Mathematical Modeling of Cooling High-Temperature Cylindrical Workpieces

摘要

The paper presents the results of modeling the process of cooling a cylindrical metal workpiece made of structural steel by a flowing cooling medium. The authors give a mathematical description of their solution for the problem of convective heat exchange that occurs when a longitudinal water flow is used for cooling. The control volume approach has been used for solving the systems of equations. The parameters of the flow field are calculated by the SIMPLE algorithm. The mathematical model factors in the presence of vapor being generated at the boundary between the high-temperature workpiece and the cooling water flow. It uses the effective vapor volume fraction calculated according to the heat-balance equation. The calculation results obtained by using the proposed model are compared to calculations by a mathematical model that uses criterial equations for determining the boundary conditions on the surface of a high-temperature cylindrical work piece in contact with the water flow. The authors discuss cases of cooling metal workpieces with different initial heating temperatures. The results of the numerical calculations of the heat exchange parameters are analyzed with regard to the time of the cooling process as well as in regard to whether the vapor presence on the cylinder surface is or is not taken into account.