Flow and Heat Transfer Characteristics of the Two- phase Cooling Fluid inside the Hollow Conductors of Evaporative Cooling Turbo-generator

In the inner evaporative cooling system of turbo-generator stator, the forced circulation mode is utilized and the pump was chosen as the driving force, for the biggish flow resistance of cooling fluid inside the hollow conductors of horizontal arrangement. In this cooling system, the flow and heat transfer characteristics of the two-phase cooling fluid inside the hollow conductors play an important role to the operation and cooling effects of system. In this paper, the flow resistance of cooling fluid and the temperature distribution of hollow conductor were analyzed deeply through the simulation and experiment. The simulation results of wall temperature of hollow conductors were compared with the experimental results and it was shown that the prediction accuracy of simulating is satisfying. The influences of the lengths of saturated and subcooled boiling on the heat transfer performance of system were discussed.