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The replacement of geothermal reservoir brine as a means of reducing solids precipitation and scale formation

Description: A number of technical difficulties are encountered in producing geothermal energy from reservoirs containing brines with high concentrations of dissolved solids. The reduction in temperature and pressure associated with brine production results in the precipitation of solids which can form heavy scale in producing and injection wells and in surface equipment. Evidently under many conditions precipitates form in the reservoir surrounding producing wells, thereby reducing their productivity. In some cases the precipitation of solids is so severe that it can prevent economic production. This paper presents results of an investigation of the possibility of injecting a different water in a geothermal reservoir as a means of reducing problems caused by solids precipitation and scale formation. Corrosion problems may also be reduced depending upon the water-rock-metal behavior. The results are confined chiefly to reservoir mechanics, a logical first step in evaluating the process for a given reservoir. Water-rock chemistry, water treating, water supply, brine disposal and overall economics are discussed only briefly or are beyond the scope of this paper. In general the composition of water injected into geothermal reservoirs does not remain the same. In addition to mixing with the original water the injected water tends to equilibrate with the reservoir rock. if fresh water is injected it may pick up such minerals as silica, carbonate, iron, sulfur, etc. These minerals may precipitate and cause problems in producing the reservoir. Nevertheless, under suitable conditions, a change in the reservoir water may be an attractive alternative to cycling the original reservoir brine.
Date: January 1, 1978
Creator: Martin, John C.
Partner: UNT Libraries Government Documents Department

A vector study of linearized supersonic flow applications to nonplanar problems

Description: Report presenting a vector study of the partial-differential equation of steady linearized supersonic flow. General expressions are derived which relate the velocity potential in the stream to the conditions on the disturbing surfaces. A discussion of problems dealing with planar bodies is given and the conditions for the solution to be unique are investigated.
Date: June 1952
Creator: Martin, John C.
Partner: UNT Libraries Government Documents Department

A vector study of linearized supersonic flow applications to nonplanar problems

Description: A vector study of the partial-differential equation of steady linearized supersonic flow is presented. General expressions which relate the velocity potential in the stream to the conditions on the disturbing surfaces, are derived. In connection with these general expressions the concept of the finite part of an integral is discussed. A discussion of problems dealing with planar bodies is given and the conditions for the solution to be unique are investigated. Problems concerning nonplanar systems are investigated, and methods are derived for the solution of some simple nonplanar bodies. The surface pressure distribution and the damping in roll are found for rolling tails consisting of four, six, and eight rectangular fins for the Mach number range where the region of interference between adjacent fins does not affect the fin tips.
Date: October 25, 1951
Creator: Martin, John C.
Partner: UNT Libraries Government Documents Department

The calculation of downwash behind wings of arbitrary plan form at supersonic speeds

Description: Report presenting exact and approximate methods based on linearized supersonic flow theory for the calculation of the velocity potential and the downwash from thin wings of arbitrary plan form. The applicability of the method inherently depends on a knowledge of the load distribution over the plan form of the wing.
Date: July 1950
Creator: Martin, John C.
Partner: UNT Libraries Government Documents Department

Span load distributions resulting from angle of attack, rolling, and pitching for tapered sweptback wings with streamwise tips: Supersonic leading and trailing edges

Description: Report presenting the span load distributions resulting from constant angle of attack, steady rolling, and steady pitching for a series of thin sweptback tapered wings with streamwise tips and supersonic leading and trailing edges. The results of the analysis are presented as a series of design charts.
Date: July 1952
Creator: Martin, John C. & Jeffreys, Isabella
Partner: UNT Libraries Government Documents Department

Calculation of lift and pitching moments due to angle of attack and steady pitching velocity at supersonic speeds for thin sweptback tapered wings with streamwise tips and supersonic leading and trailing edges

Description: Report presenting a derivation for a series of thin sweptback tapered wings with streamwise tips and supersonic leading and trailing edges. The results of the analysis are presented as a series of design charts. Results regarding formulas and computations for several derivatives, chordwise center-of-pressure location, and extensions of the results by the use of reversibility theorems are provided.
Date: June 1952
Creator: Martin, John C.; Margolis, Kenneth & Jeffreys, Isabella
Partner: UNT Libraries Government Documents Department

Aerodynamics of a rectangular wing of infinite aspect ratio at high angles of attack and supersonic speeds

Description: From Introduction: "The present paper contains a first-order evaluation of a number of aerodynamic derivatives for a rectangular wing of infinite aspect ratio at finite angles of attack, based upon the linear perturbation theory for rotational flow."
Date: July 1955
Creator: Martin, John C. & Malvestuto, Frank S., Jr.
Partner: UNT Libraries Government Documents Department

Theoretical force and moments due to sideslip of a number of vertical tail configurations at supersonic speeds

Description: Report presenting formulas obtained by means of the linearized supersonic-flow theory for the lateral force due to sideslip, the yawing moment due to sideslip, and the rolling moment due to sideslip for normal tail arrangements consisting of rectangular, triangular, and sweptback vertical tails of arbitrary taper and sweep mounted symmetrically on a horizontal tail of arbitrary shape.
Date: September 1951
Creator: Martin, John C. & Malvestuto, Frank S., Jr.
Partner: UNT Libraries Government Documents Department

Theoretical calculations of the lateral force and yawing moment due to rolling at supersonic speeds for sweptback tapered wings with streamwise tipssupersonic leading edges

Description: Report presenting theoretical results for the lateral force and yawing moment due to combined angle of attack and roll. The thin wings are tapered and have leading and trailing edges which are each swept at a constant angle; the tips are parallel to the center section.
Date: July 1950
Creator: Harmon, Sidney M. & Martin, John C.
Partner: UNT Libraries Government Documents Department

A theoretical investigation of the aerodynamics of wing-tail combinations performing time-dependent motions at supersonic speeds

Description: Report presenting a theoretical investigation of the contribution of horizontal tails to the lift and pitching moment due to angle of attack, a constant rate of pitch, and a constant vertical acceleration. Methods for calculating the flow fields behind wings with constant vertical acceleration are developed.
Date: May 1954
Creator: Martin, John C.; Diederich, Margaret S. & Bobbitt, Percy J.
Partner: UNT Libraries Government Documents Department