基于PID方法的倾斜隧道中火灾烟气控制数值模拟

Numerical simulation on control of fire smoke in inclined tunnels based on the PID method

为改善激活式射流风机对隧道火灾烟气控制的灵活性,采用比例-积分-微分(PID)控制方法实现对倾斜隧道中火灾烟气的自动化控制.数值求解了倾斜隧道中火灾烟气的蔓延,并耦合PID控制算法控制通风速度以模拟自动控制的射流风机.数值结果表明:在参数调整完毕后,在该数值模拟的条件下,对于非定常功率的火源、倾角大范围变化的情况,PID通风控制系统依然可以实现对倾斜隧道中火灾烟气的良好控制;PID通风控制系统对控制距离的变化较敏感,控制距离与系统启动时间呈二次指数变化关系,与系统达到准稳态所需时间呈正比关系;增加PID控制系统的定点清零功能有助于减少对火灾烟气控制的延迟.

In order to improve the flexibility of activated jet fans in controlling tunnel fire smoke,the proportional-integral-differential(PID)control method was adopted to realize the automatic control of fire smoke in inclined tunnels.The spread of fire smoke in inclined tunnel was numerically solved,and the ventilation velocity was self-adaptively updated by coupling the PID control algorithm to simulate the automatic control of the jet fans.The numerical results show that,under the specified conditions of numerical simulation,the PID ventilation control system can still achieve excellent control over the spread of fire smoke in the tunnel for unsteady release power of fire source and for the inclination angle in a large range.The PID ventilation control system is sensitive to the control distance in that the control distance has a quadratic exponential relationship with the start-up time of the ventilation control system,and is proportional to the time required for the temperature at the detection site to reach the quasi-steady state.Adding the function of clearing data under specific conditions is helpful to reduce the delay of fire smoke control.