Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
NUMERICAL STUDY OF FLAMMABLE GASES DISPERSION IN OIL PLATFORMS
Submission Author:
Thiago Gonsalves , RJ
Co-Authors:
Thiago Gonsalves, Eduardo Braga, Angela Nieckele, Wellington Campos
Presenter: Thiago Gonsalves
doi://10.26678/ABCM.COBEM2021.COB2021-2269
Abstract
Activities of oil exploration and production in Onshore and Offshore structures are associated with an imminent risk of gas or oil leakage, which, encountering any kind of ignition, can cause fires and explosions, having the potential to cause substantial financial losses and deaths. In view of the accidents with the P-36 platform in 2001, in the Campos Basin, and with Piper Alpha in 1988, in the North Sea, which caused great financial damage and loss of several lives, robust gas detection systems are being considered in offshore systems projects. To assist in the collection of accurate information for risk analysis, computational fluid dynamics (CFD) is an excellent tool, which allows anticipating possible risk occurrences, due to its ability to simulate various situations that would be extremely laborious to reproduce experimentally. In the present work, CFD analysis was performed to analyze the leakage of natural gas from a leakage point located in the gas compression module at an offshore platform. The actual layout of the FPSO (Floating, Production, Storage, and Offloading), as well as the environmental conditions, were considered. The 3D geometry model was obtained with ANSYS tool ICEM. The flow turbulence was modeled with the RANS methodology employing the two-equation κ-ε model. The transport equations of mass, momentum, energy, and turbulent quantities were numerically determined with ANSYS CFX. In order to verify the interaction of the clouds formed with the structures of the unit, 8 cases of gas leaks were simulated in steady-state, in which two wind intensities were considered: 0.5 m/s representing the calm condition, and 6.5 m/s representing the highest speed ever recorded. From the simulation results, critical spots were identified. The volume of the cloud was determined for each scenario and subsequently an equivalent TNT calculation was performed, in order to identify potential risks of the offshore structure in the event of ignition of the dispersed gaseous material.
Keywords
Gas dispersion, CFD, Equivalent TNT
