基于自然对流的控制棒驱动机构温场研究

在新一代反应堆控制棒驱动机构耐温等级提升后，为分析取消控制棒驱动机构强制通风系统是否可行，建立了基于单台控制棒驱动机构流场的计算模型，合理确定了求解方法和边界条件，并通过与试验结果进行拟合，进行了控制棒驱动机构群全尺寸模型的温场和速度场计算，得到基于自然对流的控制棒驱动机构温场效应。研究结果表明，通过自然对流可以将控制棒驱动机构运行产生的热量完全带出堆坑，不存在堆坑窝热情况，并且随着控制棒驱动机构群总输出功率的增加，堆顶区域的自然循环强度也增加，可以达到冷却控制棒驱动机构的效果。因此，耐温等级提升后的控制棒驱动机构可以取消强制通风。 

Study on Temperature Field of Control Rod Drive Mechanism Based on Natural Convection

After the improvement of the temperature resistance level of the control rod drive mechanism(CRDM) of the reactor, in order to analyze whether it is feasible to eliminate the forced ventilation system of CRDM, a calculation model of the airflow field intended for single CRDM is established to determine the calculation method and boundary condition, which is conducted by fitting with the experiment results. The temperature field and the airflow field of the full-scale CRDM clusters are calculated, and the temperature field effect of the full-scale CRDM clusters is obtained based on the natural flow field. The research results reveal that the natural convection could take the heat generated by the CRDM clusters out of the reactor pit without pit fever effect. Moreover, as the CRDM clusters output power increases, the natural circulation intensity increases as well. The natural convection could cool down the CRDM coils. Thus, the forced ventilation system could be eliminated with the improvement of the CRDM temperature resistance level.