研究堆燃料组件碰撞过程结构响应特性研究

Research on Structural Response Characteristics of Research Reactor Fuel Assembly During Collision

对典型的研究堆燃料组件碰撞过程结构响应特性进行了数值模拟研究,分析了在碰撞过程中燃料组件应力响应特性、燃料元件定位结构的承载特征以及填充缓冲材料对燃料组件碰撞的保护效果。研究发现:在碰撞过程中燃料元件端部附近有明显的应力集中现象,增加燃料元件端部包壳长度可避免应力集中对芯体产生影响;燃料元件端部定位结构承受的载荷显著大于中部,加强端部定位结构的强度可提升燃料组件承载能力;缓冲材料在碰撞过程中对燃料组件具有良好的吸能保护功能,同时能平缓碰撞中的动能变化以及碰撞后的结构振动。

The structural response characteristics of typical research reactor fuel assembly collision process are numerically simulated.The stress response characteristics of the fuel assembly,the bearing characteristics of the positioning structure of the fuel element and the protective effect of the filling cushion material on the collision of the fuel assembly during the collision are analyzed.It is found that there is an obvious stress concentration near the end of the fuel element during the collision,and increasing the cladding length at the end of the fuel element can avoid the effect of stress concentration on the core.The load borne by the end positioning structure of the fuel element is significantly greater than that in the middle,and strengthening the strength of the end positioning structure can improve the bearing capacity of the fuel assembly;the cushion material has a good energy absorption and protection function for the fuel assembly during the collision,and can smooth the change of kinetic energy in the collision and the structural vibration after the collision.