Multiphase flow reconstruction in oil pipelines by capacitance tomography using simulated annealing
A highly optimized simulated annealing (SA) algorithm is applied to reconstruct permittivity images of real two-phase gasoilflows through a cylindrical vessel using electrical capacitance tomography (ECT). ECT yields low-accuracy images but isrobust, inexpensive and much faster than many other tomog...
| Autores: | , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2005 |
| País: | México |
| Institución: | Instituto Mexicano del Petróleo |
| Repositorio: | Redalyc-IMP |
| OAI Identifier: | oai:redalyc.org:56844303 |
| Acceso en línea: | https://www.redalyc.org/articulo.oa?id=56844303 |
| Access Level: | acceso abierto |
| Palabra clave: | Ciencias de la Tierra image reconstruction finite volume method Capacitance tomography very fast simulated annealing |
| Sumario: | A highly optimized simulated annealing (SA) algorithm is applied to reconstruct permittivity images of real two-phase gasoilflows through a cylindrical vessel using electrical capacitance tomography (ECT). ECT yields low-accuracy images but isrobust, inexpensive and much faster than many other tomography processes. This non-intrusive method essentially measures nonconductivesystem distributions and is applied in oil industry processes such as mixing or stirring vessels, fluidized bed reactors,separator tanks and pipelines carrying multiphase flows.A forward problem is solved at each step of an iterative algorithm to solve the inverse problem using simulated annealing(SA). Comparisons with linear methods like The Projected Landweber technique are discussed. In this paper we introduce a finitevolume discretization with local mesh refinements in a cylindrical configuration close to the electrodes in order to improveresolution in the calculation of capacitances, and to avoid problems with resolution at the centre of cylindrical container whenfinite differences are used. This discretization has the advantage of a conservative formulation as used in finite element methodsand features the flexibility of mesh refinement close to the electrodes. Thus, improvement of local accuracy is achieved withoutincreasing prohibitively the number of mesh points. Performance of the forward problem resolution is compared with finiteelement based methods and experimental data. We show that the non linear version of SA provides better reconstructions of threephaseflows than the Landweber method. |
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