Research On The Influence Of Driving Airflow On The Heat Dissipation Performance Of The Locomotive Roof Heat Dissipation Module

With the development of locomotives in the direction of high power,a problem that cannot be ignored has become increasingly prominent,that is,electrical components such as traction motors,main transformers,and main converters will generate a lot of heat during the operation of the locomotive.Therefore,based on the heat dissipation requirements of a freight locomotive model,this paper optimizes the wind side structure of the roof heat dissipation device based on driving airflow heat dissipation through theoretical analysis,numerical simulation and experimental research methods.In addition,the influence of the traveling airflow on the coupling heat dissipation and flow performance of the roof cooling modules with different installation methods and structures is studied.The research work done in this paper is as follows.(1)The structure model of the roof heat dissipation device is established,and the working principle of the structure of the vehicle-mounted heat dissipation module of the driving airflow is introduced;the relationship between the flow performance and heat dissipation performance on the wind side is deduced;the comprehensive performance of the roof heat dissipation device is determined.jf evaluation factor;the governing equations of the simulation are introduced.(2)The simulation model of the heat sink is determined,and tests are designed for the experimental simulation of the structural parameters of the wind side of the heat sink,including the fin spacing,fin spacing,fin height,and radiator thickness.The preliminary results obtained by the factor are further optimized considering the actual locomotive heat dissipation requirements,and cross-experiments are designed for further optimization simulation.The results show that when the fin height is14.3mm,the fin spacing is 3mm,the fin thickness is 0.2mm,the radiator thickness is 200 mm,the jf evaluation factor and the comprehensive heat dissipation performance are the best.Aiming at the optimal structural parameter model designed,change the wind speed and temperature to study the changing law of its flow performance and heat transfer performance.(3)Aiming at the arrangement and installation of the locomotive top of the roof cooling module,the effectiveness of the simulation method of porous media is firstly analyzed,and the parameters of porous media are obtained.Then,by changing different variables(installation method and number of columns),the interaction law of multiple cooling devices of the roof cooling module is studied.The results show that: in terms of heat exchange performance,the cooling power of the three devices mounted on the roof in plum-shaped and diamond-shaped installations increases with the increase of the number of columns;The pressure drops of the three devices on the roof are all different;through the volume power density analysis,the maximum volume power reduction rate is only4.93%,that is,compared with the power that can be improved,the cost increase is very low,so In engineering applications,the maximum power installation method and heat sink width can be selected within the optional range.(4)Combined with the existing experimental conditions,a prototype of the roof cooling device was designed and produced,and an air duct experimental platform was built to conduct experimental research on the pressure drop and heat transfer performance of the roof cooling device prototype.The comparison between the experimental results and the simulation results shows that the maximum error of pressure drop is 18%,and the maximum error of heat dissipation is 4.13%.The simulation results of heat dissipation performance are in good agreement with the experimental results.