Numerical simulations are conducted to study the influence of the heat release rate, the fire source location, and the tunnel slope on the smoke spread characteristics of V-shaped slope tunnels. Theoretical analysis and simulation results show that the smoke movement in the V-shaped slope tunnel is affected by the competition effect on both sides, which leads to the fact that the smoke only overflows from the tunnel portal closer to the fire source, and a large amount of air flows into the tunnel from the other portal. Due to the competition effect, the downstream smoke back-layering length first decreases and then increases slightly with the increasing distance between the fire source and the grade change point (refering to the intersection point of two adjacent slope lines). As the tunnel slope increases, both the back-layering length and the influence of the fire source location on the smoke spread decrease gradually. Besides, the heat release rate has little effect on the smoke movement characteristics. Based on the back-layering length and the mass flow rate distribution, the smoke movement behaviors in the V-shaped tunnel can be divided into the double-slope control zone, the transition zone, and the single-slope control zone. When the vertical distance between the fire source and the grade change point is more than 2.1 m, the smoke movement can be classified in the single-slope control zone. The mass flow rate reaches the peak value when the fire source is located in the transition zone, and the dimensionless mass flow rate is proportional to the tunnel slope and the 0.3 power of the dimensionless heat release rate.

通过数值模拟研究了热释放速率、火源位置、隧道坡度对V型坡隧道烟气蔓延特性的影响。理论分析和模拟结果表明，V形斜坡隧道内的烟气运动受两侧竞争效应的影响，导致烟气仅从靠近火源的隧道洞口溢出，产生大量大量空气从另一个入口流入隧道。由于竞争效应，随着火源与坡度变化点（指相邻两条坡度线的交点）距离的增加，下游烟气背层长度先减小后略有增加。随着隧道坡度的增加，背层长度和火源位置对烟气蔓延的影响均逐渐减小。此外，放热速率对烟气运动特性影响不大。根据背层长度和质量流量分布，V形隧道内的烟气运移行为可分为双坡控制区、过渡区和单坡控制区。当火源与坡度变化点的垂直距离大于2.1m时，烟气运动可归入单坡控制区。当火源位于过渡带时，质量流量达到峰值，无量纲质量流量与隧道坡度和无量纲放热率的0.3次方成正比。