火源功率对竖井负压控烟效果影响的实验研究

基于竖井的烟囱效应原理,利用小尺寸实验台开展了一系列实验,通过改变油盘的尺寸,对竖井内的烟气温度、压力、速度以及通风口处的压力、气流速度进行测量,研究了火源功率对房间利用竖井进行负压控烟效果的影响。实验结果表明:一方面随着火源功率的增大,室内温度升高,热烟气形成的热压增大,使烟气向外膨胀;另一方面,竖井底部的烟气温度升高,竖井底部的负压值增大,烟囱效应增强,排烟速度增大,新鲜空气补入的速度增大,逐渐抑制住烟气从通风口向外溢出,达到了负压控烟的效果。

Influence of fire source on the negative pressure smoke control by shaft stack effect: Experimental studies

Based on the principle of stack effect, a set of experiments were carried out by varying the pool size in a small scaled configuration, and the effect of the fire power on smoke control in the room using a shaft was studied. The temperature, pressure, velocity in the shaft, as well as the pressure and velocity in the vent were measured and studied. Results showed that with the increase of fire power, the temperature in the room and the pressure produced by hot smoke increased, making the smoke expands outward. On the other hand, the temperature and the negative pressure at the bottom of shaft increased, with enhancement of stack effect, and the increase of the smoke velocity and the velocity in the vent, inhabiting the smoke overflow from the fire room gradually. By these effects, the smoke can be successfully controlled by negative pressure.