In a certain nuclear reactor, the coolant channel is a cross-type channel. There is little research about bubble rising behavior in this kind of channel, but the neutron detection would be affected by the bubbles. Through comparing with previous experiment, proper numerical model has been determined, and the cross-type channel under different helium flow rates is studied with CFD software Fluent. Research shows that the bubble distribution exhibits some similarities under different helium flow rates, and the bubbles tend to rise near the tube wall; In the axial direction of the flow channel, the bubble coalescence can be observed, which leads the void fraction in the axial direction to increase first and then to be stable; The void fraction increases with increasing helium flow rates.

在某个核反应堆中，冷却剂通道是十字型通道。关于这种通道中气泡上升行为的研究很少，但是中子检测会受到气泡的影响。通过与先前的实验比较，确定了合适的数值模型，并使用CFD软件Fluent研究了不同氦流量下的交叉通道。研究表明，在不同的氦气流量下，气泡的分布表现出一些相似性，并且气泡倾向于在管壁附近上升。在流动通道的轴向上可以观察到气泡的聚结，这导致轴向上的空隙率先增加然后稳定。空隙率随着氦流量的增加而增加。