Development Research On Eelectric Air-condition System Of 165 Bulldozer

Air conditioning system has now become the standard configuration of engineering vehicles,but the current all use the belt-driven air-conditioning system.The compressor of this air-conditioning system is directly connected with the engine through a belt,and the engine of the engineering vehicle is generally arranged under the cab,so that the position of the air conditioning system is restricted.Maintenance the corresponding parts and refrigerant lines will have a difficult,and the compressor through a belt connected with engine directly,which makes the compressor speed affected by rotational speed of the engine,poor working stability,Air-conditioning can not be used in parking.With the promotion of electric vehicles,electric air-conditioning system gradually becomes popular.Due to use the electric drive,the compressor can adopt fully-enclosed structure,which can reduce the leakage of the refrigerant.Based on the air-conditioning system for electric vehicles,used the structural basis of 165 bulldozer to development the available electric air conditioning system for engineering vehicles.In order to reduce the trouble in the maintenance,and make the air-conditioning system can be used when the vehicle has stopped.First,the geometry model of 165 bulldozer was built through CATIA software,and the cooling load of the cabin has calculated through the relevant formula,and the relevant parts of the electric air conditioning system was calculated by the relative properties of R134 a refrigerant.The fixed bracket of the electric air conditioning system was built by CATIA software.In order to verify whether the strength and vibration of the fixed bracket of the electric air condition is up to the standard,the relative strength analysis and modal analysis are carried out by HyperMesh software.Results showed the support of themaximum stress was 17 MPa,the minimum displacement was 0.176 mm,less than the standard value of the material;The 6 order modal analysis of vibration frequency in the fixed bracket minimum was 43.5Hz,far more than the normal working frequency of bulldozer cab.Secondly,the electric compressor performance test system and vibration test of electric air-condition system had verified the hardware performance of the electric air-conditioning system.The results met the user requirement;then temperature test of the cab had carried out,measuring point selection conformity with the provisions of GB,the test conditions for 290 K air temperature,air velocity for the 5m/s,but we found that measuring points temperature of the single air-supply have big difference,which provides a reference for the optimization of the follow-up study.The cab hybrid grid was built by Gambit software,and the flow field of driving room under two air supply modes simulated by the FLUENT software.The authenticity of the simulation verified through the comparison between simulation value and test data under5m/s in one air supply.Then simulated the flow field of single and double inlet under air velocity 4~6m/s;The air distribution and thermal comfort ADPI index were use to evaluate the two kinds of air supply,the double feed air form was better for the flow field;The economic of the electric air-conditioning system was calculates by three point interpolation method;The electric air conditioning system could save fuel costs 4770 yuan per year.In this paper,through development the electric air conditioning system of the 165 type of bulldozer.The proposed research methods and research results have a certain guiding role for the design of the electric air conditioning system of the engineering vehicle.