Influence Of Key Structure Parameters On The Descaling Nozzle Performance

Under the condition of high temperature,the surface of the billet will form a layer of oxide-scale as the oxidation reaction.Before the slab rolling,it is necessary to remove the oxide-scale on the surface of the billet,otherwise the oxide scale will pressed into the steel billet,which will serious influence the surface quality of steel.Using the mechanical impact of the high pressure water to remove the oxide scale(High pressure water for removing phosphorus)is currently the most common and effective method.Descaling nozzle is the key component of high pressure water for removing phosphorus.As the jet flow formed by the nozzle jet is convergent,jet angle can change in large scope,force uniform,so the descaling nozzle is widely used in the descaling process.The change of the nozzle structure parameters can influence the nozzle jet performance.In the study of the descaling nozzle jet flow field,the content of the research includes the following several aspects.(1)In the case of other parameters constant,using CFD software to study the change of different V-shape groove form the Angle of export expansionθ,the depth of inner cone hole h,the inlet contract angle of the internal surface α.Numerical simulation with the three key structure parameters of the model.Research the effect of these single factor variable to jet angle,jet volume,jet impact force.(2)Using the method of orthogonal experiment gives the structural parameters of the combination of discrete sites.Using the extremum difference analysis and variance analysis method to analysis the interaction of major and minor relationship,determine factors of the test for the jet performance of nozzle design parameter.Find out the rule of index changing with factors and trends,provide the direction for further test.(3)Using the MATLAB software to build the BP neural network to forecast the descaling nozzle performance.Build the BP neural network training database,through orthogonal experiment table and numerical simulation.Using the database to train the BP Neural Network,and fitting of the mapping from nozzle design parameter to nozzle jetperformance.Then test its predictive effect.(4)Building descaling nozzle test experiment platform.Using the experizental methods to analysis the jet performance of different structure parameters.Investigating the characteristics of flow-versus-pressure,the spray angle-versus-pressure,the jet impact force-versus-pressure,the force distribution-versus-pressure.Compared the prediction of the performance of the nozzle using the method of numerical simulation with the experimental results.As a result,using the numerical simulation method can predict and analysis the influence of key structure parameters on the descaling nozzle performance.