Study On The Heat Transfer In Second Cooling Of Continuous Casting With Asymmetric Spray

With the popularity of the continuous casting process in steel production, we putforward higher requirements to the steel quality while speeding up the production rate ofsteel. In the process of production of the entire cast steel, Continuous casting processplayed an important role in the heat exchanger of the steel. The spray cooling process is thecontrollability highest stage, so we can seek a reasonable cooling method for improving therate of finished steel.In this experiment, we established the model of the two-dimensional inverse heatproblem according welding thermocouple in the steel to calculate the surface heat flux andsurface temperature. At first, we divided the experimental steel at same grid and createddifferential equation for each node. At second, we introduced a functional and usedNewton’s iterative method to optimize the required boundary conditions. The wholeprocess using Matlab programming, then we verify the accuracy of the calculationprocedure, the relative error is10-11.In this paper, we organized and carried out the experiment under Asymmetric spray.We analyzed the cooling process of different location points on the cooling surface; as aresult, we get the change relationship between the surface temperature and heat fluxdensity with time. Thus, there is a more intuitive and rational understanding of the coolingprocess of the continuous casting process, at the same time playing a certain theoreticalsupport.In the process of the vertical injection nozzle cooling, we found the critical heat fluxof jet central location is higher than other points was approximately to2.2×10~6w/m~2.When the plate in the cooling medium, we got that the surface heat flow density decreasedobviously at the jet boundary area, The points outside the jet region processed through anefficient convection after40s and there will be an obvious” film boiling” stage after thecritical heat flux. When we did the asymmetrical cooling experiment, we found the critical surface heatflux of the jet downstream region boundary position higher than the jet central locationapproximately4.3×10~6w/m~2. There had a little rise of the surface heat flow density valueafter60s at the upstream region boundary location. This position which was not sprayed ofupstream was in the air cooling condition in the whole process. The other area which wasnot sprayed at the downstream region underwent an efficient convection after100s and the“film boiling” stage appeared before the critical heat flux. The last point, when the coolingsurface temperature is100-600℃, the heat transfer efficiency of the inclined jet coolingprocess is higher than that of the vertical jet cooling process.