Steady State Thermo-property Analysis On Gear-box Of ZL80 Wheel Loader

The large-scale wheel loader is one of local recipe construction machinery,which is fetched into the market and developing in our nation in recently years.In company with the promotion of loader function,the gear box drive system ran from traditional mechanical drive to combine transmission,which collect engine electricity liquor on one-piece. The drive system's thermal value large amounts rose relative to gear power-driven transmission,but gear-box powerhouse dome useful space can't increase relevantly,so the systemic heat dissipation conditions went into more and more execrable and gear-box's work reliability reduce. So this paper use project analysis software—ANSYS analyze the wheel loader power gearshift gear-box steady-state temperature field distribution.The paper adopts ANSYS THERMAL ANAIYSIS Model,analyze the wheel loader power gearshift gear-box thermal field distribution along with heat condition in unit time,find out the primary effect factor in gear box thermal field distributive. The analyses can provide valuable reference for power gearshift gear-box thermal behavior of the wheel loader.Creating gear-box grid model and count boundary condition is quite importance and difficult,when using ANSYS analyses the power gearshift gear-box thermal field distribution .The paper compromise CAD and ANSYS software geometry modeling character create power gearshift gear-box finite element model. First of all, use CAD software drawn power gearshift gear-box sectional view and serve as DXF figure style,apply special interface software DXFTOANSYS produce command stream file that ANSYS can discriminate. And then,lead the command stream to ANSYS born the plan that composed by dot and dash,create power gearshift gear-box geometrical model by Boolean operation in preprocessor. In the end,use mesh divide instrument (Mesh Tool) divide geometry dummy free net,net density control adopt brainpower unit size control,mode size distinction set as two level. Pass by mesh divide receive power gearshift gear-box finite element grid model apply constraint and load,in the end derivation.This paper chooses the surface coefficient of heat transfer h between object and around fluid and around fluid temperature as boundary condition. When calculate surface coefficient of heat transfer between object and around fluid, use heat transfer about fluid flows slab heat convection theory and fluid current circular pipe heat convection theory,figure out differ work environment case body inside and outside wall coefficient of convective heat transfer along with each transmission shaft coefficient of convective heat transfer. When calculate around fluid temperature,use power gearshift gear-box fever and radiate theory receive power gearshift gear-box thermal balance thermal design formula, at MATLAB software iterative computation out equilibrium temperature (dubbing internal lubrication temperature).This paper use aforesaid means,first of all,simulate power gearshift gear-box different step transition different transfer route each frictional contact surface unit time temperature rise bring about temperature field distribution. Analytic result proclaim:frictional contact surface maximal temperature rise numerical value is about 5~10℃in unit time ; in consideration of thermal build up factor,power gearshift gear-box heat production becomes more severity. At this foundation this paper simulate analyses the power gearshift gear-box steady-state temperature field distribution. According to analytic result,gear-box reach balanced state case body inner drive assembly have the same equilibrium temperature lubricating oil equilibrium temperature;gear-box case body presence by high to low temperature gradient distribution,this because heat convection and conductive synthetic action consequence;same work environment gear-box reach balanced state steady-state temperature field distribution approximation homology; gear-box each wall heat interchanging area large enough thus coefficient of convective heat transfer value entirety thermal balance impact indefiniteness ; gear-box work on same environment although vary shift work step but experience long enough time can reach the same temperature field distribution,this distribution decision balanced state temperature field distributive major factor is ambient temperature (that is external flow aerial temperature ).