The Hxd <sub> 1 </ Sub>-type Electric Locomotive Thermal Environment Numerical Simulation, And

With the great development of locomotive technology, the harmony series high-power AC electric locomotives represented by HXD1 electric locomotive are produced and put into use. They improve the transportation capacity of China's railway and promote the modernization of technologies in railway equipments. The cab air-conditioning system is the main component of electric locomotive cab. The ventilation system of mechanical room is critical to guarantee the running of electric locomotive. The electric cubicle cooling system can guarantee the low-voltage electrical equipment under reliable operation. Therefore, The study on HXD1 electric locomotive's indoor thermal environment is very meaningful.The paper mainly studied on HXD1 electric locomotive with the computational fluid dynamics (CFD) software to simulate locomotive cab, mechanical room and electric cubicle.First, the evaluation of the thermal comfort and the economical efficiency was made in cab cooling conditions. It validated that the air conditioning in the most unfavorable external conditions, could satisfy the requirements of wind speed and temperature, could give the driver a more comfortable driving environment. Then comparison of the running effect in two heating conditions showed that the mode running by air conditioning and the back wall heater was better to control indoor temperature. From the simulation for different wind-back modes, the mode with slotted outlet was better, in which the driver felt comfortable and the homogeneous degree of flow field was improved.Ventilation and cooling systems of mechanical room were simulated. The results showed that the wind speed and temperature distribution were within a standard requirement in both cases which the compressor's fan was on and off. The research on the effect of system air volume and ways of exhausting on flow field found that the overall room temperature could be controlled by ventilation volume, but the temperature in the high-temperature region would not be significantly decreased as the air flow increased, while the reasonable position of the outlet can be targeted to reduce the indoor maximum temperature.Finally, it has established three dimensional numerical model of electric cubicle cooling system and has done numerical simulation, getting velocity field and temperature field of its cooling system through calculation. The comparison with experimental results has proved the rationality of its design, and it compared heat dissipation performance of the system under the condition of different fans and different heat source positions, working out that collocation of fans is decisive in forced air cooling flow field,and the rise of the speed of fans can improve heat dissipating efficiency, which will go down with the increase of power, and reasonable heat source positions can optimize flow field and improve heat dissipation performance. Higher heat components were better to place in the main flow channel, while the air flow and the thermal buoyancy near the devices had the same direction.This research proves that it is feasible to analyze and optimize the electric locomotive air conditioning and ventilation cooling system with the numerical analysis method. The reasonable suggestions on air flow organization could be valuable references to design and optimize the electric locomotive air conditioning and ventilation system.