The high quality steam is important to the safety and economical work of nuclear-powered equipments. Due to the high separating efficiency, Corrugated plate steam-water separator is used to nuclear-powered equipments widely and has been attracting the attention of scientists and engineers as the last stage of the steam separation system. So a detailed numerical simulation is important for further improving the separation efficiency. In this paper, the theoretical researchs on steam-water separating process considering the reentrainment is made. Due to the complexity of reentrainment, the mechanism of Reentrained droplets is analyzied firstly, and critical criterion of film breaking, the sucking ration and the distribution of droplets are acquired. After the mechanism of reentrained droplets in the corrugated plates separator is analyzed, a new spray impingement model was developed which is formulated on the basis of mass, momentum and energy conservation. The physical parameters of reentrained droplets and the critical criterion of splashing can be decided by this new model. Based on the analyses above, the two-phase and three-flow-field numerical model of steam-water separation process in corrugated plates considering to the reentrainment is founded. The idea of wall function was used to simplify the liquid film phase. The CFX software is used to calculate approximatively. Because there is grain transport model but not drop impinging model in the CFX, so a special software to simulate the separating process with reentrainment in the corrugated plates is developed. Single grain dynamics model is adopted to calculate separation efficiency. The effect of inlet velocity, diameter and stage on pressure drop and separation efficiency under the condition of cold state and actual state is obtained.
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