蒸汽发生器出口管参数对核泵入口流场的影响

Influence of steam generator outlet pipe parameters on inlet flow field of nuclear reactor coolant pump

为研究蒸汽发生器出口管参数对核主泵入口流场的影响,将蒸汽发生器下封头与核主泵统一建模,采用CFD方法对其耦合模型进行全三维流场仿真计算.结果表明:蒸汽发生器出口管长对核主泵入口流场有较大的影响,且该影响在入口管较短时尤为明显,随着蒸汽发生器管长的增加,这种影响逐渐减小,核主泵入口流场趋于稳定;蒸汽发生器出口管的位置对核主泵入口流场紊乱度的影响相对较小,且不同位置管内流场发展趋势相近,但是会对流场的高速区以及低速区产生的位置造成影响;蒸汽发生器出口管中的流场极为紊乱,并在开始部分存在较大的回流区;随着流场的发展,在离蒸汽发生器出口350 mm附近回流区消失,之后流场逐渐趋于稳定,但是流场的偏心现象不会消失.

According to the scale model experiment,it is found that the outlet pipe of the steam gene-rator(SG)has an obvious non-uniform inflow.In order to study the influence of the SG outlet pipe parameters on the inlet flow field of nuclear reactor coolant pump(RCP),a unified model of the SG lo-wer head and the RCP was established,and the three-dimensional flow field was simulated by CFD method.The results show that the outlet pipe length of the SG has a great influence on the inlet flow field of the RCP,and the influence is particularly obvious when the inlet pipe is shorter.With the increase of the pipe length of the SG,the influence gradually decreases,and the inlet flow field of the RCP tends to be stable.The location of the outlet pipe of the SG has little influence on the turbulence flow field of the RCP inlet,and the development trend of the flow field in the different positions of the tube is similar,but it has a great impact on the position of the high-speed and the low-speed regions of the flow field.The flow field in the outlet pipe of the SG is extremely disordered,and there is a large recirculation zone at the beginning.With the development of the flow field,the reflux phenomenon di-sappears around 350 mm from the SG outlet,and then the flow field gradually becomes stable,but the eccentricity of the flow field does not disappear.