and the influence of fin structural parameters on fin performance were studied and analyzed by numerical simulation. The results show that compared with traditional offset fin and sine-wavy fin, the heat-transfer factor j of the sine-offset fin was increased by 19.97%-38.22% and 25.09%-33.83%, respectively, and the improvement of the comprehensive performance is more obvious at lower Reynolds numbers; the j factor decreases with the increase of wavelength and offset density, and increases with the double waveheight. In addition, the friction factor f decreases with the wavelength and increases with the double waveheight, and increases first and then decreases with the increase of offset density. The new sine-offset fin structure can improve the heat transfer and comprehensive performance of plate-fin heat exchanger. This research may provide a reference for the optimal design of plate-fin heat exchanger.