CFD Analysis of Cavitation in a Crude Oil Pipeline to an Oil Tanker

Abstract

Emission of volatile organic compounds (VOCs) during loading crude oil to oil tankers has become a particularly critical issue because it does not only cause environmental problems but also economic loss. Since a pipeline from a terminal to an oil tanker has a long vertical drop line, the acceleration of the pipe flow by the gravity may cause a sudden pressure drop that stimulates cavitation, the evaporation of the VOCs in crude oil. To analyze the amount of vaporized VOCs and the fluid dynamic behaviors of the two-phase pipe flow, experiments have been conducted with a pilot-scale pipeline and a computational fluid dynamic (CFD) model have been developed based on the experimental result. As crude oil is the complex mixture of various hydrocarbons, a phase transition model based on crude oil assay data has been developed and included in the CFD model. This developed model is capable of predicting the amount of vaporized VOCs and the fluid dynamic behaviors of the pipe flow with different operating conditions, e.g. flow rate, pump pressure, type of crude oil, etc. Thus, it is expected that the model will contribute to analyzing the amount of VOC emission during loading crude oil onto an oil tanker. © 2012 Elsevier B.V.