TY - JOUR
T1 - A validated numerical investigation of the effects of high blockage ratio and train and tunnel length upon underground railway aerodynamics
AU - Cross, Daniel
AU - Hughes, Ben
AU - Ingham, Derek
AU - Ma, Lin
PY - 2015/11/1
Y1 - 2015/11/1
N2 - In order to ensure the safety and comfort of passengers and staff, an underground railway requires an extensive ventilation and cooling system. One mechanism for underground railway ventilation is the movement of air induced by trains, termed the 'piston effect'. This study investigated the effect of altering the blockage ratio of an underground train upon the ventilating air flows driven by a train. First a computational model was developed and validated with experimental data from literature. This model was scaled to represent an operational underground railway with high blockage ratio and the blockage ratio varied to evaluate the effects upon ventilation. The results of this study show that ventilating air flows can be increased significantly during periods of constant train motion and acceleration, by factors of 1.4 and 2 respectively, but that the train drag will increase at the same rate. During deceleration negligible increases in ventilation flows are found but drag increases by a factor of 4.
AB - In order to ensure the safety and comfort of passengers and staff, an underground railway requires an extensive ventilation and cooling system. One mechanism for underground railway ventilation is the movement of air induced by trains, termed the 'piston effect'. This study investigated the effect of altering the blockage ratio of an underground train upon the ventilating air flows driven by a train. First a computational model was developed and validated with experimental data from literature. This model was scaled to represent an operational underground railway with high blockage ratio and the blockage ratio varied to evaluate the effects upon ventilation. The results of this study show that ventilating air flows can be increased significantly during periods of constant train motion and acceleration, by factors of 1.4 and 2 respectively, but that the train drag will increase at the same rate. During deceleration negligible increases in ventilation flows are found but drag increases by a factor of 4.
KW - aerodynamics
KW - computational fluid dynamics
KW - high blockage ratio
KW - underground railways
KW - ventilation
UR - https://www.sciencedirect.com/journal/journal-of-wind-engineering-and-industrial-aerodynamics
U2 - 10.1016/j.jweia.2015.09.004
DO - 10.1016/j.jweia.2015.09.004
M3 - Article
AN - SCOPUS:84943556577
VL - 146
SP - 195
EP - 206
JO - Journal of Wind Engineering and Industrial Aerodynamics
JF - Journal of Wind Engineering and Industrial Aerodynamics
SN - 0167-6105
ER -