Maximum temperature rise is an important parameter in tunnel fires. It is noted that classical models of maximum temperature rise in previous studies are limited to single tunnel. However, in real situations, there is cross-passage between two neighboring tunnels. The studies about the effect of distance between fire source and cross-passage on the temperature rise is limited. In this study, numerical simulations on the maximum temperature rise of ceiling jet flow in tunnel fires under longitudinal ventilation with various distances (L_f) between fire source and cross-passage are conducted by using FDS for a cross angle of 30°. Results show that maximum temperature rise decreases with either the increasing of longitudinal ventilation velocity or the decreasing of heat release rate. The cross-passage has an effect on the fire plume flow velocity under the ceiling, which further affects the maximum temperature. For small ventilation velocities (1 m/s and 2 m/s), the maximum temperature rise is much lower than that of a single tunnel without cross-passage, and there is no significant difference between various L_f. For large ventilation velocities (3 m/s and 4 m/s), the maximum temperature rise decreases with the increasing of L_f from 0 to 4.5 m, and for ${\mathit{\text{L}}}_{\mathit{\text{f}}}>4.5$ m, the maximum temperature rise has no significant change anymore. It is noted that for the large ventilation velocities, the maximum temperature rise of L_f = 0 is close to that of a single tunnel without cross-passage. The effect of cross angle on the maximum temperature rise is also researched which shows that maximum temperature rise increases with the increasing of cross angle. A correlated model is proposed to predict the maximum temperature rise by taken L_f into account.

最大温度升高是隧道火灾中的重要参数。需要注意的是，先前研究中最大温升的经典模型仅限于单隧道。但是，在实际情况中，两条相邻的隧道之间存在交叉通道。关于火源与交叉通道之间的距离对温度升高的影响的研究是有限的。在这项研究中，在不同距离（L _f）的纵向通风条件下，隧道火灾中天花板射流的最大温度升高的数值模拟使用FDS在30°的交叉角处进行火源和交叉通道之间的）。结果表明，最大温度升高随纵向通风速度的增加或放热率的降低而减小。交叉通道会影响天花板下方的火焰羽流速度，进而影响最高温度。对于较小的通风速度（1 m / s和2 m / s），最大温升比没有交叉通道的单个隧道的温升要低得多，并且各个L _f之间没有显着差异。对于较大的通风速度（3 m / s和4 m / s），随着L _f从0增加到4.5 m，最大温度上升减小，而对于${\mathit{\text{大号}}}_{\mathit{\text{F}}}>4.5$m，最大温升不再有明显变化。注意，对于较大的通风速度，L _f  = 0的最大温升接近没有交叉通道的单个隧道的温升。研究了交叉角对最大温升的影响，表明最大温升随交叉角的增加而增加。提出了一个相关模型，通过考虑L _f来预测最大温度上升。