High-viscosity biphasic flow characterization in a pipeline: application to flow pattern classification and leak detection

Pipeline systems play an essential role in the oil industry. These systems connect ports, oil fields, refineries, and consumer markets[104]. Pipelines covering long distances require pumping stations, where products are propelled to the next pumping station, refinery, or deposit terminal, thus traveling through most of the country. The product considered in this research work is crude oil. It is usually transported with a combination of crude oil with viscosity reducers (DRA, drag reducer agent) and oil with gas in onshore/offshore pipelines. This mode of transport is efficient for large quantities and large product shipment distances. Problems may arrive when a leak occurs. In major incidents, large scale damage to humans and the environment is possible. Then, this research addresses the problem of how to detect the leak earlier to reduce the impact in the surrounding areas and economic losses, considering five research topics taking into account that the products inside the pipeline are water-glycerol and gas-glycerol mixtures (simulating oil-DRA and oil-gas in the laboratory test apparatus). The first research topic presents a mathematical model to describe the flow of a mixture of water and glycerol in pressurized horizontal pipelines, which emulates the mixture of heavy oil and a viscosity reducer. The model is based on the mass and momentum conservation principles and empirical correlations for the mixture’s density and viscosity. The set of partial differential equations is solved using finite differences. These equations were implemented in a computer platform to be able to simulate a system. This simulation platform is a tool to simulate leak cases for different fractions of water and glycerol to evaluate algorithms for leak detection and localization before their implementation in a laboratory setting.DoctoradoDoctor en Ingeniería Mecánic

Modeling and control of a robot manipulator using standard control techniques and H infinity

Se presenta el diseño de un control estándar basado en la norma H2 y de un control H-infinito aplicados en un manipulador de dos grados de libertad. El manipulador se modeló con las ecuaciones de Euler-Lagrange y la función de disipación de Rayleigh. Se utilizó un modelo en el Toolbox SimMechanics exportando la geometría y propiedades físicas desde SolidWorks. Los resultados demuestran que la respuesta transitoria en el control H infinito es más suave que en el control estándar.This paper presents the design of a standard control based on the H2 standard and an H-infinity control applied in a manipulator of two degrees of freedom. The manipulator was modeled with the Euler-Lagrange equations and the Rayleigh dissipation function. A model was used in the SimMechanics Toolbox by exporting geometry and physical properties from SolidWorks. The results obtained show that transient response in H infinity control is smoother than the standard control