Numerical Investigation on Influence of Fan Speed and Swirling Gas Injection on Thermal-Flow Characteristics in Nitrocarburizing Furnace

Abstract

This study was carried out to analyze the ow and heat transfer characteristics in a furnace, and to evaluate the in uence of the two major design factors for improving the ow mixing and heat transfer. The grid system was constructed using ANSYS ICEM (V.17.0), and numerical simulations were conducted using the commercial CFD code (ANSYS Fluent V.17.0). The fan plays an important role in ow mixing and convective heat transfer in the furnace. Accordingly, temperature uniformity was improved with an increase in the fan speed owing to an enhancement of the convective heat transfer. Moreover, when swirl ow was applied to the inlet gas, temperature uniformity was improved in the lower section of the furnace. This is because the swirl ow of the inlet gas improved the ow mixing in the vicinity of the gas inlet where it is not affected by the rotational force of the fan. Controlling the swirl intensity of the inlet gas with lower fan speeds is more energy ef cient because ow mixing and temperature uniformity could be improved suf ciently.

Numerical Simulation of the Flow and Heat Transfer in an Electric Steel Tempering Furnace

“…MRF is an acceptable modeling approach that has been used successfully in axial [19], centrifugal [20], and other kinds of fans [21]. Additionally, a previous study using a nitrocarburation furnace with a fan [22] was modeled using the MRF method.…”