Thermal-mechanical Coupling Analysis On Drum Brake Of Medium-duty Truck

Drum brake is common brake for vehicle and widely used by current commercialvehicles because of its great braking power and costlessness,However,in practicalusing,many ineffective problems should be faced.its main phenomenons are frictionineffectiveness,heat fade and cracking.These problems will seriously affect the safty andreliability performances of vehicle ,so it is significant in practice to study on the drumbraking equipment.The working process of drum brake is a complex thermal-mechnical couplingcourse,in this course both heat and force together lead to braking ineffectiveness and drumcracking problems.To solve these problems,by means of direct thermal-mechanicalcoupling theory, the Abaqus software is applied to simulate the working course of thebrake equiped on the rear axle of the truck load capacity 6 tons.It contains twoconditions:emergency braking and braking along long-distance downhill,Each conditioninclude three kinds of working enviorment:no tempreature filed,air-cooling,water-cooling.In emergency braking condition,the brake working status in the situation of deceleration4.5m/s2is analyzed primacily and 6m/s2simply.In long-distance downhill brakingcondition, the working status of continue braking distance 1000 meters along thedownhill grade 10% is emulated.Analysising the coupling results,The distribution of temprature filed and stressfield,deformation amount,the brake shoe to drum contact situation are principlly conceredto research on the fields variation pattern and the temprature and cooling conditioninfluence to the brake drum.The result indicts that in emergency braking condition whataffects the stress field is the expansion force of brake shoe,While the long-distancedownhill braking is a dangerous condition and the main influence factor is the tempraturefield.