综合管廊燃气舱燃气泄漏安全响应研究

Study on security response of gas leakage in gas cabin of utility tunnel

通过Fluent数值模拟及实验结果验证的方法,对于管廊内燃气泄漏后的安全响应问题进行分析研究。结果表明:当管廊发生燃气泄漏,燃气报警器响应时,启动事故通风并降低管道压力至0.4 MPa,通风150 s后可进行在线修补;设定管道的切断浓度为爆炸下限的45%,若报警器处浓度低于切断浓度,则继续进行事故通风并降低管道压力至0.08 MPa,150 s后可进行在线修补;若报警器处浓度高于切断浓度,则紧急切断,通风310 s后可进行管道修补。

The security response after gas leakage in the utility tunnel was analyzed and studied by simulation based on Fluent and verified by experiment.The results show that when gas leakage occurs in the utility tunnel and the gas detector alarms,the ventilation system is started and the pipeline pressure is reduced to 0.4 MPa.It can be repaired online after 150 s ventilation;if the concentration of alarm is lower than the cut-off concentration with the cut-off concentration set to be 45%of the lower explosive limit,the pipeline pressure will continue to be reduced to 0.08 MPa,and the pipeline pressure will be repaired on-line after 150 s of ventilation;if the concentration of the alarm is higher than the cut-off con⁃centration,the emergency cut-off will be carried out.The pipeline will be repaired after ventilation for 310 s.