Research on a new equivalent diameter for predicting pressure drop in hollow conductor in evaporative cooling generator

In evaporative inner cooling generator, the total pressure drop in hollow conductor is composed of liquid phase and two-phase flow pressure drops. In recent researches, the two-phase flow pressure drop in hollow conductor was researched deeply and detailedly, but the liquid phase flow pressure drop was seldom researched. In fact, the liquid phase flow pressure drop is an important component of total pressure drop and the basis for computing two-phase flow pressure drop. In this paper, an experiment table used for researching flow characteristic in hollow conductor was established, on the basis of work condition in 300MW turbo-generator stator. Through analyzing the shape feature of cross section of hollow conductor, a new equivalent diameter was proposed. The comparison results between the simulation results and experiment data, show that the prediction accuracy of total pressure drop in hollow conductor can be raised by using the new equivalent diameter.