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Some measurements of boiling burn-out

Description: Report presenting measurements of boiling burn-out heat flux for water flowing upward through an electrically heated tube for ranges of velocity, pressure, length-diameter ratios, and subcooling.
Date: February 23, 1955
Creator: Lowdermilk, Warren H. & Weiland, Walter F.
Partner: UNT Libraries Government Documents Department

Resistance of various materials to attack by molten bismuth-lead eutectic at elevated temperatures

Description: The resistance of 40 materials including alloys, ceramics, ceramals, and pure metals to attack by bismuth-lead eutectic at temperatures between 1500 and 2000 F was investigated. A velocity of 15 feet per second was maintained between the material surface and the bismuth-lead eutectic. Those materials found to be resistant to this attack included 17 of the ceramals and ceramics, graphite, and arc-cast molybdenum. All other materials investigated were appreciably attacked by the eutectic in the form of uniform attack, cavitation, or pitting, as indicated by metallographic analysis. No evidence of intergranular corrosion was observed in any of the materials studied in this investigation. Disintegration rates were estimated in mils per year from linear measurements taken before and after the specimens were subjected to attack by the molten eutectic.
Date: September 26, 1951
Creator: Gangler, James J. & Engel, Walter J.
Partner: UNT Libraries Government Documents Department

Supersonic free-flight measurement of heat transfer and transition on a 10 degree cone having a low temperature ratio

Description: Report presenting an investigation of the heat-transfer coefficients (Stanton number and boundary-layer transition) obtained from a free-flight test of a 10 degree total-angle cone with a 1/16-inch tip radius. Testing occurred over a range of Mach numbers from 1.8 to 3.5 and a range of wall-to-local-stream temperature ratios. Results regarding skin temperatures, heat-transfer coefficient, and boundary-layer transition are presented.
Date: January 31, 1957
Creator: Merlet, Charles F. & Rumsey, Charles B.
Partner: UNT Libraries Government Documents Department

Transient Temperature in Infinite Plates, Infinite Cylinders, and Spheres Following a Simultaneous Step Change in Internal Heat Generation Rate, Coolant Temperature and Heat Transfer Coefficient

Description: Report regarding the problem of transient temperature in infinite plates, infinite cylinders, and spheres following during convective cooling after heat generation.
Date: 1958
Creator: Epel, Lester G.
Partner: UNT Libraries Government Documents Department

Thermodynamic and Related Properties of Parahydrogen From the Triple Point to 100 K at Pressures to 340 Atmospheres

Description: From Introduction: "In the present report, therefore, polynomials representing isotherms and isochores are combined with numerical methods of computation for the purpose of improving accuracy, in particular for the derivatives of the P-p-T surface."
Date: August 10, 1965
Creator: Roder, H. M.; Weber, L. A. & Goodwin, R. D.
Partner: UNT Libraries Government Documents Department

Thermodynamic Data for Mineral Technology

Description: From Introduction: "This compilation is part of the Bureau of Mines continuing effort to provide information for use as guidelines in mineral technology advancement, pollution control, and energy economy."
Date: unknown
Creator: Pankratz, L. B.; Stuve, J. M. & Gokcen, N. A.
Partner: UNT Libraries Government Documents Department

Thermodynamic Properties of Saline Water

Description: From Abstract: "Activity coefficients of calcium sulfate were calculated from solubilities of gypsum in 0 to 1.0m sodium chloride at temperatures from 25 degrees C to 95 degrees C. X-ray diffraction studies for calcium sulfate modifications before and after contact with aqueous and saline solutions are given."
Date: July 1964
Creator: Power, W. H. & Fabuss, B. M.
Partner: UNT Libraries Government Documents Department

Periodic Heat Transfer at Small Pressure Fluctuations

Description: The effect of cyclic gas pressure variations on the periodic heat transfer at a flat wall is theoretically analyzed and the differential equation describing the process and its solution for relatively. Small pressure fluctuations developed, thus explaining the periodic heat cycle between gas and wall surface. The processes for pure harmonic pressure and temperature oscillations, respectively, in the gas space are described by means of a constant heat transfer coefficient and the equally constant phase angle between the appearance of the maximum values of the pressure and heat flow most conveniently expressed mathematically in the form of a complex heat transfer coefficient. Any cyclic pressure oscillations, can be reduced by Fourier analysis to harmonic oscillations, which result in specific, mutual relationships of heat-transfer coefficients and phase angles for the different harmonics.
Date: September 1, 1943
Creator: Pfriem, H.
Partner: UNT Libraries Government Documents Department

Report on Investigation of Developed Turbulence

Description: The recent experiments by Jakob and Erk, on the resistance of flowing water in smooth pipes, which are in good agreement with earlier measurements by Stenton and Pannell, have caused me to change my opinion that the empirical Blasius law (resistance proportional to the 7/4 power of the mean velocity) was applicable up to arbitrarily high Reynolds numbers. According to the new tests the exponent approaches 2 with increasing Reynolds number, where it remains an open question whether or not a specific finite limiting value of the resistance factor lambda is obtained at R = infinity. With the collapse of Blasius' law the requirements which produced the relation that the velocity in the proximity of the wall varied in proportion to the 7th root of the wall distance must also become void. However, it is found that the fundamental assumption that led to this relationship can be generalized so as to furnish a velocity distribution for any empirical resistance law. These fundamental assumptions can be so expressed that for the law of velocity distribution in proximity of the wall as well as for that of friction at the wall, a form can be found in which the pipe diameter no longer occurs, or in other words, that the processes in proximity of a wall are not dependent upon the distance of the opposite wall.
Date: January 18, 1949
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department

Theory of Heat Transfer in Smooth and Rough Pipes

Description: The heat transfer accompanying turbulent flow in tubes has been treated by a new theory of wall turbulence, and a formula for smooth tubes has been derived which is asymptotic at Re approaches infinity. It agrees very well with the data available to date. The formula also holds for the flow along a flat plate if lambda is based on the velocity far away. For rough tubes, the unit conductance is shown to be a function of kv*/upsilon; the two empirical constants (delta(r), n) which appear in equation (52) cannot yet be determined because of lack of experimental data.
Date: December 1, 1942
Creator: Mattioli, G. D.
Partner: UNT Libraries Government Documents Department

The Turbulent Flow in Diffusers of Small Divergence Angle

Description: The turbulent flow in a conical diffuser represents the type of turbulent boundary layer with positive longitudinal pressure gradient. In contrast to the boundary layer problem, however, it is not necessary that the pressure distribution along the limits of the boundary layer(along the axis of the diffuser) be given, since this distribution can be obtained from the computation. This circumstance, together with the greater simplicity of the problem as a whole, provides a useful basis for the study of the extension of the results of semiempirical theories to the case of motion with a positive pressure gradient. In the first part of the paper,formulas are derived for the computation of the velocity and.pressure distributions in the turbulent flow along, and at right angles to, the axis of a diffuser of small cone angle. The problem is solved.
Date: October 1, 1947
Creator: Gourzhienko, G. A.
Partner: UNT Libraries Government Documents Department

Subsonic Gas Flow Past A Wing Profile

Description: The use of the linearized equations of Chaplygin to calculate the subsonic flow of a gas permits solving the problem of the flow about a wing profile for absence and presence of circulation. The solution is obtained in a practical convenient form that permits finding all the required magnitudes for the gas flow (lift, lift moment velocity distribution over the profile, and critical Mach number). This solution is not expressed in simple closed form; for a certain simplifying assumption, however, the equations of Chaplygin can be reduced to equations with constant coefficients, and solutions are obtained by using only the mathematical apparatus of the theory of functions of a complex variable. The method for simplifying the equations was pointed out by Chaplygin himself. These applied similar equations to the solution of the flow problem and obtained a solution for the case of the absence of circulation.
Date: July 1, 1950
Creator: Christianovich, S. A. & Yuriev, I. M.
Partner: UNT Libraries Government Documents Department

On the Theory of the Laval Nozzle

Description: In the present paper, the motion of a gas in a plane-parallel Laval nozzle in the neighborhood of the transition from subsonic to supersonic velocities is studied. In a recently published paper, F. I. Frankl, applying the holograph method of Chaplygin, undertook a detailed investigation of the character of the flow near the line of transition from subsonic to supersonic velocities. From the results of Tricomi's investigation on the theory of differential equations of the mixed elliptic-hyperbolic type, Frankl introduced as one of the independent variables in place of the modulus of the velocity, a certain specially chosen function of this modulus. He thereby succeeded in explaining the character of the flow at the point of intersection of the transition line and the axis of symmetry (center of the nozzle) and in studying the behavior of the stream function in the neighborhood of this point by separating out the principal term having, together with its derivatives, the maximum value as compared with the corresponding corrections. This principal term is represented in Frankl's paper in the form of a linear combination of two hypergeometric functions. In order to find this linear combination, it is necessary to solve a number of boundary problems, which results in a complex analysis. In the investigation of the flow with which this paper is concerned, a second method is applied. This method is based on the transformation of the equations of motion to a form that may be called canonical for the system of differential equations of the mixed elliptic-hyperbolic type to which the system of equations of the motion of an ideal compressible fluid refers. By studying the behavior of the integrals of this system in the neighborhood of the parabolic line, the principal term of the solution is easily separated out in the form ...
Date: April 1, 1949
Creator: Falkovich, S. V.
Partner: UNT Libraries Government Documents Department

Heat of Combustion of the Product Formed by the Reaction of Acetylene, Ethylene, and Diborane

Description: The net heat of combustion of the product formed by the reaction of diborane with a mixture of acetylene and ethylene was found to be 20,440 +/- 150 Btu per pound for the reaction of liquid fuel to gaseous carbon dioxide, gaseous water, and solid boric oxide. The measurements were made in a Parr oxygen-bomb calorimeter, and the combustion was believed to be 98 percent complete. The estimated net-heat of combustion for complete combustion would therefore be 20,850 +/- 150 Btu per pound.
Date: October 24, 1957
Creator: Tannenbaum, Stanley
Partner: UNT Libraries Government Documents Department

Experimental Determination of Linear Dynamics of Two-Spool Turbojet Engines

Description: Transfer functions descriptive of the response of most engine variables were determined from transient data that were obtained from approximate step inputs in fuel flow and in exhaust-nozzle area. The speed responses of both spools to fuel flow and to turbine-inlet temperature appeared as identical first-order lags. Response to exhaust-nozzle area was characterized by a first-order lag response of the outer-spool speed, accompanied by virtually no change in inner-spool speed.
Date: October 18, 1954
Creator: Novik, David & Heppler, Herbert
Partner: UNT Libraries Government Documents Department

Effect of Some External Crosswise Stiffeners on the Heat Transfer and Pressure Distribution on a Flat Plate at Mach Numbers of 0.77, 1.39, and 1.98. Coord. No. AF-AM-69

Description: The heat transfer and pressures on the surfaces of several flat-plate models with various external crosswise stiffener arrangements are presented. The tests were made in a free jet at Mach numbers of 0.77, 1.39, and 1.98 for Reynolds numbers of 3 x 10(exp 6), 7 x 10(exp 6), and 14 x 10(exp 6), respectively, based on a length of 1 foot. The addition of external crosswise stiffeners to the flat-plate models caused large pressure and heat-transfer variations on the surfaces of the models.
Date: May 14, 1957
Creator: Carter, Howard S.
Partner: UNT Libraries Government Documents Department

Contributions to the Data on Theoretical Metallurgy: [Part] 15. A Reprint of Bulletins 383, 384, 393, and 406

Description: Report issued by the Bureau of Mines containing a compilation of four previously printed Bulletins discussing thermodynamics and inorganic substances. The four reprints included are bulletins 383, 384, 393, and 406, and are each printed in full. This report includes tables.
Date: 1962
Creator: Kelley, K. K.
Partner: UNT Libraries Government Documents Department

Pressure Distribution in Nonuniform Two-Dimensional Flow

Description: In an attempt to follow the time rate of change of the processes in turbulent flows by quantitative measurements the measurement of the pressure is often beset with insuperable difficulties for the reason that the speeds and hence the pressures to be measured are often very small. On the other hand, the measurement of very small pressures requires, at least, considerable time, so that the follow-up of periodically varying processes is as goad as impossible. In order to obviate these difficulties a method, suggested by Prof. Prandtl, has been developed by which the pressure distribution is simply determined from the photographic flow picture. This method is described and proved on a worked-out example. It was found that quantitatively very satisfactory results can be achieved.
Date: January 1, 1943
Creator: Schwabe, M.
Partner: UNT Libraries Government Documents Department

Pressure Distribution Measurements on a Turbine Rotor Blade Passing Behind a Turbine Nozzle Lattice

Description: As a turbine rotor turns, the blades traverse the wake zones of the nozzle vanes. A periodic fluctuation of the pressure distribution around the circumference of the rotor blade is therefore caused. It was desired to investigate quantitatively this effect. At the same time, the magnitude of the force acting upon one profile of the rotor-blade lattice at various positions of this lattice relative to the nozzle lattice was to be determined.
Date: September 1, 1947
Creator: Hausenblas
Partner: UNT Libraries Government Documents Department

Statistical Study of Turbulence: Spectral Functions and Correlation Coefficients

Description: In reading the publications on turbulence of different authors, one often runs the risk of confusing the various correlation coefficients and turbulence spectra. We have made a point of defining, by appropriate concepts, the differences which exist between these functions. Besides, we introduce in the symbols a few new characteristics of turbulence. In the first chapter, we study some relations between the correlation coefficients and the different turbulence spectra. Certain relations are given by means of demonstrations which could be called intuitive rather than mathematical. In this way we demonstrate that the correlation coefficients between the simultaneous turbulent velocities at two points are identical, whether studied in Lagrange's or in Euler's systems. We then consider new spectra of turbulence, obtained by study of the simultaneous velocities along a straight line of given direction. We determine some relations between these spectra and the correlation coefficients. Examining the relation between the spectrum of the turbulence measured at a fixed point and the longitudinal-correlation curve given by G. I. Taylor, we find that this equation is exact only when the coefficient is very small.
Date: July 1, 1958
Creator: Frenkiel, Francois N.
Partner: UNT Libraries Government Documents Department