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Geothermal water and gas: collected methods for sampling and analysis. Comment issue. [Compilation of methods]

Description: A collection of methods for sampling and analysis of geothermal fluids and gases is presented. Compilations of analytic options for constituents in water and gases are given. Also, a survey of published methods of laboratory water analysis is included. It is stated that no recommendation of the applicability of the methods to geothermal brines should be assumed since the intent of the table is to encourage and solicit comments and discussion leading to recommended analytical procedures for geothermal waters and research. (WHK)
Date: August 1, 1976
Creator: Douglas, J. G.; Serne, R. J.; Shannon, D. W. & Woodruff, E. M.
Partner: UNT Libraries Government Documents Department
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Time Scaling of the Rates of Produced Fluids in Laboratory Displacements

Description: In this report, the use of an asymptotic method, based on the time scaling of the ratio of produced fluids, to infer the relative permeability exponent of the displaced phase near its residual saturation, for immiscible displacements in laboratory cores was proposed. Sufficiently large injection rates, the existence of a power law can be detected, and its exponent inferred, by plotting in an appropriate plot the ratio of the flow rates of the two fluids at the effluent for some time after breakthrough.
Date: February 27, 2001
Creator: Laroche, Catherine; Chen, Min; Yortsos, Yanis C. & Kamath, Jairam
Partner: UNT Libraries Government Documents Department
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Air-Water Analogy and the Study of Hydraulic Models

Description: From Summary: "The author first sets forth some observations about the theory of models. Then he established certain general criteria for the construction of dynamically similar models in water and in air, through reference to the perfect fluid equations and to the ones pertaining to viscous flow. It is, in addition, pointed out that there are more cases in which the analogy is possible than is commonly supposed."
Date: July 1953
Creator: Supino, Giulio
Partner: UNT Libraries Government Documents Department
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Compatibility of manufacturing process fluids with R-134a and polyolester lubricant. Final report

Description: This report includes a broad list of processing fluids that are known to be used to manufacture air conditioning and refrigeration products. Sixty-four process fluids from this list were selected for compatibility studies with R-134a and ICI EMKARATE RL32H (32 ISO) polyolester lubricant. Solutions or suspensions of the process fluid residues in polyolester lubricant were heated for 14 days at 175{degrees}C (347{degrees}F) in evacuated sealed glass tubes containing only valve steel coupons. Miscibility tests were performed at 90 wt.% R-134a, 10 wt.% polyolester lubricant with process fluid residue contaminate and were scanned in 10{degrees}C (18{degrees}F) increments over a temperature range of ambient to -40{degrees}C (-40{degrees}F). Any sign of turbidity, haze formation or oil separation was considered the immiscibility point.
Date: July 1, 1996
Creator: Cavestri, R.C. & Schooley, D.L.
Partner: UNT Libraries Government Documents Department
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On subsonic compressible flows by a method of correspondence II : application of methods to studies of flow with circulation about a circular cylinder

Description: A general method for studying the flow of a compressible fluid around a closed body was discussed in Part I of this report. Here, application is made to the specific case in which the linearized equation of state is used. For a given incompressible flow around a specific profile, a corresponding compressible flow is found. The flow at infinity remains unchanged. Detailed studies are made of the flow with circulation around a unit circle, and velocity distributions are found for a wide range of Mach number and angle of attack. Comparisons are made with other methods.
Date: April 1947
Creator: Gelbart, Abe & Bartnoff, Shepard
Partner: UNT Libraries Government Documents Department
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On a function-theory method for obtaining potential-flow patterns of a compressible fluid

Description: Report presenting a method for obtaining exact potential-flow patterns in a compressible fluid. The method is based on a complex-function theory developed for the solutions of the simultaneous first-order partial differential equations in the hodograph variables.
Date: July 1943
Creator: Gelbart, Abe
Partner: UNT Libraries Government Documents Department
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Unsteady flows of in homogeneous in compressible fluids

Description: In this paper, we study the unsteady motion of in homogeneous in compressible viscous fluids. We present the results corresponding to Stokes second problem and for the flow between two parallel plates where one is oscillating.
Date: January 1, 2011
Creator: Massoudi, Mehrdad & Vaidya, Ashwin
Partner: UNT Libraries Government Documents Department
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Well blowout rates in California Oil and Gas District 4--Update and Trends

Description: Well blowouts are one type of event in hydrocarbon exploration and production that generates health, safety, environmental and financial risk. Well blowouts are variously defined as 'uncontrolled flow of well fluids and/or formation fluids from the wellbore' or 'uncontrolled flow of reservoir fluids into the wellbore'. Theoretically this is irrespective of flux rate and so would include low fluxes, often termed 'leakage'. In practice, such low-flux events are not considered well blowouts. Rather, the term well blowout applies to higher fluxes that rise to attention more acutely, typically in the order of seconds to days after the event commences. It is not unusual for insurance claims for well blowouts to exceed US$10 million. This does not imply that all blowouts are this costly, as it is likely claims are filed only for the most catastrophic events. Still, insuring against the risk of loss of well control is the costliest in the industry. The risk of well blowouts was recently quantified from an assembled database of 102 events occurring in California Oil and Gas District 4 during the period 1991 to 2005, inclusive. This article reviews those findings, updates them to a certain extent and compares them with other well blowout risk study results. It also provides an improved perspective on some of the findings. In short, this update finds that blowout rates have remained constant from 2005 to 2008 within the limits of resolution and that the decline in blowout rates from 1991 to 2005 was likely due to improved industry practice.
Date: October 1, 2009
Creator: Jordan, Preston D. & Benson, Sally M.
Partner: UNT Libraries Government Documents Department
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Performance characteristics of the Lysholm engine

Description: The performance of a 5 in. diameter rotor Lysholm engine prototype running on simulated geothermal flows from 16 to 100% quality is described. Staging was performed with conventional Westinghouse 25 kW steam turbines demonstrating that such a process is feasible. Maximum efficiency and power noted were 37.2% and 26.3 kW respectively, but inhibiting factors were discovered which, upon correction, should allow efficiencies around 50% and powers up to 35 kW. Larger engines with minor modifications should get better efficiencies. Data was taken for inlet pressures of 75 to 120 psia and speeds of 3000 to 9000 rpm's. Further testing under similar conditions is planned.
Date: January 1, 1980
Creator: Berger, Ralph Edward
Partner: UNT Libraries Government Documents Department
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Tracing Geothermal Fluids

Description: Geothermal water must be injected back into the reservoir after it has been used for power production. Injection is critical in maximizing the power production and lifetime of the reservoir. To use injectate effectively the direction and velocity of the injected water must be known or inferred. This information can be obtained by using chemical tracers to track the subsurface flow paths of the injected fluid. Tracers are chemical compounds that are added to the water as it is injected back into the reservoir. The hot production water is monitored for the presence of this tracer using the most sensitive analytic methods that are economically feasible. The amount and concentration pattern of the tracer revealed by this monitoring can be used to evaluate how effective the injection strategy is. However, the tracers must have properties that suite the environment that they will be used in. This requires careful consideration and testing of the tracer properties. In previous and parallel investigations we have developed tracers that are suitable from tracing liquid water. In this investigation, we developed tracers that can be used for steam and mixed water/steam environments. This work will improve the efficiency of injection management in geothermal fields, lowering the cost of energy production and increasing the power output of these systems.
Date: March 1, 2004
Creator: Adams, Michael C. & Nash, Greg
Partner: UNT Libraries Government Documents Department
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Investigation of wellbore cooling by circulation and fluid penetration into the formation using a wellbore thermal simulator computer code

Description: The high temperatures of geothermal wells present severe problems for drilling, logging, and developing these reservoirs. Cooling the wellbore is perhaps the most common method to solve these problems. However, it is usually not clear what may be the most effective wellbore cooling mechanism for a given well. In this paper, wellbore cooling by the use of circulation or by fluid injection into the surrounding rock is investigated using a wellbore thermal simulator computer code. Short circulation times offer no prolonged cooling of fluid in the wellbore, but long circulation times (greater than ten or twenty days) greatly reduce the warming rate after shut-in. The dependence of the warming rate on the penetration distance of cooler temperatures into the rock formation (as by fluid injection) is investigated. Penetration distances of greater than 0.6 m appear to offer a substantial reduction in the warming rate. Several plots are shown which demonstrate these effects. 16 refs., 6 figs.
Date: January 1, 1985
Creator: Duda, L.E.
Partner: UNT Libraries Government Documents Department
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Probabilistic Risk Based Decision Support for Oil and Gas Exploration and Production Facilities in Sensitive Ecosystems

Description: This report describes work performed during the initial period of the project 'Probabilistic Risk Based Decision Support for Oil and Gas Exploration and Production Facilities in Sensitive Ecosystems.' The specific region that is within the scope of this study is the Fayetteville Shale Play. This is an unconventional, tight formation, natural gas play that currently has approximately 1.5 million acres under lease, primarily to Southwestern Energy Incorporated and Chesapeake Energy Incorporated. The currently active play encompasses a region from approximately Fort Smith, AR east to Little Rock, AR approximately 50 miles wide (from North to South). The initial estimates for this field put it almost on par with the Barnett Shale play in Texas. It is anticipated that thousands of wells will be drilled during the next several years; this will entail installation of massive support infrastructure of roads and pipelines, as well as drilling fluid disposal pits and infrastructure to handle millions of gallons of fracturing fluids. This project focuses on gas production in Arkansas as the test bed for application of proactive risk management decision support system for natural gas exploration and production. The activities covered in this report include meetings with representative stakeholders, development of initial content and design for an educational web site, and development and preliminary testing of an interactive mapping utility designed to provide users with information that will allow avoidance of sensitive areas during the development of the Fayetteville Shale Play. These tools have been presented to both regulatory and industrial stakeholder groups, and their feedback has been incorporated into the project.
Date: May 31, 2009
Creator: Thoma, Greg; Veil, John; Limp, Fred; Cothren, Jackson; Gorham, Bruce; Williamson, Malcolm et al.
Partner: UNT Libraries Government Documents Department
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The Flow of a Compressible Fluid Past a Circular Arc Profile

Description: Report presenting the use of the Ackeret iteration process to obtain higher approximations than that of Prandtl and Glauert for the flow of a compressible fluid past a circular arc profile. The procedure is to expand the velocity potential in a power series of the camber coefficient.
Date: October 1944
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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The Flow of a Compressible Fluid Past a Curved Surface

Description: Report presenting an iteration method employed to obtain the flow of a compressible fluid past a curved surface. For small Mach numbers and thin shapes, the results obtained by the iteration process agree with those obtained by the Poggi method.
Date: November 1943
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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Methods for Determination and Computation of Flow Patterns of a Compressible Fluid

Description: Note presenting a well-known method of generating stream functions of an incompressible fluid flow, which involves taking the imaginary part of an analytic function of a complex variable. This paper is specifically devoted to a detailed discussion of performing computations related to obtaining flow patterns of compressible fluid from analytic functions of a compressible fluid. An example is also provided to illustrate the method.
Date: September 1946
Creator: Bergman, Stefan
Partner: UNT Libraries Government Documents Department
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A CURRENT REVIEW OF BODY FLUID ANALYSIS, PROCEDURES, AND METHOD OF REPORTING--JANUARY 1957

Description: Direct alpha counting to determine fissile material in dilnte solutions of high total solids content is likely to be inaccurate due to the difficulty of preparing thin sources. This report describes a neutron-activation analysis method which eliminates this risk. Results obtained by the neutronactivation analysis for U/sup 238/ in solution are compared with results obtained from other methods. The standard deviation and sensitivity are shown. (auth)
Date: August 1, 1957
Creator: Brown, P.E.; Davis, D.M. & Henley, L.C.
Partner: UNT Libraries Government Documents Department
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On the Continuation of a Potential Gas Flow Across the Sonic Line

Description: "Simple, sufficient conditions are given under which a two-dimensional steady compressible flow can be continued across the line of Mach number 1 as a continuous supersonic flow. Methods for the actual computation of the flow are described. The problem is of importance in the theory of transonic flows past airfoils" (p. 1).
Date: April 1950
Creator: Bers, Lipman
Partner: UNT Libraries Government Documents Department
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The "Limiting Line" in Mixed Subsonic and Supersonic Flow of Compressible Fluids

Description: "It is well known that the vorticity for any fluid element is constant if the fluid is non-viscous and the change of state of the fluid is isentropic. When a solid body is placed in a uniform stream, the flow far ahead of the body is irrotational. Then if the flow is further assumed to be isentropic, the vorticity will be zero over the whole filed of flow. In other words, the flow is irrotational. For such flow over a solid body, it is shown by Theodorsen that the solid body experiences no resistance" (p. 1).
Date: November 1944
Creator: Tsien, Hsue-Shen
Partner: UNT Libraries Government Documents Department
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On Two-Dimensional Flows of Compressible Fluids

Description: "This report is devoted to the study of two-dimensional steady motion of a compressible fluid. It is shown that the complete flow pattern around a closed obstacle cannot be obtained by the method of Chaplygin. In order to overcome this difficulty, a formula for the stream-function of a two-dimensional subsonic flow is derived" (p. 1).
Date: August 1945
Creator: Bergman, Stefan
Partner: UNT Libraries Government Documents Department
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Graphical and Analytical Methods for the Determination of a Flow of a Compressible Fluid Around an Obstacle

Description: "Chaplygin introduced the hodograph method in the theory of compressible fluid flows and developed a method for constructing stream functions of such flows. This method, which has been extensively used in investigation of compressible fluid flows, is limited in certain respects. The expression for the stream function obtained in this manner can represent only certain types of flow patterns. In general, flow patterns obtained in this way cannot represent the whole flow around an obstacle, but only a part of such a flow, and therefore several expressions are needed in order to obtain the whole flow" (p. 1).
Date: July 1945
Creator: Bergman, Stefan
Partner: UNT Libraries Government Documents Department
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A General Through-Flow Theory of Fluid Flow With Subsonic or Supersonic Velocity in Turbomachines of Arbitrary Hub and Casing Shapes

Description: Note presenting a general steady through-flow theory of nonviscous fluid in turbomachines of arbitrary hub- and casing-wall shapes with subsonic or supersonic velocity. The theory is applicable to both direct and inverse problems and is derived primarily for use in turbomachines with thin blades of high solidity with a simple approximate correction factor for blade-thickness effect.
Date: March 1951
Creator: Wu, Chung-Hua
Partner: UNT Libraries Government Documents Department
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