Research on heat transfer of spraying evaporative cooling technique for large electrical machine

A heat transfer calculation approach of spraying evaporative cooling is presented according to its characters using in large electrical machine. Based on the parameters of coolant, fluid and surface structure the calculation approach is confirmed, and gain the relationship between convective heat transfer coefficient and heat flux. Experiment model of spraying evaporative cooling electrical machine is built, and perform the heating and cooling experiment. The temperature distribution of experiment model is calculated by FEM taking the theoretical result of convective heat transfer coefficient as the boundary. The results of calculation and experiment are consistent, which shows that the boundary of calculation is suitable, and this method can be used in the calculation and design of spraying evaporative cooling electrical machine.