Analytical investigation of the influence of natural gas leakage & safety zone in a pipeline flow
Abhishek Agarwal, Olefile Bethuel Molwane, I. Pitso
Abstract
Natural gas transportation is complex process which involves building long pipelines with various diversions and joints. Sometimes due to environmental factors like moisture, humidity cracks do initiate causing pipelines to rupture. Such ruptures result in natural gas leakage causing risks of infestations and fire due to methanation reaction. The current research investigates the effect and zone of influence of natural gas leakage from pipeline using techniques of Computational Fluid Dynamics. The CAD model is developed in ANSYS design modeller and CFD analysis is conducted using ANSYS CFX software. The mass fraction and pressure variations in ambient zone depicted the zone of influence of leakage and also specifies the safety zone of operation. The analysis is conducted for three different external air velocities i.e. 5 m/s, 10 m/s and 20 m/s and the combustion model used for analysis is eddy dissipation. The analysis has shown that external air velocity has significant effect on gas leakage zone which increased with increase in external air velocity. The leakage zone was deflected towards windward direction. It is recommended that during any such leakage, the staff personnel should maintain a minimum distance of 0.2 m away from leakage zone to avoid any infestation.