Study On The Performance Of Double Cycle Cooling System Of Wheel Loader Based On Water-cooled Intercooler

As the main machinery in modern engineering construction projects,loader has the characteristics of harsh construction environment,complex working conditions and long working time,which puts forward strict requirements for the reliability and efficiency of loader cooling system.At the same time,with the rising price of fossil energy and the increasingly serious environmental pollution,the state puts forward new energy-saving and emission reduction standards for off-road vehicles such as loaders.In order to meet the requirements of the new standards,it has important application value and theoretical significance to comprehensively improve the performance of the loader cooling system.At present,the research on the cooling system of major domestic loader manufacturers is still at a certain distance from Europe and the United States and other countries.The stability and energy saving of the products still need to be improved.Based on the topic of "integrated intelligent engineering vehicle equipment research and development for energy saving and safety",this paper conducts the following research on the characteristics of the dual-cycle cooling system of the loader using heat transfer and computational fluid dynamics as the theoretical guidance:(1)Based on the similarity theory,the three-dimensional scale model of the intercooler has been deduced,and the CFD technology is used to simulate the intercooler numerically.According to the simulation results,the internal heat transfer characteristics and resistance characteristics of the air-cooled intercooler and the water-cooled intercooler have been compared.The pressure loss of the charge air in the two types of intercoolers has been analyzed;the effect of the intercooler performance on the working state of the diesel engine is studied by AVL simulation;Comparing the charge air hysteresis of the two cooling methods,the water-cooled intercooler has a lower lag time and a faster response.(2)Latin Hypercubic sampling and CFD simulation are used to design simulation experiments for different corrugated fin structures.The simulation results have been extracted and the optimal corrugated fin structure of the intercooler has been obtained based on neural network algorithm and multi-objective genetic optimization algorithm.According to the field synergy theory,the performance of the optimized corrugated fin is compared and the field synergy angles of the original model and the optimized model have been analyzed.The optimized fin is superior to the original fin in both pressure drop and flow rate.(3)According to the heat generation characteristics of each heat source of the loader,a new dual-cycle cooling system is constructed to realize the "sharing" of heat exchange capacity of the coolant.The difference between the traditional cooling system and the two dual-cycle cooling systems is compared by one-dimensional simulation.On this basis,field tests have been carried out on the V-type working condition and high-speed running condition of the loader,which confirms that the dual-cycle cooling system is effective in terms of power consumption,volume and efficiency.Compared with the traditional cooling system,the pressure loss and other aspects are improved to varying degrees;the energy consumption of the dual-cycle cooling system is significantly higher than that of the traditional cooling system;the performance of the A-type dual-cycle cooling system is better.(4)Based on the double-cycle cooling system of water-cooled intercooler,the characteristics of heat distribution in power cabin of loader are described;the influence of uneven distribution of cooling air on the working performance of radiator is pointed out through simulation of thermal environment in power cabin,which provides theoretical basis for optimization of fan blade structure and arrangement of radiators in power cabin.