Study On The Technology Of Waste Heat Utilization Of Mine Vehicle Engine Based On Rankine Cycle

Energy is the essential product of human life.Since the advance of the industrial revolution,the consumption of fossil energy has also witnessed explosive growth in human production and life.In modern industry,the consumption of oil mainly accounts for 35% of the total oil consumption.The vehicle emissions,environmental pollution and energy saving problems have long been the focus of automotive research.The mining industry of the heavy duty truck has larger working load.After exhaust gas turbocharging,exhaust gas still has higher energy.In order to further reduce the carbon emissions of heavy duty mining vehicles,the Rankine cycle technology is adopted to improve the utilization efficiency of the waste gas energy of mining vehicles.The main work of this article is as follows:The theoretical analysis and calculation of the Rankine cycle are carried out,and the related thermal physical parameters,in which affect the thermal efficiency of the Rankine cycle are analyzed,and the methods to improve the waste heat utilization efficiency of the Rankine cycle are obtained.And taking the heavy diesel engine WP12G460E310 as the research object,the heat balance analysis is carried out.The exhaust gas energy of the engine accounts for about 28% ~ 30% of the total fuel energy.At the same time,in terms of the test data parameters of the engine,it is clear that the conversion potential of waste heat can be greater,and the maximum convertible available energy is 31% of the exhaust energy.This paper analyzes the influence of the Rankine cycle working fluid properties on the performance of the cycle,and find out the selection criteria of the Rankine cycle fluid.Research suggests that as the evaporation pressure rises,the Rankine cycle thermal efficiency rises,and as the condensing pressure rises,the Rankine cycle thermal efficiency decreases.Through comprehensive comparative analysis,R123 has been selected as the Rankine cycle,and thus determine the operating parameters of the system.Then,this paper is based on the relevant parameters and combined with the design manual.The four main components of Rankine cycle are designed and calculated,and the thermodynamic analysis and calculation is carried out according to the designed circulation system.By using GT-POWER software cycle simulation model,the accuracy of the model is verified after comparing the simulation value with the experimental data.The final simulation results show that after adding the Rankine cycle system,the total power of the engine can be increased to 6.4%,and the discharge temperature has also decreased significantly.At high speed and high load conditions,the maximum thermal efficiency of the Rankine cycle system can be up to 13%,while at low speed and low load conditions,the efficiency of the waste heat recovery system is low because of the low exhaust energy,and the exhaust temperature is greatly reduced,and the maximum can be reduced by 573 K.The results show that Rankine cycle exhaust gas heat recovery system has great practical value for improving the utilization of exhaust heat of heavy duty vehicle engines.