Simplified Mechanism Model And Numerical Of Tubular Reheating Furnace

As a main heating equipment in petrochemical process,furnace is one of the most energy-consuming equipment.The optimization and simulation of its production process has become a key topic in recent years.Because of the complex chemical and physical reaction process and the complexity of the coupling in internal heat transfer processes,it is more difficult to directly optimize parameters and simulation.The object of reaseach in this paper is an atmospheric furnace of 6.0 million tons/year.With the simplified simulation modeling and numerical simulation to study the tubular furnace.The following is the main work:(1)A simplified mechanism model of a new tubular heating furnace has proposed,which used to simulate fuel burning,radiation and convection heat transfer in a tubular heating furnace.The model numerically simulate the relationship between gas temperature and fuel air in the furnace and the numerical connection between the gas and the heated fluid.Compared the simulation results with the comparison of the field data show that the developed model offers significant potential for usein real-time optimization and control,which provides a basis for the research of the tubular heater.(2)Using CFD commercial fluid simulation software FLUENT to simulate the tubular heating furnace.According to the actual size of the tubular reheating furnace,a three-dimensional geometric model is established.The temperature field,flow field and concentration field in the furnace are simulated by FLUENT6.3.The whole process of turbulence,combustion and heat transfer is obtained.In the process of simulation,three-dimensional geometric modeling and meshing of furnace,burner and tube are carried out by Gambit software.The k-? equation model model is used to describe the turbulence.Different combustion models are compared with radiation models.(3)The results show that using PDF non-premixed combustion model,discrete coordinate radiation model(DO model)are in good agreement with the industrial operation data.The results show that there is a large reflux zone near the bottom burner of the furnace,which plays an important role in the combustion and temperature distribution in the furnace.At the same time,there exists uneven temperature and heat flow on the surface of the furnace tube to the fire side and the back fire side,which will seriously affect the service life of the furnace tube.The simulation results provide theoretical guidance for optimum design of large reheating furnace.