Air Distribution And Thermal Comfort Simulation On Different Ventilation Way In Air-conditioned Train

Thermal environment of air-conditioned train has an important effect on passengers’s comfort and passenger body, physical and mental health, this effect is manifested by air distribution of train compartments, that is, the velocity field and temperature field of train compartment. The regulation of the temperature field and velocity field mainly rely on the car’s air-conditioning system, numerical simulation is an intuitive and effective methods, it is very appropriate to use to study the airflow characteristics of conditioned Train.This paper first introduces the flow field of the status quo at home and abroad of conditioned Train inside, and the theory of numerical simulation and meshing methods; then Airpak software comes with the modeling capabilities and model to establish the train train hard and soft sleepermesh; Airpak software to simulate the air supply parameters for each condition; final calculated results, the analysis of car air-conditioning outlet, supply air temperature, air velocity, temperature field inside as well as the speedthe impact of the field, put forward the optimal conditions, and analyze the pros and cons of various air supply.Based on the numerical calculation of two models, the results of analysis of the temperature field and velocity field distribution characteristics, summed up the formation of the rule and influence factors of the flow field, targeted to improve the working conditions are proposed based on the results of the simulation. Roof grille air supply train hard now widely used, due to the leg of passengers from the outlet to outlet location closer to see the poor comfort, to raise the upper berth passenger leg area temperature bunk passengers airflow will reduce thermal comfort conditions maximum extent alleviate the above problems; instead luggage rack blast, too cold upper berth passenger leg basically solved the problem; two air supply, the airflow velocity inside control below0.35m/s, the vortex characteristics, heat transfer better; berthed passengers and on in the next three thermal comfort are able to meet the requirements, conditions for optimal air supply parameters combination. Soft sleeper cabin air-conditioning system in the grille blast an air supply is also more popular, but the problems they face, such as train hard, as the thermal comfort of the upper berth passengers can not guarantee temperature uniformity, often head hot foot cold "phenomenon, in which the conditions optimal; attached to the air supply in emerging roof, more fully inside the heat exchanger, the temperature uniformity is significantly improved compared to the grille air supply, thermal comfort is also higher, better speed control airflow inside the box, is a worthy air supply conditions of thermal comfort optimal.Through the research on this subject, we find that hard sleeper and soft sleeper beds airflow cause a lot of blast of cold air can not be mixed with air fully with bunk beds just above. Use the numerical simulation method to analyze the airflow research inside organizations. The results of the research provide a valuable reference for the railway passenger car air conditioning designers.