The Development And Study Of New Stirrer Impeller Used In Automotive Paint Stirring

In the 21st century,China has become the rapid growing country in the automobile industry,whose automobile production and sales among the world forefront.Painting occupies an important position in the automobile industry,and paint stirring is an important part which cannot be ignored in the painting process.Automobile paint stirrer is used to complete automobile paint stirring operation to prevent solute precipitation,so that achieve the goal of stir well.In this background,this paper is committed to developing a new type stirrer impeller which is suitable for automobile paint stirring,and then carries on the relevant study.First of all,the physical properties of the paint are analyzed and its mathematical model is established.The physical properties of paint are mainly density,viscosity,heat capacity and so on.The paint is a kind of incompressible fluid whose density can be used to deal with constant.Temperature change of the material is not within the range of the flow field analysis,so the temperature dependent physical properties are not considered in this paper.Automobile paint is a kind of non-Newtonian fluid whose viscosity changes with the change of velocity gradient in the process of paint flow,so it needs to curve fit its viscosity to establish the appropriate mathematical model.Secondly,the structure of stirrer impeller is designed,and the numerical simulation is carried out with the finite element model established.The geometric model of fluid domain in stirred tank is established with the software of SolidWorks,after the structure of stirrer impeller was designed.Fluid domain is divided into grids by the ANSYS ICEM tool,and the grid is imported into the CFX-Pre tool to establish the finite element model.The standard k-? model and the multiple frames of reference method are used to calculate the gas-liquid two phase flow.Numerical simulation is done in the CFX-Solver tool.Furthermore,the law of the flow field in stirred tank is studied,and stirring performance is analyzed.Stirring performance analysis is a direct means to study the stirring effect.The performance and regularity of the flow field are explored,including the free surface,the stirrer power,the power number,the shear rate field,the turbulent kinetic energy and the velocity field.The effect of stirrer impeller structure design on the stirring is discussed.The results show that this new type stirrer impeller has better stirring performance.In addition,the fixed height of stirrer impeller from tank bottom is optimized.The relative position of impeller in the flow field is an important factor affecting the stirring performance,in the case of determinative impeller and tank.The effect of fixed height change on the stirring performance is analyzed.It is expected that shear action and overall convective circulation ability as high as possible with energy consumption as low as possible,with three stirring performances including energy consumption of impeller,shear action and overall convective circulation ability in flow field taken as evaluation indexes of this optimization problem.The optimal solution of the fixed height of stirrer impeller from tank bottom is obtained.Finally,the static structural analysis of the impeller is carried out through the method of fluid-structure interaction.The solid structure field of this stirrer impeller under the loading condition is solved within Workbench platform by using the method of partitioned solution and one-way coupling.The results show that the stiffness and strength properties of this stirrer impeller are good.At the same time,the stirrer shaft is also designed.