L型电缆廊道火灾温度场及烟气蔓延模拟

Temperature field and smoke flow of fire in L-type cable tunnel

通过对L型电缆廊道火灾温度场及烟气蔓延的数值模拟,研究不同位置起火情况下温度分布特性和烟气层厚度的变化规律。2段15.0 m×2.5 m×3.0 m的电缆廊道呈90°连接,两侧布置结构为8层的电缆桥架,桥架宽0.6 m,层间距0.2 m。通过抽取拐点温度和烟气层厚度的数据信息,分析火源高度和纵向风速对L型廊道拐角结构烟气蔓延的影响。使拐点烟气层厚度最大的风速约为1.0~1.1 m/s。结合烟气流场的模拟结果,指出L型廊道拐点处存在明显的"蓄烟效应",并有增大火灾的趋势。

Based on the numerical simulation of fire temperature field and smoke flow of fire in L-type cable tunnel, the variation law of fire temperature field and smoke thickness was studied. The two cable tunnels of 15.0 m × 2.5 m × 3.0 m were connected vertically with 8 layers of cable trays on both sides. The width of cable tray was 0.6 m and the distance between the trays was 0.2 m. By analyzing the data of inflection point temperature and the thickness of smoke layer, the influence of fire source height and longitudinal wind speed on the flue gas spread of corners of corridor were analyzed. The wind speed of 1.0-1.1 m/s led to the biggest thickness of smoke layer at inflection point. Combining with the above research results, there was obvious ＂smoke accumulating effect＂ at the inflection point, which was a tendency to increase the fire.