Effects of Pipeline Pressure on Diffusion Characteristics of Leaked Natural Gas in Tunnel Space.

Pipeline transportation has become the main mode of natural gas transportation. Due to inevitable aging, corrosion, and third-party damage, natural gas pipeline leakage accidents occur frequently. Leakage in the tunnel will lead to the leakage and accumulation of natural gas, and the potential explosion risk will threaten the tunnel's safety.

Study on Gas Diffusion in Fire Working Areas of Oil and Gas Pipelines Based on Temperature Difference.

When a pipeline is under fire safety work construction, the stack effect of the pipeline will increase the diffusion rate of nitrogen, reduce the oxygen content, and cause asphyxia. To prove the influence of the stack effect of the pipeline on the nitrogen movement in the pipeline and put forward effective ventilation control measures, the formation mechanism, gas diffusion law, and ventilation parameters of the stack effect of the oil and gas pipelines are studied through theoretical derivation and numerical simulation. The results show that the nitrogen concentration at the height of the breathing zone in the hot zone first increases and then decreases along the axial distance.

Research on Control of Ore Pass Dust by Unloading Time Interval and Foam Control Technology.

To control the dust pollution caused by the unloading of a multilevel ore pass, numerical simulation and similar experiments were carried out to study the airflow and dust migration influenced by the unloading quantity and the continuous unloading at different time intervals in the ore pass. From this research, the following conclusions are drawn: when the first level of the ore pass is unloaded, the third and fourth levels are the main dust-producing positions, and the concentrations of dust in the breathing zone can reach 85 and 325 mg/m, respectively. Increasing the unloading interval and reducing the total single unloading quantity can prevent the superposition of dust production.