Numerical simulation on prediction model of risk range of typical gas release through small holes

Abstract

In order to relieve the shortage of petroleum resources, it is a reasonable way to develop synthetic oil industry as a supplement of petroleum resources. In chemical synthesis, most reactions need to be carried out in pressurized environment. Leakage is one of the most common accidents, and the research of gas leakage in pressurizing device and pipeline is still to be improved. Therefore, by CFD numerical simulation method, this paper takes common gases (H2, CO, CH4) in chemical synthesis as the research object, and uses the range of dangerous concentration after gas leakage as the danger range of gas leakage. Fluent software is used to simulate gas leakage and diffusion under different working conditions. In order to study the gas leakage diffusion law and leakage danger range under different gas, different leakage pressure, different leakage temperature and different leakage port diameter, and build the prediction model of leakage danger range. The results show that the danger range of gas leakage increases with the increase of leakage pressure when other factors remain unchanged. With the increase of gas temperature, the danger range of gas leakage decreases obviously. With the increase of the diameter of the leakage port, the danger range of gas leakage increases obviously. Among the three variables, the increase of leakage port size has the most obvious effect on the expansion of the danger range. When the gas leakage pressure increases from 1 MPa to 2 MPa, the danger range of three kinds of gas leakage increases by about 10%. When the gas temperature increases from 300 K to 400 K, the danger range of three kinds of gas leakage also increases by about 10%, and when the diameter of the leakage port increases from 2 mm to 3 mm, the danger range of three kinds of gas leakage increases by 50%. By quantitative analysis of the length and width data of the leakage danger range in the numerical simulation results of three kinds of gases (H2, CO, CH4), and dimensionless treatment of the parameters, the prediction models of the leakage danger range (length and width) of three kinds of gases (H2, CO, CH4) are finally obtained. The length and width of the leakage danger range are functions of pressure ratio and temperature ratio. The prediction results can provide reference for the rescue and emergency treatment of leakage accidents.

Keywords

• chemical synthesis
• gas leakage
• cfd
• scope of danger
• predictive models