通过建立一个简化的数学模型,分析了喷淋作用时烟气的运动情况,在理论上给出了影响自然排烟效率的主要因素.通过一组喷淋与自然排烟作用实验,进一步探讨喷淋对自然排烟效率的影响.结果表明,自然排烟的效率取决于烟气层的厚度与烟气层温度.水喷淋作用后,烟气温度显著降低,自然排烟口的烟气溢出速度大大减小.对于顶部排烟的情况,当喷淋压力在0.15 MPa以下时,烟气溢出速度是未设置喷淋时的65%左右.烟气层厚度对自然排烟效率也有着重要的影响,在烟气厚度层很大的情况下,大压力喷淋作用下烟气的溢出速度有可能比小压力喷淋作用时大一些.
A simple model was built to study smoke movement under spray and venting. The parameters affecting efficiency of natural venting were presented. To better understand efficiency of venting under water spray, a series of experiments were carried out. The results show that efficiency of natural venting is decided by thickness and temperature of smoke layer. Under water spray, temperature decreases apparently and efficiency of natural venting is only 65% that of venting without water spray. Smoke layer temperature also has great effect on efficiency of natural venting. In some cases, smoke emitting velocity under water spray with high working pressure may be higher than that under water spray with low working pressure.