Experimental Validation of Multiphase Flow Models and Testing of Multiphase Flow Meters: A Critical Review of Flow Loops Worldwide

Around the world, research into multiphase flow is performed by scientists with hugely diverse backgrounds: physicists, mathematicians and engineers from mechanical, nuclear, chemical, civil, petroleum, environmental and aerospace disciplines. Multiphase flow models are required to investigate the co-current or counter-current flow of different fluid phases under a wide range of pressure and temperature conditions and in several different configurations. To compliment this theoretical effort, measurements at controlled experimental conditions are required to verify multiphase flow models and assess their range of applicability, which has given rise to a large number of multiphase flow loops around the world. These flow loops are also used intensively to test and validate multiphase flow meters, which are devices for the in-line measurement of multiphase flow streams without separation of the phases. However, there are numerous multiphase flow varieties due to differences in pressure and temperature, fluids, flow regimes, pipe geometry, inclination and diameter, so a flow loop cannot represent all possible situations. Even when experiments in a given flow loop are believed to be sufficiently exhaustive for a specific study area, the real conditions encountered in the field tend to be very different from those recreated in the research facility. This paper presents a critical review of multiphase flow loops around the world, highlighting the pros and cons of each facility with regard to reproducing and monitoring different multiphase flow situations. The authors suggest a way forward for new developments in this area

Experimental validation of multiphase flow models and testing of multiphase flow meters: A critical review of flow loops worldwide

Around the world, research into multiphase flow is performed by scientists with hugely diverse backgrounds: physicists, mathematicians and engineers from mechanical, nuclear, chemical, civil, petroleum, environmental and aerospace disciplines. Multiphase flow models are required to investigate the co-current or counter-current flow of different fluid phases under a wide range of pressure and temperature conditions and in several different configurations. To compliment this theoretical effort, measurements at controlled experimental conditions are required to verify multiphase flow models and assess their range of applicability, which has given rise to a large number of multiphase flow loops around the world. These flow loops are also used intensively to test and validate multiphase flow meters, which are devices for the in-line measurement of multiphase flow streams without separation of the phases. However, there are numerous multiphase flow varieties due to differences in pressure and temperature, fluids, flow regimes, pipe geometry, inclination and diameter, so a flow loop cannot represent all possible situations. Even when experiments in a given flow loop are believed to be sufficiently exhaustive for a specific study area, the real conditions encountered in the field tend to be very different from those recreated in the research facility. This paper presents a critical review of multiphase flow loops around the world, highlighting the pros and cons of each facility with regard to reproducing and monitoring different multiphase flow situations. The authors suggest a way forward for new developments in this area

Liquid loading in gas wells: experimental investigation of back pressure effects on the near-wellbore reservoir

A large-scale core-flooding experimental setup was designed and constructed to investigate the back pressure effects on transient flow through porous medium, and so mimic the physical process of liquid loading and reservoir response. Between initial and final steady-state flowing conditions, where inlet pressure was maintained at a constant level while initiating a transient pressure build up at the core sample end, an “U-shaped” temporal distribution of pore fluid pressure within the medium itself was observed, which is in direct contrast to the conventional reservoir pressure profile

Labyrinth packer lowers costs for steam-injection wells

The full-length paper describes a low-cost completion technique that uses conventional tubing and replaces the expensive thermal packer with a new low-cost design. The new design allows free tubing expansion and protects casing through continuous gas circulation in the annulus. It also makes possible simultaneous injection of combustion gases from steam generators when conventional systems are used, or small amounts of nitrogen (N2) when the generators are not available

Oil and Gas Expertise for Geothermal Exploitation - the Need for Technology Transfer

Renewable energy is seen as the future source to meet the world's growing demand, with geothermal resources offering a constant and independent supply. Over the past century, the oil and gas sector has developed high level technologies for the exploitation of hydrocarbon reservoirs and this expertise should be directly transferrable to geothermal exploitation. In contrast to hydrocarbon developments, geothermal projects typically only become economic after decades of operation, which implies a long period of debt service before costs can be recovered from the sale of energy in the form of heat, electricity or a combination of both. Thus, the technology transfer between the petroleum and geothermal sectors has not been as efficient as initially hoped for. This paper begins with a review of the principles and uses of geothermal energy in today's sustainable energy scenario, from District Heating systems to the more recent Hot Dry Rock (HDR) concept. As exploiting HDR resources becomes more economic, the geothermal energy resources of countries li the U.S. could meet domestic demand for electricity for thousands of years. The challenges presented by HDR projects around the world are discussed, with a special focus on those aspects of geothermal exploitation that overlap with the oil arid gas expertise, such as drilling and completions practices, the characterization of fluid flow through porous media and in wellbores and reservoir fracturing issues. The comparison shows how hydrocarbon exploration and production complements that of geothermal exploitation and identifies technical areas where future research efforts should be addressed to enhance the technology transfer between these energy sectors

Labyrinth Packer Lowers the Costs for Steam Injection Wells: Theoretical and Experimental Results

This paper describes a low-cost completion technique that uses conventional tubing and replaces the expensive thermal packer with a new low-cost design. The new design allows free tubing expansion and protects casing through continuous gas circulation in the annulus. It also makes possible simultaneous injection of combustion gases from steam generators, when conventional systems are used, or small amounts of nitrogen, when the generators are not available

Comparison of Well Completions used in Oil/Gas Wells and Geothermal Wells: a New Approach to Technology Transfer

Renewable energy is seen as the future source for meeting the world’s growing demand, with geothermal offering a constant and independent supply. Tapping geothermal energy is not always straightforward as deep drilling is required in order to access this high -temperature resource. Geothermal drilling is expensive and is financed by the operator (usually districts or state representatives) with a long period of debt service before costs can be recovered from the energy sale (heat, electricity or a combination of both). It is reported that the success rate for geothermal wildcat wells is only 25-40%, so a reduction in the exploratory drilling costs would be a major incentive for increased exploitation of this resource. However, drilling costs are only a part of the total well expenditure. Tubulars can double the total well cost , especially when complex well completions are required. Together, drilling and well completions can account for more than half of the capital cost for a geothermal power project. This paper presents a comparison of different well completions used for oil, gas and geothermal wells. The study identifies ways in which to facilitate a faster technology transfer from the traditional oil and gas arena to the developing geothermal industry. The study provides engineers with a better understanding of geothermal well completion needs and suggests ways to reduce cost

Recovering Waste Heat from Hydrocarbon Developments to Improve Energy Efficiency Towards a More Sustainable Environment

No abstract available

Real-time Long Distance Teaching: An Overview of Two Years of Tele-teaching between Texas and Germany

This paper presents the experience gained while using a very simple and efficient tele-teaching technique based on available systems integrated in Windows packages. In contrast to expensive, time-intensive systems that use high-end technologies, our system incorporates ordinary webcams on laptop computers, Microsoft NetMeeting online conferencing software, and remote control of a distant computer. We show the advantages of these simple resources and the student response to the teaching process for a highly sophisticated petroleum engineering class delivered to students in Clausthal-Zellerfeld, Germany from offices in College Station, Texas. The experience over two years of tele-teaching using easily available standard internet messengers and MS Windows-integrated meeting packages has resulted in enthusiastic student acceptance and preference for our low-cost system over more expensive, complex approaches to distance learning. We include our recommendations for building a system that works efficiently yet minimizes the costs

The First Master in Geothermal Engineering Offered by a Petroleum Engineering School: Curriculum Challenges and Opportunities

Renewables are seen as the future source of energy to meet the world's growing demand, with geothermal resources offering a constant and independent supply. Trained staff will be needed to ensure successful implementation of ever more geothermal energy projects to help lower the dependency on energy imports and to develop a broader base in the future energy mix. The exploitation of geothermal resources faces many of the technical and commercial challenges that are encountered in oil and gas exploration and production, as well as analogous issues of social acceptance and environmental impact. Hence, it is logical to create more synergy between these two energy sectors and enhance the technology transfer, beginning with university education. A 2-year Master of Science (MS) in Geothermal Engineering, fully taught in English, has been developed at the Institute of Petroleum Engineering of Clausthal University of Technology (CUT), Germany. It is the first dedicated MS of its kind offered by a Petroleum Engineering school. Following its accreditation, classes began in earnest in October 2014. A number of courses are offered in common with the MS in Petroleum Engineering at CUT to encourage graduates to acquire the broadest skill set they can, and so improve their global marketability and career prospects. Sharing classes also offers a unique, more balanced view of the global energy panorama. This paper describes the process of assessing the need for this new MS program and the potential market acceptance of a "geothermal engineer" professional profile. It then discusses the implementation of the lessons learnt from Petroleum Engineering curricula to build a geothermal program focused on the full project cycle, from exploration to production, with the associated challenges and opportunities ahead. It is hoped that other Petroleum Engineering departments in the world will follow CUT's lead by expanding their curriculum offerings to include Geothermal Engineering