Cooling Research And Structure Optimization Of Ventilated Brake Disk Based On CFD

With the rapid development of automobile industry and the increasing automobile speed,people pay more and more attention to the safety performance of vehicles,the problem of heat dissipation of the brake disc is one of the important factors that affect brake efficiency constant,therefore research on brake disc thermal performance has important significance.This paper aims at the problem of heat dissipation of brake discs with different ventilation structures.Based on the related literature in China and abroad(the first and second chapters),the following researches are carried out:First,a numerical simulation method based on ANSYS platform was designed,and SolidWorks was selected for 3D modeling of the brake disc with given structural parameters;The ICEM CFD was used to set up the static and rotating domains of the computational model,and the grid partition was combined with the structured grid and unstructured grid;The initialization settings of material properties and boundary conditions were set up in FLUENT,and the test results of air mass flow and convection heat transfer coefficient of brake disc were calculated.Compared with bench test,it was found that the error of simulation results was small,which proved that the numerical simulation method was accurate(Chapter 3).Secondly,based on the original brake disc ZB model,a cylinder radial straight line cooling rib brake disc ZP was designed,and referring to the ideas of designing impeller fan,there two other brake discs QB and QP were obtained by controlling the entry angle and outlet angle of the curve.The results of air mass flow rate and convective heat transfer coefficient of the 4 kinds of brake discs were calculated by FLUENT,and the distribution of the convective heat transfer coefficient in the axial and radial distribution of the brake disc,the velocity distribution and the static pressure distribution in the inner flow field of the brake disc were analyzed as well.Then a comprehensive analysis and evaluation of the heat dissipation performance of the 4 brake discs was carried out.It was found that the cylindrical radial distributed heat dissipation brake discs(ZP and QP)have obvious advantages in uniform heat dissipation(Chapter 4).Finally,taking air mass flow rate and heat dissipation power as indexes,a 4 factor(cylindrical radius,exit angle,entrance angle and radiating rib number)and 5 level orthogonal test was designed for the cylinder radial curve distributed heat dissipation brake discs,and 25 sets of test results were calculated;The effect of 4 structural parameters on the air mass flow and the heat dissipation power was obtained by the extreme difference analysis;The single factor influence fitting curve of the index was obtained by MATLAB,and the influence of the structure parameters on the single factor of the two indexes of the brake disc was analyzed;The dual objective optimization method was used to translated the two objective problem into a single objective problem,and the optimal parameters scheme of the brake disk was determined.(Chapter 5).