采用有限容积法对离散热源在水平腔体内引起的自然对流问题进行了数值模拟,通过改变离散热源的间距W和Ra数的大小,分析了不同工况对矩形腔内空气流速、温度分布和热源表面Nu的影响,并对顶部冷却和侧壁冷却两种不同边界条件的计算结果进行了比较.结果表明:W、Ra和边界条件的改变对矩形腔内自然对流换热有显著的影响. The finite volume method was used to simulate the natural convection problems caused by discrete heat sources in the horizontal cavity. By changing the W and Ra numbers of the discrete heat sources, the influence of different working conditions on the air velocity, temperature distribution and heat source Surface Nu and the results of two different boundary conditions of top cooling and side wall cooling are compared.The results show that the changes of W, Ra and boundary conditions have a significant effect on the natural convection heat transfer in rectangular cavity.