| As a typical heavy-polluting enterprise,coking enterprises have become increasingly stringent in environmental protection policies in recent years,and their economic benefits and viability have also declined year by year.However,traditional coke ovens are mature and difficult to achieve major breakthroughs in both the structure of the furnace body and the design concept.Therefore,companies are gradually turning their attention to heat recovery coke ovens with better environmental benefits.In the early days,people’s design of heat recovery coke ovens was mainly based on two methods: experiment and experience,but these two methods would cause greater economic and time loss.With the rapid development of computational combustion and computer simulation technology in recent years,computational fluid dynamics(CFD)simulation technology has been applied to the research of coke oven thermal characteristics due to its flexibility,convenience,low cost,and easy operation.This paper takes a new type of heat recovery coke oven operating in a factory as the research object,and first establishes a suitable mathematical model for the entire furnace model.The coke bed is simplified into a porous media model,and the volatile matter precipitation law is coupled to the coke bed porous media model in the form of a mass source term using a user-defined function UDF to simulate the diffusion characteristics of volatile gases inside the furnace.The temperature field,flow field,and component concentration field inside the furnace are calculated by CFD simulation software and compared with the actual operating data.It is found that the error is small.It can be seen that the simulation geometric model is simplified and the mathematical model established in this paper is more reasonable.In this paper,a decoupling algorithm is proposed for the problem that the direct coupling quadruple arch combustor-carbonization chamber is computationally expensive and difficult to converge.The whole furnace model is decoupled into the steady-state non-premixed combustion process in the four-arch combustor and the nonpremixed combustion process in the carbonization chamber.First,the heat balance of the combustion chamber is calculated to obtain the average heat flow value through the two-chamber partition wall,which is used as a boundary condition of the singlechamber simulation of the carbonization chamber.This processing method has a good optimization effect on the simplification of the geometric model of the coke oven,the control of the number of meshes,and the overall calculation amount.In addition,this article aims at the problem of large temperature fluctuations in the carbonization chamber of the new heat recovery coke oven,and simulates calculations by changing the deflection angle of the primary air inlet and the flow ratio of different inlets.It is concluded that when the deflection angle of the primary air inlet is 15° on the y-axis,it has a better improvement effect on this problem;in addition,four sets of working conditions with different flow ratios are compared,and the results show that the 2:1:2working condition.In addition,it can effectively reduce the unevenness of the temperature distribution inside the furnace and has a better heating effect on the coal cake. |
