A Numerical Investigation into the Cooling Curves of Stainless Steel Porous Materials for the Quenching Process


Ozsunar A., Peker G.

ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING, cilt.36, sa.2, ss.339-354, 2011 (SCI-Expanded) identifier identifier

Özet

In this study, FLUENT software was used to obtain the cooling curves of porous materials produced by powder metallurgy (P/M). Heat transfer coefficients and the properties of the quenching (water) were changed with the changing temperature. A user defined function (UDF) was written in the C++ language for the varying heat transfer and conduction coefficients, and for the properties of the quenching, after which the UDF was transferred to the FLUENT software. The thermal conductivity of the porous materials was obtained using empirical correlations given in the literature. The natural convection, nucleate boiling, and film boiling processes with and without radiation were considered in the analysis. Various parameters affecting the cooling curves including the porosity, dimensions, initial temperature, and temperature of the bath, were investigated. Cooling curves of the metals were obtained. Results in this work were found to be fairly comparable with those in other numerical studies. The temperature differences on the outer and inner surfaces were significantly high so that cooling curves with different characteristics were obtained due to the low conductivity of the stainless steel. The cooling times and temperature differences increased with the increasing porosity.