Numerical Simulation of the Water Cooled High Temperature Furnace Flue in the Lignite Fired Boiler

Based on k-¿ two-equation and radiation-convection heat transfer model. The convection heat transfer of the high temperature furnace flue adopting membrane water wall are simulated. The finite difference equations were solved semi-implicitly by a combination of Newton and a secant method. The results of simulation showed that the flue insulating layer in the high temperature furnace is replaced by the membrane water wall. Therefore, the insulation problems of the high temperature flue gas are solved, the heat loss is reduced and the weight of the insulation structure is decreased. Consequently, it can provide powerful theoretical basis for the transformation of the project.