本文研究在环形流道热入口区以及壁面热流沿轴向变化的棒束流道中液金属钠的传热。首先求解在恒定的壁面热流的环形流道中的能量方程。然后把基本解推广到壁面热流沿轴向变化的棒束流道中。理论结果与实验结果吻合良好。研究结果表明,液钠的热入口效应与普通流体很不相同。 This paper studies the heat transfer of liquid metallic sodium in the hot inlet zone of the annular flow passage and in the flow of the rod bundle varying axially along the wall flow. First, solve the energy equation in the annular flow channel with constant wall heat flow. Then, the basic solution is extended to the rod flow path that the wall heat flux changes along the axial direction. The theoretical results agree well with the experimental results. The results show that the thermal inlet effect of liquid sodium is very different from ordinary fluid.