Analysis And Simulation Of A New Method For Flow Passage Margin Elimination Of Axial Flow Fans

Fans have a wide range of important applications in power plants, but the large number of the applications also makes fans consume large amounts of power plant electricity. Statistics show that 30% of electricity consumption of power plant are caused by the fans. Therefore, a thorough study of the performance characteristics of the fans, a comprehensive understanding of the problems in fans’operation, and the transformation for operation optimization of fans, and improving operational efficiency of the fans are critical for the energy-saving of the whole power plant.After the fully understanding of the operation conditions of the two-stage variable pitch axial flow induced draft fan in a 600MW power generation unit, and the problem of the situation that the whole pressure margin and margin of the gas flow volume are too large, from the perspective of energy saving, This paper puts forward A new method for flow passage margin elimination of axial flow fans---the elimination of the number of the rear rotor blades.After carrying out a detailed mapping and data collecting of every part of the whole induced draft fan, this paper built up a three-dimensional prototype model of the fan and made the transformation of the flow passage accordingly. Then the GAMBIT was used to divide the grids for all the models. After the mesh files are imported to the Fluent and the determination of the boundary conditions and computing areas, the Fluent was used to carry on the calculation of the numerical simulation. The operating performance of the prototype model as well as the model after transformation was thusly possessed. After setting different inlet conditions for several simulations, the operating performance of the models after the transformation of the flow passages was obtained. And by comparing the operating performance of the prototype model and the transformed ones, it is possible to verify the feasibility of this transformation plan for the elimination margin of the fan as well as energy-saving. This paper will provide empirical support for the theory for the future transformation of the fan.