Cooling of spherical products: Part II—heat transfer parameters

Abstract

This paper presents a study on the determination of the heat transfer parameters, namely surface heat transfer coefficients, thermal conductivities, thermal diffusivities, specific heats and Biot numbers, for the individual product being cooled with water and with air. An analytical model was developed to determine the surface heat transfer coefficients of the products depending on the thermal properties and cooling process parameters. The results of the present study indicate that surface heat transfer coefficients decrease with increasing batch weight in water cooling and increase with increasing air flow velocity in air cooling. The proposed model can be used to determine easily and accurately surface heat transfer coefficients of different spherically shaped objects subjected to cooling.