核电机组低压安注试验限流孔板调整计算

Adjustment Calculation of the Limit Orifice Plate for Low Pressure Safety Injection Test of Nuclear Power Plant

当反应堆发生事故时需要安全注入系统向反应堆注入冷却水以减轻或控制事故发展。核电站日常运维中需要执行低压安注试验以验证不同工况下安全注入系统向反应堆注入冷却水的流量是否满足设计要求。当试验结果不满足设计要求时需要对低压安注系统相应管路上的限流孔板孔径进行调整。通过对限流孔板计算分析和复杂管路的管路特性的分析结合伯努利方程给出了低压安注试验中涉及的限流孔板孔径调整计算方案。通过某核电站4号机孔板调整实例验证,理论计算的孔板孔径与实际偏差不足1%。实践表明,提出的限流孔板孔径调整计算方案能够满足工程需求。

When an accident happened at the reactor,the safety injection system should inject cooling water into the reactor to reduce or control the development of the accident.In the daily operation and maintenance of nuclear power plant, low pressure safety injection test needs to be performed in order to verify whether the flow rate of the cooling water meets the design requirement at different conditions.In case the design requirement is not met,adjustment should be made to the aperture of the orifice plate on the corresponding pipeline of the low pressure safety injection system.Through the analysis of the limiting orifice plate and pipeline characteristics of the complex pipeline,the calculation method of the adjustment of the aperture of the limiting orifice associated with the low pressure safety injection test.Through the example of a nuclear power plant orifice plate adjustment verification, the actual deviation of the theoretical calculation of the orifice plate aperture and the actual one is less than l%.Practice shows that the calculation method of the orifice diameter adjustment of the current limiting orifice can meet the engineering requirements.