Abstract The modified one-dimensional thermal hydraulic program RELAP5/MOD3.3 was developed to simulate the natural circulation characteristics of an integrated reactor. The ocean motions were realized by adding additional acceleration in the source term of momentum equation. The pressure drop and heat transfer correlations of helically coiled tubes were adopted. The effect of natural circulation characteristics on integrated reactor was studied under rolling, heaving and inclined motions. Simulation results show that the core inlet temperature has no significant change under those three ocean conditions. The average fluctuation value of core mass flow rate is less than the steady-state value and decreases with the increasing rolling angle under the rolling motion. Besides, critical period was observed. In the heaving motion, the average fluctuation value of core mass flow rate is equal to the steady-state value which is different from the rolling motion. The steam equilibrium quality changes slightly in different heaving acceleration. In the inclined condition, the core mass flow rate is decreased with the increasing inclined angle and excessive inclined angle will cause the steam unsuperheated and this may affect the performance of the turbine.

中文翻译：

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海洋运动作用下自然循环运行的集成堆热工水力特性研究

摘要 开发了改进的一维热工水力程序RELAP5/MOD3.3，用于模拟集成反应器的自然循环特性。海洋运动是通过在动量方程的源项中添加额外的加速度来实现的。采用螺旋盘管的压降和传热关系式。研究了在滚动、垂荡和倾斜运动下自然循环特性对集成反应器的影响。模拟结果表明，在这三种海洋条件下，核心入口温度没有显着变化。岩心质量流量的平均波动值小于稳态值，并且在滚动运动下随着滚动角的增加而减小。此外，观察到了关键时期。在起伏运动中，岩心质量流量的平均波动值等于不同于滚动运动的稳态值。蒸汽平衡质量在不同的升沉加速度下略有变化。在倾斜工况下，堆芯质量流量随着倾斜角的增大而减小，倾斜角过大会导致蒸汽不过热，从而影响汽轮机的性能。