Numerical Simulation Of Drainage Of Aluminum Foam Under The Constant Uniform Magnetic Field

Aluminum foam is a new type of material made of aluminum alloy and gas.It has both excellent properties of aluminum alloy and gas medium.It has outstanding advantages such as light weight,strong sound absorption performance,low price,and strong thermal insulation,and has become a research focus in recent years.However,during the preparation of foamed aluminum,due to the existence of liquid exudation phenomenon,there will be mutual extrusion and deformation between the bubbles inside the foamed aluminum.Some of the films will become thin and cracked,and the others will become coarse.In the end,the aluminum foam products would have problems such as uneven cell sizes,different wall thicknesses,and accumulation of underlying aluminum alloy materials.In order to reduce the adverse effects caused by phenomena of drainage,and improve the effective preparation efficiency of aluminum foam.It has been proposed to use a constant uniform magnetic field to suppress the leaching process of aluminum foam.Previously,the mathematical models of aluminum foaming liquids mostly used water-based foam mathematical models,without considering the influence of electromagnetic force.This paper focuses on the research of the drainage of aluminum foam under the action of uniform magnetic field,which is mainly divided into three parts.The first part establishes a microscopic model of aluminum foam considering the motion capacity of the gas-liquid interface under the action of a uniform magnetic field.The second part is based on the classical liquid analysis equation,and establishes and solves the aluminum foam analysis solution considering electromagnetic force.The third part simulates the settlement process of particles in the node-Plateau boundary system.The conclusions are as follows,(1)The existence of a uniform magnetic field has a certain inhibitory effect on the flow in the aluminum foam micro fluidic field.This inhibitory effect increases with the increase of the magnetic field strength.Magnetic field suppresses the Plateau boundary more than the node-Plateau boundary system.(2)When the uniform magnetic field is applied at the bottom of the aluminum foam accumulation area,its effect is higher than that at the top and middle.the effect of applying the uniform magnetic field in the early stage of the leaching process is better than the final stage.It is speculated that the uniform magnetic field.The effect of suppressing the drainage of liquid in the blowing foam method is higher than that in the melt foam method.(3)Particles have a certain inhibitory effect on the drainage of aluminum foam.The higher the particle concentration,the stronger the inhibitory effect.When a uniform magnetic field is applied in the fluid domain,the suppression efficiency is improved under the combined action of particles and a constant uniform magnetic field.In addition,different particle concentrations and different magnetic field intensities can achieve the same suppression effect through multiple combinations.Therefore,it is suggested to assist the preparation of aluminum foam by combining magnetic fields with particles in engineering.While reducing the impact of particles on the properties of aluminum foam,maintain and even improve the inhibition efficiency of the leaching process.(4)The introduction of electromagnetic force can slow down the rate of change of liquid content with time and space.And the higher the magnetic field strength,the smoother the curve of the liquid content with space and time.Based on this,the existence of the magnetic field can effectively improve the stability and uniformity of the aluminum foam finished product.(5)As the storage time increases,the stabilization effect of the magnetic field on the overall liquid content gradually increases.At the same time,the relationship between the liquid content of aluminum foam and the connectivity in the existing literature is summarized,so as to predict the connectivity of aluminum foam under the influence of magnetic field.It is thought that the effect of the magnetic field can also reduce the connectivity of foamed aluminum.And the higher the magnetic field strength,the longer it takes for the foamed aluminum liquid film to rupture.This has positive significance for improving the performance of closed-cell foam aluminum products.(6)During the settlement of particles in the node-Plateau boundary system,the flow channel will be blocked.This hinders the flow rate of the internal aluminum liquid.As the number of particles increases,the hindrance gradually increases.