Analysis and calculation of nonlinear flow field and stator temperature field in stator radial ventilating grooves for large hydro-generator in the case of insulation aging

In this paper, the coupling relation between wall temperature, surface coefficient of heat transfer and air speed in a hydrogenerator stator radial ventilating groove is used to set up the 3D stator nonlinear coupled field equations. The 3D isoparametric finite element method and Newton-Raphson method are applied to calculate the coupled nonlinear field. Finally, using a numerical simulation method, the influence of the insulation coefficient of heat conductivity on the stator temperature field is analyzed when the flow field in radial ventilating grooves varies in a nonlinear way.