Plate heat exchanger evaporative heat transfer
Evaporative heat transfer of plate heat exchangers includes convective heat transfer and nuclear boiling heat transfer.The evaporative heat transfer process of the plate evaporator is complicated, and the plate heat exchanger has many factors affecting the evaporative heat transfer performance.Plate heat exchangers are rarely used in two-phase evaporative heat transfer, and the existing model applications have great limitations, most of which are heat transfer models for pipe flow or vertical wall flow.
Compared with the single-phase flow, the phase change flow causes the liquid phase to increase due to the gas phase mixing, and the gas phase flow sliding velocity affects the turbulence effect of the liquid film. The frictional resistance of the two-phase flow is made larger than that of the single-phase flow, and the influencing factors are also greatly increased, resulting in a more complicated internal flow state of the two-phase flow.
There are many factors affecting the evaporative heat transfer of the plate heat exchanger, mainly including refrigerant mass flow rate, evaporation temperature, heat flow rate, average dryness of the inlet and outlet, and evaporation pressure. Two-phase heat transfer in plate heat exchangers is difficult to form a more general computational correlation