城镇居民用户天然气异常流量识别  

Identification of Abnormal Natural Gas Flow Rates for Urban Residential Users

作　　者：刘兴伟 黄建安 陈婷婷 王凡 王铁强 柴家凤[2] 孙俊芳 沃龙[1,2] LIU Xingwei;HUANG Jianan;CHEN Tingting;WANG Fan;WANG Tieqiang;CHAI Jiafeng;SUN Junfang;WO Long

机构地区：[1]北京市燃气集团研究院,北京100011 [2]北京市燃气集团有限责任公司,北京100035

出　　处：《煤气与热力》2024年第8期V0020-V0024,共5页Gas & Heat

摘　　要：分析户内天然气泄漏异常流量,结合燃气泄漏流量、用户房间容积和换气次数建立燃气泄漏时间计算模型。搭建测试平台,分析不同供气压力下胶管前端脱落、后端脱落时流量变化,给出异常流量识别实施策略。评估燃气泄漏后达到爆炸下限的时间时,需要考虑燃气泄漏流量、房间换气次数、房间容积。不同位置胶管脱落,胶管脱落流量均随供气压力增加而变大。相同的供气压力条件下,前端脱落的胶管脱落流量大于后端脱落。设定切断值采用燃气表最大流量的1.2倍,存在较多漏判。根据智能燃气表是否具有压力监测模块及用户供气压力,采用不同的异常流量识别策略。当智能燃气表具有压力监测功能时,可以通过流量与压力关系式计算,得到切断值。当智能燃气表无压力监测功能时,建议切断值设定为1.1倍的用户燃具额定最大负荷流量,同时,设定自闭阀在压力小于等于1 kPa时动作,切断供气。The abnormal flow rate of indoor natural gas leakage is analyzed,and the calculation model for gas leakage time is established by combining the flow rate of gas leakage,the volume of the user's room and the air exchange rate.A testing platform is built to analyze the flow rate changes when the front and rear ends of the rubber hose are detached under different gas supply pressures,and provide implementation strategies for identifying abnormal flow rates.When evaluating the time to reach the lower explosive limit after gas leakage,it is necessary to consider the gas leakage flow,the air exchange rate of room and the room volume.The hose detachment at different positions and the flow rates of hose detachment both increase with the increase of gas supply pressure.Under the same gas supply pressure conditions,the flow rate of hose detachment at the front end is greater than that at the rear end.The cut-off value is set at 1.2 times the maximum flow rate of the gas meter,which has many omissions.Different abnormal flow identification strategies are adopted based on whether the intelligent gas meter has a pressure monitoring module and the user's gas supply pressure.When the intelligent gas meter has pressure monitoring function,the cut-off value can be calculated through the relationship between flow rate and pressure.When the intelligent gas meter does not have pressure monitoring function,it is recommended to set the cut-off value to 1.1 times the rated maximum load flow rate of the user's gas appliances,and set the self-closing valve to operate when the pressure is less than or equal to 1 kPa to cut off the gas supply.

关 键 词：异常流量 换气次数 胶管脱落 燃气泄漏流量 

分 类 号：TU996.7[建筑科学—供热、供燃气、通风及空调工程]