Abstract
The pressurization effect of jet fans in railway tunnels is not only related to the performance of the fans, but also to external factors such as the layout pattern of jet fans. Based on ventilation theory and CFD, the effects of jet fans under various layout combinations on the pressurization efficiency in railway tunnels are studied and analyzed, and the corresponding optimization is carried out regarding the layout patterns. Considering the situation of the Guanjiao tunnel, the expression formula and rational calculation method for the pressurization effect of jet fans are established by means of the theoretical analysis of the jet fans' working principles and air flow status in tunnels. By numerical simulation with a 3D model, various layout patterns of jet fans are studied and the pressurization effect of jet fans is verified. The results show the actual pressurization of jet fans is less than the theoretical calculation. As for the six alternatives, jet fan efficiency is the highest for the one in which four fans would be installed at the middle-lower part of the tunnel. Finally the layout pattern of jet fans for the Guanjiao tunnel during operation period is determined.
Abstract：
The pressurization effect of jet fans in railway tunnels is not only related to the performance of the fans, but also to external factors such as the layout pattern of jet fans. Based on ventilation theory and CFD, the effects of jet fans under various layout combinations on the pressurization efficiency in railway tunnels are studied and analyzed, and the corresponding optimization is carried out regarding the layout patterns. Considering the situation of the Guanjiao tunnel, the expression formula and rational calculation method for the pressurization effect of jet fans are established by means of the theoretical analysis of the jet fans' working principles and air flow status in tunnels. By numerical simulation with a 3D model, various layout patterns of jet fans are studied and the pressurization effect of jet fans is verified. The results show the actual pressurization of jet fans is less than the theoretical calculation. As for the six alternatives, jet fan efficiency is the highest for the one in which four fans would be installed at the middle-lower part of the tunnel. Finally the layout pattern of jet fans for the Guanjiao tunnel during operation period is determined.
2013, Vol. 50 