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  Partner: UNT Libraries Government Documents Department
 Collection: Technical Report Archive and Image Library
Research on Thermoelectric Heat Pumps
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Research on Vapor Reheat And Liquid-Liquid Heat Exchange
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Research Summary 1984-1985
Report on research in carcinogenesis, human radiobiology, low-level radiation, molecular biology, and toxicology.
Researches on ailerons and especially on the test loads to which they should be subjected
Aileron calculations have hitherto given greatly differing results according to different authors. It seems to be the general opinion that it is only necessary to give the ailerons such dimensions that the airplane can maneuver well, that the stresses they must undergo are relatively small, and that they are strong enough if their framework is of the order of strength as the wings to which they are attached. This article will show that the problem is really quite complex and that it should receive more attention.
Researches on direct injection in internal-combustion engines
These researches present a solution for reducing the fatigue of the Diesel engine by permitting the preservation of its components and, at the same time, raising its specific horsepower to a par with that of carburetor engines, while maintaining for the Diesel engine its perogative of burning heavy fuel under optimum economical conditions. The feeding of Diesel engines by injection pumps actuated by engine compression achieves the required high speeds of injection readily and permits rigorous control of the combustible charge introduced into each cylinder and of the peak pressure in the resultant cycle.
Researches on Preliminary Chemical Reactions in Spark-Ignition Engines
Chemical reactions can demonstrably occur in a fuel-air mixture compressed in the working cylinder of an Otto-cycle (spark ignition) internal-combustion engine even before the charge is ignited by the flame proceeding from the sparking plug. These are the so-called "prelinminary reactions" ("pre-flame" combustion or oxidation), and an exact knowledge of their characteristic development is of great importance for a correct appreciation of the phenomena of engine-knock (detonation), and consequently for its avoidance. Such reactions can be studied either in a working engine cylinder or in a combustion bomb. The first method necessitates a complicated experimental technique, while the second has the disadvantage of enabling only a single reaction to be studied at one time. Consequently, a new series of experiments was inaugurated, conducted in a motored (externally-driven) experimental engine of mixture-compression type, without ignition, the resulting preliminary reactions being detectable and measurable thermometrically.
Researches on the Piston Ring
In internal combustion engines, steam engines, air compressors, and so forth, the piston ring plays an important role. Especially, the recent development of Diesel engines which require a high compression pressure for their working, makes, nowadays, the packing action of the piston ring far more important than ever. Though a number of papers have been published in regard to researches on the problem of the piston ring, none has yet dealt with an exact measurement of pressure exerted on the cylinder wall at any given point of the ring. The only paper that can be traced on this subject so far is Mr. Nakagawa's report on the determination of the relative distribution of pressure on the cylinder wall, but the measuring method adopted therein appears to need further consideration. No exact idea has yet been obtained as to how the obturation of gas between the piston and cylinder, the frictional resistance of the piston, and the wear of the cylinder wall are affected by the intensity and the distribution of the radial pressure of the piston ring. Consequently, the author has endeavored, by employing an apparatus of his own invention, to get an exact determination of the pressure distribution of the piston ring. By means of a newly devised ring tester, to which piezoelectricity of quartz was applied, the distribution of the radial pressure of many sample rings on the market was accurately determined. Since many famous piston rings show very irregular pressure distribution, the author investigated and achieved a manufacturing process of the piston ring which will exert uniform pressure on the cylinder wall. Temperature effects on the configuration and on the mean spring power have also been studied. Further, the tests were performed to ascertain how the gas tightness of the piston ring may be affected by the number or spring power. The researches as to the frictional resistance between the piston ring and the cylinder wall were carried out, too. The procedure of study, and experiments conducted by the author, on this subject will be fully described in the following paragraphs.
Reserves, Bed Characteristics, and Coking Properties of the Willow Creek Coal Bed, Kemmerer District, Lincoln County, Wyoming
Report issued by the Bureau of Mines discussing the coal reserves and coking properties of the Willow Creek bed in Lincoln County, Wyoming. Analyses of the coal bed are presented in detail. This report includes tables, illustrations, photographs, and a map.
Reserves, Petrographic and Chemical Characteristics, and Carbonizing, Properties of Coal Occurring South of Dry Fork of Minnesota Creek, Gunnison County, Near Paonia, Colorado, and the Geology of the Area
Report issued by the Bureau of Mines discussing the geology, chemical, and carbonizing properties of Gunnison County coal reserves in Colorado. Results and analyses of the investigations conducted on the coal reserves are presented in detail. This report includes tables, maps, illustrations, and photographs.
Reservoir Characteristics of the Eunice Oil Field, Lea County, New Mexico
Report issued by the U.S. Bureau of Mines on the oil and gas production of the Eunice oil field in southeastern New Mexico. Properties of the oil field, and analysis of the oil and gas produced are presented. This report includes tables, maps, illustrations, and photographs.
Reservoir-Oil Characteristics, Aneth Field, San Juan County, Utah
Report issued by the Bureau of Mines over studies conducted on the characteristics of reservoir-oil sampled from San Juan County, Utah. The properties of each sample collected are presented. This report includes tables, graphs, maps, and illustrations.
A Residential Energy Consumption Analysis Utilizing the DOE-1 Computer Program
The DOE-1 computer program under development by Argonne National Laboratory, Lawrence Berkeley Laboratory, and Los Alamos Scientific Laboratory is used to examine energy consumption in a typical middle-class household in Cincinnati, Ohio. The program is used to compare energy consumption under different structural and environmental conditions including various levels of insulation in the walls and ceiling, double and single glazing of windows, and thermostat setback schedules.
Residual stress analysis of overspeeded disk with central hole by x-ray diffraction
An X-ray - diffraction analysis of residual surface stresses after plastic strain was introduced in a parallel-sided 3S-O aluminum disk with a central hole by two types of centrifugal overspeed is reported. Both tangential and radial stresses were generally tensile with large local variations near the hole where surface stresses may have been partly superficial. These stresses were both tensile and compressive dependent on the distance from the disk center when mass compression was effected near the hole.
Resistance and cooling power of various radiators
This reports combines the wind tunnel results of radiator tests made at the Navy Aerodynamical Laboratory in Washington during the summers of 1921, 1925, and 1926. In all, 13 radiators of various types and capacities were given complete tests for figure of merit. Twelve of these were tested for resistance to water flow and a fourteenth radiator was tested for air resistance alone, its heat dissipating capacity being known. All the tests were conducted in the 8 by 8 foot tunnel, or in its 4 by 8 foot restriction, by the writer and under conditions as nearly the same as possible. That is to say, as far as possible, the general arrangement and condition of the apparatus, the observation intervals, the ratio of water flow per unit of cooling surface, the differential temperatures, and the air speeds were the same for all.
Resistance and Spray Characteristics of a 1/13-Scale Model of the Consolidated Vultee Skate 7 Seaplane, TED No. NACA DE 338
A model of a Consolidated Vultee Aircraft Corporation Skate 7 sea-plane:was tested in Langley tank no= 2. Resistance data, 'spray photographs, and underwater photographs,are given in this report without discussion.
The resistance coefficient of commercial round wire grids
The resistance coefficients of commercial types of round wire grids were examined for the purpose of obtaining the necessary data on supercharger test stands for throttling the inducted air to a pressure corresponding to a desired air density. The measurements of the coefficients ranged up to Reynolds numbers of 1000. In the arrangement of two grids in tandem, which was necessary in order to obtain high resistance coefficients with the solidity, that is, mesh density of grid, was found to be accompanied by a further relationship with the mutual spacing of the individual grids.
Resistance of a delta wing in a supersonic flow
The resistance of a delta wing at small angle of attack in supersonic conical flow with its leading edges within the Mach cone is calculated by a method that separates out the suction force.
Resistance of a fifteen-centimeter disk
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Resistance of a plate in parallel flow at low Reynolds numbers
The present paper gives the results of measurements of the resistance of a plate placed parallel to the flow in the range of Reynolds numbers from 10 to 2300; in this range the resistance deviates from the formula of Blasius. The lower limit of validity of the Blasius formula is determined and also the increase in resistance at the edges parallel to the flow in the case of a plate of finite width.
Resistance of cascade of airfoils in gas stream at subsonic velocity
A method of computing the resistance of a cascade of airfoils in a viscous compressible gas flow is described.
Resistance of Materials to Attack by Liquid Metals
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Resistance of Metal-Mine Airways
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Resistance of plates and pipes at high Reynolds numbers
It was learned that the law of resistance for high R values does not follow the simple powers, and that the powers, which can be obtained approximately for the velocity distribution, gradually change. Since, moreover, very important investigations have recently been made on the resistance of plates at very high R values, it seemed of interest to apply the above line of reasoning to the new general law of resistance. For this purpose, the resistance and velocity distribution along the plate must always be equal to the values of the pipe flow at the corresponding Reynolds number. We made two kinds of calculations, of which the one given here is the simpler and more practical and also agrees better with the experimental results.
Resistance of six cast high-temperature alloys to cracking caused by thermal shock
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The resistance of spheres in wind tunnels and in air
To supplement the standardization tests now in progress at several laboratories, a broad investigation of the resistance of spheres in wind tunnels and free air has been carried out by the National Advisory Committee for Aeronautics. The subject has been classed in aerodynamic research, and in consequence there is available a great mass of data from previous investigations. This material was given careful consideration in laying out the research, and explanation of practically all the disagreement between former experiments has resulted. A satisfactory confirmation of Reynolds law has been accomplished, the effect of means of support determined, the range of experiment greatly extended by work in the new variable density wind tunnel, and the effects of turbulence investigated by work in the tunnels and by towing and dropping tests in free air. It is concluded that the erratic nature of most of the previous work is due to support interference and differing turbulence conditions. While the question of support has been investigated thoroughly, a systematic and comprehensive study of the effects of scale and quality of turbulence will be necessary to complete the problem, as this phase was given only general treatment.
Resistance of streamline wires
This note contains the results of tests to determine the resistance of four sizes of streamline wire. The investigation was conducted in the six-inch wind tunnel of the National Advisory Committee for Aeronautics. The tests were made at various velocities and it was found that the resistance of streamline wires was considerably less than that of round wires of equivalent strength. Scale effect was also found since, with an increase of Reynolds Number, a decrease in the resistance coefficient was obtained.
The resistance of three series of flying boat-hulls as affected by length-beam ratio
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Resistance of transparent plastics to impact
The problem of developing a windshield for aircraft which will withstand the effect of bird impacts during flight is a difficult one, as an estimate of the striking energy will indicate. If the average speed of the airplane is considered to be about 200 miles per hour and that of the bird about 70 miles per hour, the speed of the bird relative to the airplane may be as great as 400 feet per second. If a 4-pound bird is involved, a maximum impact energy of approximately 10,000 foot-pounds must be dissipated. To obtain this energy in a drop test in the Washington Monument, it would be necessary to drop a 20-pound weight down the 500-foot shaft. For both theoretical and practical reasons, it is necessary to keep the mass and speed more nearly like those to be encountered. However, to get an impact of about 10,000 foot-pounds with a 4-pound falling body, it would be necessary to drop it from a height of approximately one-half mile, neglecting air resistance. These facts will indicate some of the experimental obstacles in the way of simulating bird impacts against aircraft windshields.
Resistance of various materials to attack by molten bismuth-lead eutectic at elevated temperatures
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.
Resistance Tests of a L/L6 Size Model of the Hughes-Kaiser Flying Boat, NACA Model 183
Tank tests were made of a hull model of the Hughes-Kaiser cargo airplane for estimates of take-off performance and maximum gross load for take-off. At hump speeds, with the model free to trim, the trim and resistance were high, which resulted in a load-resistance ratio of approximately 4.0 for a gross load coefficient of 0.75. With a 4000,000-lb load, the full size craft may take off in 69 sec over a distance of 5600 ft.
Resistance tests of models of three flying-boat hulls with a length-beam ratio of 10.5
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The resistance to air flow of porous materials suitable for boundary-layer-control applications using area suction
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The resistance to air flow of porous materials suitable for boundary-layer-control applications using area suction
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The resistance to the steady motion of small spheres in fluids
There seems to be little reliable information conveniently available as to the resistance encountered by small spheres moving steadily at moderate speeds in fluids. The present paper, while presenting nothing new in the way of either theory or data, has three objects: first to show that published data are sufficient to furnish approximate information; second to present this information in form convenient for computation; and, third to indicate where further research is needed.
Resolution of annealing experiments for the study of nonequilibrium states
The two techniques for conducting annealing experiments for the purpose of determining the distribution of atoms of a solid among non equilibrium states are considered. Related definitions for resolving power for annealing with steadily rising temperature and for annealing at a series of fixed temperatures are given. The necessary separation of activation energies for the resolution of two different non equilibrium states is found to be greater in the case of a steadily rising temperature, but of the order of 10 percent of the activation energy for both techniques. The resolving power in the case of a steadily rising temperature is independent of the rate of temperature rise.
Resonance sound absorber with yielding wall
A single-sheet resonance system for normal incidence of sound was investigated to study in detail the effect of sympathetic vibration of the resonator front wall on sound absorption.
Resonance vibrations in intake and exhaust pipes of in-line engines III : the inlet process of a four-stroke-cycle engine
Using a previously developed method, the boundary process of four-stroke-cycle engines are set up. The results deviate considerably from those obtained under the assumption that the velocity fluctuation is proportional to the cylinder piston motion. The deviation is less at the position of resonance frequencies. By the method developed, the effect of the resonance vibrations on the volumetric efficiency can be demonstrated.
Resonance vibrations of aircraft propellers
On the basis of the consideration of various possible kinds of propeller vibrations, the resonance vibrations caused by unequal impacts of the propeller blades appear to be the most important. Their theoretical investigation is made by separate analysis of torsional and bending vibrations. This method is justified by the very great difference in the two natural frequencies of aircraft propeller blades. The calculated data are illustrated by practical examples. Thereby the observed vibration phenomenon in the given examples is explained by a bending resonance, for which the bending frequency of the propeller is equal to twice the revolution speed.
Resource Recovery from Municipal Solid Waste
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Resource Recovery Management Model: Overview
Abstract: This document provides an overview of the Resource Recovery Management Model which has been developed by the U.S. Environmental Protection Agency to assist regional, state, and local officials in developing plans, reaching decisions, and managing and conducting procurements for resource recovery facilities and services.
Respiratory Protective Devices Approved by the Bureau of Mines as of December 31, 1968: A Revision of Information Circular 8281
Report issued by the U.S. Bureau of Mines discussing a revision on the breathing devices approved for use in mines and mineral industries. As stated in the abstract, "this publication lists the respiratory protective devices approved by the Bureau of mines as of December 31, 1968, and the names and addresses of their manufacturers" (p. 1). This report includes tables.
Response of a helicopter rotor to oscillatory pitch and throttle movements
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Response of a Rotating Propeller to Aerodynamic Excitation
The flexural vibration of a rotating propeller blade with clamped shank is analyzed with the object of presenting, in matrix form, equations for the elastic bending moments in forced vibration resulting from aerodynamic forces applied at a fixed multiple of rotational speed. Matrix equations are also derived which define the critical speeds end mode shapes for any excitation order and the relation between critical speed and blade angle. Reference is given to standard works on the numerical solution of matrix equations of the forms derived. The use of a segmented blade as an approximation to a continuous blade provides a simple means for obtaining the matrix solution from the integral equation of equilibrium, so that, in the numerical application of the method presented, the several matrix arrays of the basic physical characteristics of the propeller blade are of simple form, end their simplicity is preserved until, with the solution in sight, numerical manipulations well-known in matrix algebra yield the desired critical speeds and mode shapes frame which the vibration at any operating condition may be synthesized. A close correspondence between the familiar Stodola method and the matrix method is pointed out, indicating that any features of novelty are characteristic not of the analytical procedure but only of the abbreviation, condensation, and efficient organization of the numerical procedure made possible by the use of classical matrix theory.
The response of an airplane to random atmospheric disturbances
The statistical approach to the gust-load problem, which consists in considering flight through turbulent air to be a stationary random process, is extended by including the effect of lateral variation of the instantaneous gust intensity on the aerodynamic forces. The forces obtained in this manner are used in dynamic analyses of rigid and flexible airplanes free to move vertically, in pitch, and in roll. The effect of the interaction of longitudinal, normal, and lateral gusts on the wind stresses is also considered.
The response of an airplane to random atmospheric disturbances
The statistical approach to the gust-load problem which consists in considering flight through turbulent air to be a stationary random process is extended by including the effect of lateral variation of the instantaneous gust intensity on the aerodynamic forces. The forces obtained in this manner are used in dynamic analyses of rigid and flexible airplanes free to move vertically, in pitch, and in roll. The effect of the interaction of longitudinal, vertical, and lateral gusts on the wing stresses is also considered.
Response of Deep Two-Way-Reinforced and Unreinforced Concrete Slabs to Static and Dynamic Loading, Report 3: Static Tests of Deep Slabs Having a Span-to-Thickness Ratio of 4.12
Partial abstract: "The objective of the investigation reported herein was to obtain laboratory response data for deep, two-way-reinforced and plain concrete slabs subjected to static overpressures in order to determine the response analysis necessary to analyze the target vulnerability of such structures under both active and passive defense situations" (p. 4).
Response of Dual-Purpose Reinforced-Concrete Mass Shelter
Response of helicopter rotors to periodic forces
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Response of homogeneous and two-material laminated cylinders to sinusoidal environmental temperature change, with applications to hot-wire anemometry and thermocouple pyrometry
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The response of pressure measuring systems to oscillating pressures
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