Numerical Simulation Of Airflow Within The Subway Cars And Thermal Comfort

Vehicles of Shenyang Metro Line 2 is taken as study object in this article.The related information of the subway air-conditioning, experimental methods and laboratory instruments have been introduced in detail. At the same time,corresponding numerical simulation is established with Realizableκ-εturbulence model by using Fluent software. The error of the results is below 10%, which shows that the feasibility of the numerical model has been proven to be ture. In this model, a numerical simulation with variety of air flow condition is made and the relationship between various factors is probed out.The humanbody heat diffusion is usually estimated and flow field influence on it is neglected.The first and second boundary condition have been usually used in the simulation for human body heat diffusion, while the use of such boundary conditions have been proven unable to overcome the many fundamental flaws. The problem of coupling heat diffusion between the people and the environment is dealed with the method of the third boundary condition.Crowded passengers for subway air-conditioning is an unavoidable problem. Old methods of solving heat source is not adopted in this article. But a model of subway car with 85 passengers is established, using the calculation program on human and environmental coupling heat diffusion which has been proven, to simulate the vehicle's cooling steady state of the airflow inside subway car. At the same time, temperature, humidity, velocity, air age are analyzed by using the EDT, PMV-PPD and other indicators to make a thermal comfort evaluation with the passengers and the vehicle airflow and thermal comfort in terms of strengths and weaknesses, meanwhile the reasons is given out. Based on the discovery of the problems, eventually a set of optimized programs on the air conditioning has been offered for the optimization.