Calculation of Ventilation Cooling, Three-Dimensional Electromagnetic Fields, and Temperature Fields of the End Region in a Large Water–Hydrogen–Hydrogen-Cooled Turbogenerator

According to the complex structure characteristics of a 330-MW water-hydrogen-hydrogen-cooled turbogenerator, the flow network within a half-axial segment of the generator was established. The total flow rate, pressure, flow rates of various ventilation ducts, and the chambers in the generator were obtained after solving the equations of the flow network. The 3-D transient electromagnetic field in the generator end was calculated, and the eddy-current losses of the end parts were gained. Using the finite volume method, the fluid and thermal mathematic and physical models for the whole end region were given. The flow velocity and the pressure values from the flow-network calculations were applied to the end region as boundary conditions, and the losses measured from electromagnetic field calculations were applied to the end parts as heat sources in the temperature field. Thus, both the distribution of the temperature of the end parts and the distribution of the fluid flow in the whole end region were obtained under rated operating conditions. Comparing the calculated temperature results with the test values, the errors meet the engineering requirement. All of the aforementioned data will provide an effective basis for accurately calculating the temperature of the end parts in a large turbogenerator.