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Show Application of a mathematical modeling to the development of a muffle type continuous heat treating furnace Masaru TAKEI *, Takehito IMANARL Tsuneaki NAKAMURA Energy Technology Research Institute, Tokyo Gas Co., Ltd. 1-16-25, Shibaura, Minato-ku, Tokyo 105 Satoni YASUOKA, Ichiro NAKAMACHI Industrial Gas Sales Department, Tokyo Gas Co., Ltd. 3-13-1, Minami-senju, Arakawa-ku, Tokyo 116 Abstract This paper describes practical and engineering application of a C F D numerical method to the development of a muffle type continuous heat treating furnace equipped with the FDI (Fuel Direct Injection) regenerative burner system. The furnace is cylindrical and consists of combustion and reducing zones, which are divided by a muffle to bright-anneal a steel strip in the reducing zone. The muffle should be heated uniformly to avoid serious thermal damage and to maintain high quality of the products. The FDI regenerative burner system, which is proven to create uniform heat transfer profile in steel reheating furnaces, has been applied to the muffle type furnace. When designing furnaces with the FDI regenerative burner system, a number of design parameters specific to the system should be considered to optimize the furnace configuration and operating condition. To facilitate the design, a 3-dimensional detailed numerical analysis is conducted and the performance of the furnace is predicted. Flow, combustion, thermal conduction, and convective and radiative heat transfer are taken into account in the combustion zone, while thermal conduction and radiative heat transfer are calculated in the reducing zone. The muffle was treated as a conducting solid. The heating curve of the steel strip is successfully predicted by modeling its movement in the reducing zone. The furnace configuration regarding the location of the regenerative burners is optimized by the state-of-the- art numerical technique. The paper also introduces an intelligent program named 'if-Diss' (Industrial Furnace Design Intelligent Support System). It allows interactive preprocessing for the numerical simulation with powerful database of various analytical models and useful grid generator. If- Diss has modeled more than 70 furnaces. Coded with J A V A language, if-Diss will be used by an internet browser via the internet or intranet. 1 |