The progressing cavity pump is a type of positive displacement pump that is capable of moving nearly any fluid. This type of pump transports fluids in a series of discrete cavities formed by the helical geometries of its rigid rotor and elastomeric stator. With appropriate materials for the rotor and stator, this pump can move combinations of liquids, suspended solids, and gasses equally well. Because of its versatility, the progressing cavity pump is widely used in the oil industry to transport mixtures of oil, water, and sediment; this investigation was prompted by a desire to extend the use of progressing cavity pumps to wet gas pumping applications. One of the progressing cavity pump's limitations is that the friction between the rotor and stator can generate enough heat to damage the rotor if the pump is not lubricated and cooled by the process fluid. Conventional wisdom dictates that this type of pump will overheat if it pumps only gas, with no liquid in the process fluid. If a progressing cavity pump is used to boost the output from a wet gas well, it could potentially be damaged if the well's output is too dry for an extended period of time. This project seeks to determine how a progressing cavity pump behaves when operating at gas volume fractions between 0.90 and 0.98. A progressing cavity pump manufactured by seepex, model no. BN 130-12, is tested at half and full speed using air-water mixtures with gas volume fractions of 0.90, 0.92, 0.94, 0.96, and 0.98. The pump's inlet and outlet conditions are controlled to produce suction pressures of 15, 30, and 45 psi and outlet pressures 0, 30, 60, 90, 120, and 150 psi higher than the inlet pressure. A series of thermocouples, pressure transducers, and turbine flow meters measures the pump's inlet and outlet conditions, the flow rates of water and air entering the pump, and pressures and temperatures at four positions within the pump's stator. Over all test conditions, the maximum recorded temperature of the pump stator did not exceed the maximum safe rubber temperature specified by the manufacturer. The pump’s flow rate is independent of both the fluid's gas volume fraction and the pressure difference across the pump, but it increases slightly with the pump's suction pressure. The pump's mechanical load, however, is dependent only on the pressure difference across the pump and increases linearly with that parameter. Pressure measurements within the stator demonstrated that the leakage between the pump's cavities increases with the fluids gas volume fraction, indicating that liquid inside the pump improves its sealing capability. However, those same measurements failed to detect any appreciable leakage between the two pressure taps nearest the pump's inlet. This last observation suggests that the pump could be shortened by as much as 25 percent without losing any performance in the range of tested conditions; shortening the pump should increase its efficiency by decreasing its frictional mechanical load.

Made available in DSpace on 2014-12-17T14:58:16Z (GMT). No. of bitstreams: 1 VictorWFA_DISSERT.pdf: 4406666 bytes, checksum: 17531cab6caf785a3e82578d15d0e5d9 (MD5) Previous issue date: 2012-11-05 / The progressing cavity pumping (PCP) is one of the most applied oil lift methods nowadays in oil extraction due to its ability to pump heavy and high gas fraction flows. The computational modeling of PCPs appears as a tool to help experiments with the pump and therefore, obtain precisely the pump operational variables, contributing to pump s project and field operation otimization in the respectively situation. A computational model for multiphase flow inside a metallic stator PCP which consider the relative motion between rotor and stator was developed in the present work. In such model, the gas-liquid bubbly flow pattern was considered, which is a very common situation in practice. The Eulerian-Eulerian approach, considering the homogeneous and inhomogeneous models, was employed and gas was treated taking into account an ideal gas state. The effects of the different gas volume fractions in pump volumetric eficiency, pressure distribution, power, slippage flow rate and volumetric flow rate were analyzed. The results shown that the developed model is capable of reproducing pump dynamic behaviour under the multiphase flow conditions early performed in experimental works / O bombeio por cavidades progressivas (BCP) ? um dos m?todos de eleva??o artificial mais utilizados atualmente pela ind?stria do petr?leo devido ? sua capacidade de atuar em reservat?rios de ?leos pesados e com elevada fra??o de g?s. A modelagem computacional de BCPs surge como uma ferramenta para auxiliar os experimentos com a bomba e assim obter com precis?o as suas vari?veis de opera??o, o que contribui para a otimiza??o do projeto e da opera??o da bomba na situa??o a qual se encontra. Um modelo computacional do escoamento multif?sico no interior de uma BCP de estator met?lico que considera o movimento relativo entre o rotor e o estator foi desenvolvido no presente trabalho. Em tal modelo, o escoamento g?s-l?quido no padr?o de bolhas foi considerado, o que ? uma situa??o muito comum na pr?tica. A abordagem Euleriana- Euleriana, considerando o modelo homog?neo e n?o-homog?neo, foi empregada e o g?s foi tratado levando em considera??o um estado de gas ideal. Os efeitos das diferentes fra??es de g?s na efici?ncia da bomba, distribui??o de press?o, pot?ncia, taxa de escorregamento e vaz?o volum?trica foram analisados. Os resultados mostraram que o modelo desenvolvido ? capaz de reproduzir o comportamento din?mico da BCP sob as condi??es de escoamento multif?sico previamente realizados em trabalhos experimentais

Made available in DSpace on 2014-12-17T14:54:48Z (GMT). No. of bitstreams: 1 BennoWA.pdf: 2840837 bytes, checksum: 9aeb78caaab0d5311260d71632eb20e8 (MD5) Previous issue date: 2008-02-08 / The progressing cavity pump artificial lift system, PCP, is a main lift system used in oil production industry. As this artificial lift application grows the knowledge of it s dynamics behavior, the application of automatic control and the developing of equipment selection design specialist systems are more useful. This work presents tools for dynamic analysis, control technics and a specialist system for selecting lift equipments for this artificial lift technology. The PCP artificial lift system consists of a progressing cavity pump installed downhole in the production tubing edge. The pump consists of two parts, a stator and a rotor, and is set in motion by the rotation of the rotor transmitted through a rod string installed in the tubing. The surface equipment generates and transmits the rotation to the rod string. First, is presented the developing of a complete mathematical dynamic model of PCP system. This model is simplified for use in several conditions, including steady state for sizing PCP equipments, like pump, rod string and drive head. This model is used to implement a computer simulator able to help in system analysis and to operates as a well with a controller and allows testing and developing of control algorithms. The next developing applies control technics to PCP system to optimize pumping velocity to achieve productivity and durability of downhole components. The mathematical model is linearized to apply conventional control technics including observability and controllability of the system and develop design rules for PI controller. Stability conditions are stated for operation point of the system. A fuzzy rule-based control system are developed from a PI controller using a inference machine based on Mandami operators. The fuzzy logic is applied to develop a specialist system that selects PCP equipments too. The developed technics to simulate and the linearized model was used in an actual well where a control system is installed. This control system consists of a pump intake pressure sensor, an industrial controller and a variable speed drive. The PI control was applied and fuzzy controller was applied to optimize simulated and actual well operation and the results was compared. The simulated and actual open loop response was compared to validate simulation. A case study was accomplished to validate equipment selection specialist system / O sistema de eleva??o por bombeio de cavidades progressivas, BCP, tem se tornado uma importante tecnologia de produ??o de po?os de petr?leo. Na medida em que cresce o uso desta t?cnica, torna-se cada vez mais ?til o conhecimento de seu comportamento din?mico, a aplica??o das tecnologias de controle e o desenvolvimento de sistemas especialistas para dimensionamento dos equipamentos. Este trabalho apresenta o desenvolvimento de ferramentas de an?lise, controle e dimensionamento a serem aplicadas a este m?todo de eleva??o. O m?todo de eleva??o artificial por bombeio de cavidades progressivas ? composto por uma bomba de cavidades progressivas instalada dentro do po?o na extremidade inferior da coluna de produ??o atrav?s das quais o fluido ? bombeado. A bomba, que consiste de duas pe?as, um estator e um rotor ? acionada atrav?s da rota?ao do rotor atrav?s de uma coluna de hastes. Os equipamentos de superf?cie geram e transmitem a rota??o para esta coluna de hastes. Em primeiro lugar, apresenta-se o desenvolvimento de uma modelagem matem?tica din?mica completa do sistema de eleva??o por bombeio de cavidades progressivas. Este modelo ? simplicado para uso em diversas situa??es, inclusive a condi??o de regime permanente para fins de dimensionamento do sistema. A partir deste modelo matem?tico foi desenvolvido um simulador din?mico do sistema capaz de auxiliar na an?lise do sistema e atuar em conjunto com controladores de forma a permitir o teste e desenvolvimento de algoritmos de controle. O desenvolvimento seguinte visa aplicar as t?cnicas de controle ao sistema de eleva??o por bombeio de cavidades progressivas com a finalidade de otimizar a velocidade de bombeio de forma a se obter produtividade e durabilidade dos componentes de sub- superf?cie. ? feita a lineariza??o do modelo matem?tico, permitindo aplicar as t?cnicas convencionais de controle, incluindo a an?lise de observabilidade e controlabilidade, estabelecendo t?cnicas de projeto de controle PI. As condi??es de estabilidade s?o estabelecidas em torno do ponto de opera??o para o modelo linearizado. ?, tamb?m, desenvolvido um sistema de controle fuzzy baseado em regras a partir de um sistema de controle PI utilizando uma m?quina de infer?ncia baseada nas t-normas de Mandami. A l?gica fuzzy tamb?m ? aplicada no desenvolvimento de um sistema especialista para dimensionamento de BCP baseado em l?gica fuzzy. As t?cnicas de simula??o, lineariza??o e obten??o da fun??o de transfer?ncia linearizada foram aplicadas a um po?o real ao qual foi implementado um sistema de controle constitu?do de sensor de press?o de suc??o da bomba, controlador industrial e variador de freq??ncia. Aplicaram-se as t?cnicas de projeto de controle PI e controlador fuzzy ao po?o e comparou-se o comportamento dos dois controladores por simula??o. A resposta em malha aberta da fun??o de transfer?ncia foi comparada com a resposta em malha aberta medida no po?o, para fins de valida??o da t?cnica de modelagem matem?tica e de simula??o utilizadas. Foi realizado um estudo de caso de dimensionamento de sistema BCP para valida??o do sistema especialista

Made available in DSpace on 2014-12-17T14:58:00Z (GMT). No. of bitstreams: 1 RairamFCA_DISSERT2.pdf: 4758176 bytes, checksum: bfb1653549a50848b4721bda9a78bd6e (MD5) Previous issue date: 2010-03-26 / The pumping through progressing cavities system has been more and more employed in the petroleum industry. This occurs because of its capacity of elevation of highly viscous oils or fluids with great concentration of sand or other solid particles. A Progressing Cavity Pump (PCP) consists, basically, of a rotor - a metallic device similar to an eccentric screw, and a stator - a steel tube internally covered by a double helix, which may be rigid or deformable/elastomeric. In general, it is submitted to a combination of well pressure with the pressure generated by the pumping process itself. In elastomeric PCPs, this combined effort compresses the stator and generates, or enlarges, the clearance existing between the rotor and the stator, thus reducing the closing effect between their cavities. Such opening of the sealing region produces what is known as fluid slip or slippage, reducing the efficiency of the PCP pumping system. Therefore, this research aims to develop a transient three-dimensional computational model that, based on single-lobe PCP kinematics, is able to simulate the fluid-structure interaction that occurs in the interior of metallic and elastomeric PCPs. The main goal is to evaluate the dynamic characteristics of PCP s efficiency based on detailed and instantaneous information of velocity, pressure and deformation fields in their interior. To reach these goals (development and use of the model), it was also necessary the development of a methodology for generation of dynamic, mobile and deformable, computational meshes representing fluid and structural regions of a PCP. This additional intermediary step has been characterized as the biggest challenge for the elaboration and running of the computational model due to the complex kinematic and critical geometry of this type of pump (different helix angles between rotor and stator as well as large length scale aspect ratios). The processes of dynamic generation of meshes and of simultaneous evaluation of the deformations suffered by the elastomer are fulfilled through subroutines written in Fortan 90 language that dynamically interact with the CFX/ANSYS fluid dynamic software. Since a structural elastic linear model is employed to evaluate elastomer deformations, it is not necessary to use any CAE package for structural analysis. However, an initial proposal for dynamic simulation using hyperelastic models through ANSYS software is also presented in this research. Validation of the results produced with the present methodology (mesh generation, flow simulation in metallic PCPs and simulation of fluid-structure interaction in elastomeric PCPs) is obtained through comparison with experimental results reported by the literature. It is expected that the development and application of such a computational model may provide better details of the dynamics of the flow within metallic and elastomeric PCPs, so that better control systems may be implemented in the artificial elevation area by PCP / O sistema de bombeamento por cavidades progressivas est? sendo cada vez mais empregado na ind?stria do petr?leo, devido ? sua capacidade de eleva??o de ?leos altamente viscosos ou de fluidos com grandes concentra??es de areia ou outras part?culas s?lidas. Uma Bomba de Cavidades Progressivas (BCP) ? composta, basicamente, por um rotor - uma pe?a met?lica de forma semelhante a um parafuso exc?ntrico, e um estator - um tubo de a?o revestido internamente por uma h?lice dupla, a qual pode ser r?gida ou deform?vel/elastom?rica. Em geral, uma BCP ? submetida a uma combina??o de press?o do po?o com press?o gerada pelo pr?prio processo de bombeio. Em BCPs elastom?ricas, essa combina??o de esfor?os comprime o estator, gerando ou aumentando a folga existente entre o rotor e o estator, reduzindo, portanto, o efeito de veda??o entre suas cavidades. Tal abertura da regi?o de selagem produz o que ? conhecido como escorregamento do fluido, diminuindo, com isso, a efici?ncia de sistema de bombeio por BCP. Dessa maneira, este trabalho se prop?e a desenvolver um modelo computacional tridimensional transiente do processo din?mico da intera??o fluido-estrutural (FSI) que ocorre no interior de BCPs met?licas e elastom?ricas. O objetivo principal ? avaliar, a partir do uso do modelo desenvolvido, as caracter?sticas din?micas de efici?ncia de bombeio por BCPs, em fun??o de informa??es locais e instant?neas detalhadas dos campos de velocidade, press?o e deforma??o no seu interior. Para o alcance de tais metas (desenvolvimento e uso do modelo), fez-se necess?rio o desenvolvimento de uma metodologia pr?pria para gera??o de malhas computacionais din?micas, m?veis e deform?veis, representando as regi?es fluida e estrutural de uma BCP. Tal procedimento caracterizou-se como o maior desafio para a elabora??o do modelo computacional, devido ? cinem?tica complexa e ? geometria cr?tica desse tipo de bomba (?ngulos de h?lice diferentes entre rotor e estator e grandes diferen?as de escala de comprimento). Os processos de gera??o din?mica das malhas e de avalia??o simult?nea das deforma??es sofridas pelo elast?mero s?o realizados atrav?s de sub-rotinas em linguagem Fortran 90, as quais interagem dinamicamente com o software de din?mica dos fluidos computacional CFX/ANSYS. Desde que o modelo linear el?stico ? empregado para avaliar as deforma??es elastom?ricas, n?o ? necess?rio usar nenhum software para an?lise estrutural. Entretanto, uma proposta inicial para simula??o din?mica no ANSYS empregando-se modelos constitutivos hiper-el?sticos para o elast?mero ? tamb?m apresentada no presente trabalho. A valida??o dos resultados produzidos com a presente metodologia (gera??o de malha, simula??o do escoamento em BCPs met?licas e simula??o da intera??o fluido-estrutural em BCPs elastom?ricas) ? obtida atrav?s da compara??o com resultados experimentais reportados pela literatura. Vislumbra-se que o desenvolvimento e aplica??o de tal ferramenta computacional poder?o fornecer maiores detalhes da din?mica do escoamento no interior de BCPs met?licas e elastom?ricas, de maneira que melhores sistemas de controle possam ser implementados na ?rea de eleva??o artificial por BCPs