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Show Tokyo Gas has developed a CFD numerical method to predict the performance of various industrial furnaces. The numerical method is capable of predicting complex interactive phenomena generated by fluid flow, combustion and convective and radiative heat transfer to encourage intelligent design of innovative high perfonnance furnaces. The numerical method substantially facilitates the design and optimization of innovative industrial furnaces such as the one equipped with the FDI regenerative burners. This paper describes the results of numerical investigation to optimize the design parameters of furnaces equipped with the FDI regenerative burner system. The paper also introduces an overview of a newly developed CFD tool called if-Diss (industrial furnace design intelligent support system). This CFD package features a state-of-the-art numerical method with a userfriendly CAD-like front end processor to allow furnace engineers an easy, interactive execution of numerical modeling. Application of Numeri~~l modeling to a reheating furnace and a forge furnace This chapter describes the application of the "if-Diss" CFD numerical method to the development of two high temperature furnaces equipped with the FDI regenerative burner system. Figs. 2 and 3 show schematics of a reheating furnace and a forge furnace respectively. The reheating furnace is box -shaped and reheats steel slabs prior to the hot rolling process. The furnace has a door at its ceiling, through which steel slabs are charged and discharged by a crane. The furnace has in total 4 burners, two of which are installed at one of the two side walls and the other two at the opposite side wall. The forge furnace heats steel billets up to 1200 - 1300 C prior to the forging process. The furnace has a front door at one of the furnace side walls, through which steel billets are charged. The furnace has 10 burners, each five of which are installed along one of the opposite side walls of the furnace. Both the furnaces need to create unifonn heat flux profile to the steel materials to maintain high quality of the products. High NOx emission as well as high running costs need to be reduced. Application of the FDI-regenerative burner system has been considered to improve the performance of the furnaces. In the regenerative burner system, all the burners are equipped with regenerators and a set of two burners operate together. One burner is in frring mode while the other behaves as a flue with a regenerator storing the heat of flue gas. After a certain period of time, the firing mode switches and the combustion air is preheated by the regenerator. This switching-over procedure promises a high waste heat recovery of the system. Since the regenerative burner system creates somewhat unique heat transfer characteristics compared to 3 |