FEM simulation and optimization design of flow field in CVI reactor

Chemical vapor infiltration (CVI) is an essential process to manufacture the Continuous Fiber Reinforced Ceramic Matrix Composites. In order to optimize the manufacturing process, a systemic and in-depth study on simulating the flow field of CVI reactor is very important. The flow fields of CVI reactors were simulated by finite element method (FEM) based ANSYS-FLOTRAN of commercial software. For the simple shape component, the flow field is influenced evidently by the lay-mode and arrays of components. The boundary conditions of components are more uniformity and symmetry by parallel arrays of components than that of cross arrays, so the circumfluence in the CVI reactor was decreased. The velocity and pressure difference of the mixed gas were increased with the increase and uniformity of components in parallel arrays. It is key to improve the chemical vapor infiltration quality that reducing the free-space in the CVI reactor. Under the principle of reducing free spacing in CVI reactor, the flow field could be improved by the guide plates in CVI reactor with complex non-conventional shape components, and the circumfluence could be avoided around the components, so the flow fields were optimized.