Research Of CFD Simulation On Indoor Air Distribution In The Valve Hall Of The Converter Station

In the projects of HVDC transmission, the valve hall of converter station which is a special type of large space building has unique characteristics, there are many complicated equipments in the valve hall which usually have large scales and own huge heat dissipating capacity. And the valve hall has a strict requirement for electromagnetic shielding. There is nothing more for the good operation of the air-conditioning system in the valve hall. So the research of air distribution and effect of air-conditioning system is meaningful to make the operating of converter station goes well and is helpful to the economics of the air-conditioning system.This research is on the basis of the project of Gezhouba-Shanghai±500 kV HVDC transmission which is the first HVDC project in China. The research object is the air-conditioning system of the valve hall which lies in the converter station of Shanghai. The traditional top supply air-conditioning scheme was designed in this research and was analysed by the software of Airpak. At last the valve hall's temperature field, relative humidity field, velocity vector and the isoline of the mean age of the air were forecasted by CFD simulation.Through the analysis of the results of CFD simulation, some problems were found in the air distribution of the top supply air-conditioning system. The bottom supply air-conditioning scheme was brought forward as the improved scheme. Then the impact to the air distribution of the bottom air-conditioning scheme which are caused by three critical factors was analysed. The three critical factors are temperature difference, the scale of the opening and the height of the air-inlet. Furthermore, the three factors' comprehensive effect to the air distribution and the economics of the air-conditioning system was analysed by the way of orthogonal experimental design. Finally, the best combination of the three factors was determined.By comparison to the top supply air-conditioning scheme and the bottom supply air-conditioning system from the result of CFD simulation, in the premise of the same air-conditioning plant it was found that if the valve hall use the bottom supply air-conditioning scheme the average of indoor temperature can reduce by 3.29℃, the energy using coefficient can increase by 40.51%, and the uneven temperature coefficient can reduce by 31.26%, additionally the average temperature of the valve surface can reduce by 2.96℃, and the area of the valve surface where used to having a hot temperature can reduce a lot.