Escoamento não isotérmico de óleo pesado, água e gás em duto vertical com vazamento.

Abstract

Leakage monitoring system should be able to detect and locate a leak within minutes, therefore, to reduce or to prevent environmental accidents, and contributing significantly to an operational safety. When a leak occurs in a pipeline a pressure wave will propagate through the pipeline, upstream and downstream relatively to the leak position. Therefore is important to determine and understand the flow characteristics inside the duct in each instant of time, detecting the leak and preventing the generating false alarms. In this sense, this paper aims to present a numerical simulation of multiphase flow (oil, water and gas) in pipeline with and without leaks using the commercial code ANSYS CFX 12.0. Are evaluated different parameters such as oil viscosity, initial velocity of oil and gas phases, volume fraction of phases, the magnitude of the leak and their effects on the flow are appraised. Results as transient total pressure, velocity, volume fraction, and streamlines are presented and analyzed. It was found that the transient pressure is sensitive to characteristics of thermal hydrodynamic fluid. The increase in magnitude of the leak increases the pressure drop value and reduce the value of the pressure recovery in pipe. Large quantities of gas present in the flow can decrease the magnitude of pressure drop, and generate large oscillations in it.