| Title |
Comparative Analysis of Flow Characteristics Using Reflected Pressure Wave at Crossing of Subway Trains in Straight Tunnel |
| Authors |
Deuksun Lee ; Jungmin Cho ; Myeongho Lee ; Jaeyong Sung |
| DOI |
https://doi.org/10.6110/KJACR.2018.30.3.123 |
| Keywords |
열차의 교차 ; 반사압력파 ; 압력구배 ; 전단유동 Crossing of trains ; Reflected pressure wave ; Pressure gradient ; Shear flow |
| Abstract |
In this study, CFD is used to compare and analyze the flow characteristics using reflected pressure wave during the intersection of two trains in straight tunnel. Two tunnels of different lengths; 600 m and 3,400 m were designed and numerical analysis of the flow characteristics of two tunnels carried out by setting the crossing state of the two trains at a constant velocity of 27 m/s form the center of the tunnel. The simulation model was designed using the actual tunnel and subway dimensions The train motion was achieved by using the moving mesh method. For the numerical analysis, k-ω standard turbulence model and an ideal gas were used to set the flow conditions of three-dimensional, compressible and unsteady state. In the analysis results, it was observed that the inside of the long tunnel without interference of the reflected pressure wave was maintained at a pressure lower than the atmospheric pressure and that the flow direction was determined by the pressure gradient and shear flow. On the other hand, the flow velocity in the short tunnel was faster and the pressure fluctuation was noted to have increased due to the reflected pressure wave, with more vortices formed. In addition, the flow velocity was noted to have changed more irregularly. |