PWR蒸気発生器の二次系圧力損失の簡易的な予測手法に関する研究（U字管部の評価モデル構築検討）

抄録

Improvement of Pressurized Water Reactor (PWR) thermal efficiency has strong effects on the plant economy and uranium resource economy. PWR has two main systems, the primary system including reactor and the secondary system including turbine for generating electricity. Steam Generator (SG) exchanges the heat from the primary system to secondary system. For improving the thermal efficiency, the prediction of heat and mass flux in PWR SG is important. In this study, the simplified prediction method of SG with economizer considering the effects of U-Tubes area has been developed to predict the pressure drop of the secondary system. The developed evaluation model was verified by comparing with the measured value of KWU type SG of Grafenrheinfeld PWR plant in East Germany. In the developed model, SG was divided into nodes along the secondary coolant flow. The total pressure drop of SG was obtained by the sum of static head loss, friction loss, acceleration loss and local loss. The following conclusions were obtained from this study. (1) The simplified prediction method of the pressure drop has been developed. (2) The prediction accuracy with Drift flux model is better than that with homogeneous model. The prediction accuracy for this method with Drift flux model is about 10%. (3) The static head loss is larger than the other pressure drop factors. The prediction accuracy of the void fraction and the heat transfer in SG is needed to be better for evaluating static head loss and total pressure drop more correctly.