Research Of Strip Temperature Model For Strip Casting-Warm Rolling Process With Direct Flame Impingement

Strip casting-warm rolling process provides a feasible process route for the production of hard-to-working metals,such as 6.5wt%Si steel.The temperature is the most important parameters in this process.In order to ensure rapid response and controlling precision of the temperature regulation in the process,the direct flame impingement technique is used to heat the strip.In this paper,the research status of flame heating and strip temperature model was summarized,and the research work on the temperature model of strip with direct flame impingement is carried out.The main contents of the thesis are as follows:(1)Based on the heat transfer theory and the research of flame heat source,the heat input model of Gaussian distribution was established by analyzing the semi-analytical formulas and empirical formulas of heat source.According to the boundary conditions and environmental parameters,the two-dimensional unsteady equation of heat conduction was established,two-dimensional explicit finite difference equations of inner nodes,boundary nodes and corner nodes are deduced.(2)With Visual Studio 2008 as the development environment,the program design of the temperature calculation of the strip is carried out.The development of each function modules of the temperature calculation program is completed by using the C++programming language.The calculation functions of the heating by fixed single heat source,moving single heat source and moving dual heat source were realized.(3)A self-designed experimental platform was used to carry out experimental research on strip heated with direct flame impingement.The fixed single heat source heating strip was carried out to determine the heat source radius and heat absorption rate in different propane flow and verify the accuracy of the temperature model calculation;the moving single heat source heating strip was carried out to verify the accuracy of the temperature model calculation and predict the high efficiency heat transfer area through comparing measured temperature and calculated temperature.(4)The situation of strip heated with moving dual heat source was simulated.The influences of heat source spacing,thickness of strip,relative moving speed of heat source and propane gas flow on temperature field were studied.Optimized moving dual heat source heating process conditions are obtained with the calculated temperature data,which can provide a reference for the design of the actual direct flame impingement heating device.