Optimal Design Of The Smoke Collection Device Of Range Hoods And Numerial Simulation Of Flow Field In The Multi-blade Fan Of Range Hoods

Range hood,as the main "electrical facilities" of kitchen equipment,becomes more and more necessity and favorite in life.In this paper the fume collection device and the multi-blade centrifugal fan,the core parts of the Range hood,are numerically simulated by CFD.Based on the rules of maximum flowrate,minimum pressure loss and the best appearance,optimal design result of the fume collection device is achieved by changing the variable structure parameters,meanwhile,calculating the mass flow and pressure loss,analysing the internal flow of fume collection device.Two models of multi-blade centrifugal fan are numerically simulated,nine running cases are selected for each model.In the numerical simulation of three-dimensional internal flow,the three-dimensional time averaged N-S equation and the two different turbulent model(standard k-εand RNG k-ε)are used,Finite Volume Method,non-uniform tetrahedral meshes and the SIMPLE algorithm are selected.The standard wall function is adopted near the flow near wall,the rotating coordinate system are used to calculate the flow of impeller.The results of simulation are compared with experiment data,the difference between them is annalized.The results show the many important phenomena of the internal flow in the multi-blade centrifugal fan,such as the vortices in the blade channels,the flow separation at the suction side of the impeller,the second flow in the volute and the development tendency.The results of simuliaton with turbulent model(Standard k-εturbulent model and RNG k-εturbulent model)are compare to those of the experiments,It is shown that the RNG k-εturbulent model is more suitale to simulate the internal flow of multi-blade centrifugal fan.