回风大巷内示踪气体测试矿井外部漏风率的最短采样检测距离研究

针对示踪气体法测试回风立井型矿井外部漏风率过程中由于回风大巷的示踪气体采样检测有效长度有限可能会导致示踪气体无法准确采样检测的问题，以纳林河二号矿井一号回风立井和二号回风立井回风大巷为研究对象，制定了多回风巷型回风立井外部漏风率示踪气体法测试方案，在此基础上，分别采用理论公式法和CFD数值模拟方法计算了各回风大巷的SF6气体最短采样检测距离，理论公式法计算结果显示一号回风立井和二号回风立井均不宜采用示踪气体法测试矿井外部漏风率，CFD数值模拟方法计算结果与之相反。现场实测结果显示通过CFD数值模拟法确定的回风大巷最短采样检测距离处巷道断面内SF6气体分布均达到均匀分布状态，CFD数值模拟法计算结果的准确明显大于理论公式法，研究表明采用CFD数值模拟法计算示踪气体最短采样检测距离能够对回风立井型矿井外部漏风率示踪气体测试法的现场适用性进行科学准确地论证。

The calculation of the shortest sampling detection distance of the tracer gas in the return air roadway during the test of external air leakage rate of the mine

In order to solve the problem that in the process of measuring the external air leakage rate of return shaft type mine by tracer gas method, the limited length of the main return air roadway may lead to the inaccuracy of tracer gas sampling and detection,Taking the No.1 return air shaft and No.2 return air shaft of nalinhe No.2 mine as the research object, the test scheme of tracer gas method for the external air leakage rate of multiple return air shaft was established. On this basis, the shortest sampling distance of SF6 gas in each main return air roadway was calculated by theoretical formula method and CFD numerical simulation method respectively. The calculation results of theoretical formula method showed that the tracer gas method was not suitable for measuring the external air leakage rate of No.1 return air shaft and No.2 return air shaft, and the result of CFD numerical simulation were opposite. The field measurement results showed that the SF6 gas distribution in the roadway section at the shortest sampling distance of the return air roadway determined by the CFD numerical simulation method was uniform, and the accuracy of the CFD numerical simulation method was significantly greater than that of the theoretical formula method. The research showed that calculating the shortest sampling distance of the tracer gas by the CFD numerical simulation method could be used to demonstrate scientifically and accurately field applicability of the external air leakage rate of return shaft type mine by tracer gas method.