内容提要: |
Multi-blades centrifugal fan (MCF) is widely used, especially in the field of range hood, for its excellent exhaust airflow rate compared to axial fan. However, some MCFs are inadequate to cater for the required enhanced performance as a result of increased system resistance. Therefore, structure parameters optimization of MCF to improve aerodynamic performance has become a focus of research. This report focus on the effect of inner guide vanes on the aerodynamic performance of multi-blade centrifugal fan (MCF) used to range hood. The Reynolds-averaged Navier-Stokes equations with the RNG k-ε turbulence model are discretized and solved by Fluent. A detailed comparison of dimensionless characteristic coefficients of flow, pressure and power, between the origin MCF and the MCF with inner guide vanes is conducted for a full exhaust condition. The results suggest that the MCF with inner guide vanes perform better in terms of both flow and pressure coefficient. The exhaust airflow rate increases by 6.4% at working condition of No. 6, and there is a best efficiency point for the MCF with inner guide vanes at flow and pressure coefficient of 0.25 and 1.05, respectively. By comparing the flow field between the origin MCF and the MCF with inner guide vanes, it is found that the inner guide vanes effectively reduce flow loss near volute tongue areas. |