【摘要】 本文针对环形空间内自然对流的研究现状，采用扩大计算区域办法确定边界条件，对一端开口的环形空间进行了将导热、对流、辐射耦合在一起的数值模拟，并加入了氩气的物性，使得计算结果与快中子增殖反应堆的实际情况相一致。计算结果显示，流动呈现两细胞的半循环流动，该结论与前人的研究结果一致。此外，由于采用计算区域整体模拟的办法，同时得出了固体内的温度场。更多还原

【Abstract】 In the pool design of fast reactor, the roof structure is penetrated by a number of pumps and heat exchanger units that are cylindrical and differ in size. Between the sodium pool surface and the roof is a layer of hot argon gas that can flow into the small annular gaps between the components and the roof containment as a thermosyphon. It is important to predict the temperature of the argon and the temperature inside the components and roof containment. For numerical research it is difficult to determine the boundary condition on the open end. Usual method of treatment on the boundary condition is to use data from experiments or to make some assumptions. A new consideration of the boundary conditions is introduced for taking account of the flow at the open end. The computational domain is extended into the big space attached to the open end of the annulus. This paper conjugates all the conduction, convection and radiation together and solves the problem successfully by using PHOENICS as the CFD code.更多还原