Research Of Numerical Simulation On The Superheater Deposition Of A 75t/h Straw Boiler

With economic development, oil, coal and natural gas resources are increasingly strained. "Greenhouse effect" and other environmental issues attract more and more attention. Second only to oil, coal and natural gas, biomass is considered as the fourth largest energy, which becomes the focus of research and attention, especially in the boiler of straw. The straw boiler superheater generally exists with the problem of deposition severely. This thesis uses fluent software to processed numerical simulation for the superheater of 75t/h straw boiler in some plants.Based on the high temperature superheater model simplified appropriately, the physical model of high-temperature superheater is created. The split, partial encryption technology is adopted to mesh the superheater and a high quality mesh is obtained. The flow of superheater area is gas-solid flow. With numerical simulation for gas, we use the standard k-εmodel and SIMPLE calculation. Through the boundary conditions set, the velocity field is obtained. Through the analysis of the velocity field, parts of superheater tube foul are gained. For the numerical simulation of the solid phase, the particle trajectory model is used. The trajectory of the particle simulation is based on the gas phase. In this thesis, the same size particle trajectory with different wind speeds and the different size particle trajectory with same wind speeds are studied. The conclusion that the small size particles are easily to foul on the first part of the superheater and the right part of the superheater are easily wear by the big size particles is gained. Based on the numerical simulation results, the soot blower is transformed and good results are obtained. So the correctness of the numerical simulation is verified.