对单晶硅化学气相沉积（ＣＶＤ）反应器在沉积过程中的流场进行了初步分析．通过数值求解三维层流 Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程，研究了反应器内浮力效应所引起的流场对称性破坏．结果表明，由于存在浮力效应，轴对称 几何体中也会发生非轴对称流场分布，从而影响单晶硅的均匀生长． The flow field during the deposition of single crystal CVD reactor was preliminarily analyzed. By solving the three-dimensional laminar flow Navier-Stokes equations numerically, the symmetry failure of flow field caused by the buoyancy effect in the reactor was studied. The results show that due to the buoyancy effect, non-axisymmetric flow field distribution will also occur in the axisymmetric geometry, which will affect the uniform growth of monocrystalline silicon.