Numerical Simulation And Investigation Of Axial Fan In Subway

The axial flow fan is such important device used in subway ventilation systemsthat people are paying more attention to its performances. It has many characters suchas large flow rate, total head rise and energy consumption. Now the design of the axialflow fan used in subway depends on the test, which needs more manpower andmaterial resources. If CFD technology is applied to simulation of the flow field to aiddesign of the axial fan, the time and cost will be saved for the customers.Fluent6.1 is used to simulate some parameters such as pressure and velocity filedof the axial flow fan, under different rotation speed and stagger angle of fan blades.Fluent6.1 preovides two numerical methods: segregated solver and coupled solver.The former, which employs a discretization process (finite-volume), was used in thismodel. The standard k-εmodel was used to calculate turbulent viscosity and thestandard SIMPLE algorithm was used in pressure-velocity coupling. After thesimulation, the results of total pressure and flow rate were generialized and comparedwith the experimental data. They agreed so well especially in rated flow and pressure.It proved that simulation could provide guidance to design.Through this simulation, I found that it would be difficult to converge if we builtmodel according to the drawing and boundary conditions. Thus it needs to simplifysome conditions and these errors should be checked in tests. In addition,Preprocessing and postprocessing is the key factor in successful simulation, whichneeds rich experiences and more attainment. In this thesis, I summarized someexperiences in building model,generating mesh and setting up boundary conditions. Ihope it can provide help to the next research.