螺距对星形螺旋燃料棒束通道内流动与传热特性的影响

Influence of Pitch of Flow and Heat Transfer Characteristics in Helical Cruciform Fuel Bundles

采用SST k-ω湍流模型对不同螺距的星形螺旋燃料棒束通道内流动换热特性进行数值模拟研究。分析了燃料棒螺距对棒束通道内冷却剂的速度、压力、温度分布、搅混特性及换热特性的影响。结果表明,冷却剂在星形螺旋结构的诱导下产生横向流动,增强了搅浑作用。随着螺距的减小,冷却剂横向流动速度增大,压力降增大,流体换热Nu数增大,流体换热性能提高。

The flow and heat transfer characteristics of the helical cruciform fuel bundle with different pitchs were numerically simulated by using the SST k-ω turbulence model. The effects of the pitch on the velocity, pressure drop, temperature distribution, mixing characteristics and heat transfer characteristics of the coolant in the bundle were analyzed. Results show that the lateral velocity of the coolant is mainly caused by the helical cruciform structure. The lateral flow velocity, the pressure drop and Nu number increase with the decreasing of the fuel rod pitch.