bluuebunny/crossref_metadata_2025 huggingface dataset:
The Gas Turbine as a Stationary Prime Mover
Authors: Rowley L. N. , Skrotzki B. G. A.
Published: December 2022

To date more than a score of stationary gas turbines, aggregating well over 100,000 kw, have been built or are under construction. About three quarters of these might properly be classed as commercial units. All the plants in this category operate at modest inlet temperatures and utilize alloy materials on which extensive experience has been obtained. This indicates definite places in the stationary power field for gas turbines such as can be built today under essentially commercial conditions. It seems evident that if the gas turbine is to move ahead as fast as its proponents desire, engineering effort and ingenuity comparable to that now going into technical development must be expanded on defining and evaluating the gas turbine’s economic possibilities so they may be fully exploited. This paper presents some preliminary thinking along these lines. For the case where power generation is the sole requirement, the authors analyze several specific situations. It must be clearly understood that such analyses are instructive only if their limitations are recognized; nothing is more dangerous than economic generalization. For cases where process heat as well as power must be supplied, the economic problem is even more complex. The authors have, of necessity, approached this question from a qualitative viewpoint, and merely indicate the general position of the gas turbine in this field and some of the modifications that might enhance its usefulness.
Experimental Determination of Velocity of Sound in Superheated Steam by Ultrasonics
Authors: Woodburn James
Published: December 2022

This paper describes apparatus which has been constructed for determining the velocity of sound in superheated steam. A quartz crystal, vibrated electrically at its natural frequency, is used as a sound source to set up a series of standing waves in a vertical cylinder filled with steam. The frequency of the sound source and the length of the standing waves are measured with high accuracy by simple and convenient methods. Experimental results are presented which show close agreement with data calculated from the steam tables of Keenan and Keyes.
Response Characteristics of Thermometer Elements
Authors: Hornfeck A. J.
Published: December 2022

Speed of response of the thermometer element is an important factor in the accurate measurement and control of temperature for industrial processes. This paper discusses the significance of the time constant as a basis of comparison of elements and shows quantitatively by means of data and curves the effects of varying the design factors such as socket size, materials, and internal element structure. The relation between the heat-transfer rate from the surrounding medium to the socket wall and the element response is shown by response data for a number of designs tested in air and water. Methods are given for determining the temperature versus time response curves of elements in a medium whose temperature is changing suddenly, uniformly, and sinusoidally as a function of time.
Field Control of Oil-Field Pumping Equipment
Authors: Gregory J. N.
Published: December 2022

The conditions faced by an oil producer in accomplishing continuous operation of surface pumping equipment without frequent attendance are outlined. The construction and application of devices to perform routine services on oil-well pumping equipment are described, and particular attention is directed toward eliminating the services which ordinarily must be performed at frequent intervals. The need for a preventive maintenance program is outlined and the instruments and tools which may be used in such a program are explained. Certain devices for use at problem wells are discussed, and the value of operating procedures which consider routine service, preventive maintenance, and corrective measures is indicated.
Tests on V-Belt Drives and Flat-Belt Crowning
Authors: Norman C. A.
Published: December 2022

The investigations here reported were undertaken with the liberal support of the Goodyear Tire and Rubber Company, at the instigation of the company’s well-known belt engineer, the late Mr. Ray S. Carter. The immediate reason for the investigation was the desire to clear up under just what tension the front-end belt drives on certain important automotive vehicles ought to be applied to insure dependable power transmission even under sustained heavy load, and yet insure a reasonable belt life. These drives involve high speeds, small contact angles, and also small pulley diameters. Hence it was necessary to clear up the influence of contact angle on transmissive power with the small pulley diameters used. Also belt-life determinations were in order. The project then involved, in fact, all the fundamentals of power transmission with modern V-belts. While the work was in progress Mr. Paul D. Suloff, who throughout maintained current liaison between the company and the experimenters, suggested that the effectiveness of pulley crown on modern flat belts should be investigated, since with these belts customary crown practice might not be salutary for the belt. Such investigations were then added to the program. In September, 1945, the project suffered a very serious loss in the death of Mr. Carter at the height of his powers and usefulness. The work, however, continued under the detail supervision of Mr. Suloff as before, and by the spring of 1946, it was felt that the fundamentals had been determined; but for one belt size only. Experiments on other belts continued into 1947, at which time it was necessary for the author to curtail his activities. This made it impossible to give a complete experimental answer to the practical question originally posed by Mr. Carter. However, so much fundamentally important material had been accumulated that a delay in making it available to belt users would not seem justifiable. Supplementary tests (see p. 347) extend the findings to higher loads and speeds.
Investigation of Variation of Point Unit Heat-Transfer Coefficient Around a Cylinder Normal to an Air Stream
Authors: Giedt W. H.
Published: December 2022

Most previous analytical and experimental work concerned with the variation of the rate of heat transfer around a cylinder normal to an air stream has been confined to one with an isothermal surface. It was therefore the purpose of the investigation described in this paper to obtain information on the variation of the rate of heat transfer around a cylinder with a nonisothermal surface. The method was suggested by a technique used in flight tests for determining point unit heat-transfer coefficients around airfoils. A thin nichrome ribbon wound helically around a cylinder was electrically heated. Point unit heat-transfer coefficients were determined from the temperature variation along, and electrical input to the ribbon. Results indicated the method would also be suitable for similar measurements around other streamlined shapes. The experimental data include point unit heat-transfer coefficient and static-pressure distributions around a cylinder circumference throughout a range of Reynolds modulus from 70,800 to 219,000. Comparison of these results with the skin-friction distributions around the cylinder indicated by the pressure distributions showed a definite correlation between the two. Results are also compared with those obtained by other investigators using an isothermal cylinder surface.
A Classification of Linear Transfer Members
Authors: Mason H. L.
Published: December 2022

Linear dynamic behaviors are here grouped in a classification consisting of four basic curves with three methods of modification and two methods of combination. It depends on responses to unit step disturbance, and relates to Laplace transforms. Its utility is shown for members sequenced, manifolded, or looped, also for arbitrary disturbances and for reflex action.
Correlation of Performance Characteristics of Domestic-Stoker Coals With Their Chemical and Petrographic Composition
Authors: Helfinstine R. J. , Cady G. H.
Published: December 2022

There is a definite need for information about the value of chemical and petrographic analyses in predicting the behavior of stoker coals in domestic stokers. In order to obtain this information in our Illinois studies, performance characteristics of a large number of coals were determined and correlated with the various items of the proximate and ultimate analyses, heating value, varieties of sulphur, ash analysis, ash-fusion temperatures, free-swelling index, petrographic analysis, and Gieseler plasticity. A brief report on the results, including some graphs of the more useful correlations, are given.
Marine Propulsion-Gear Testing at the Naval Boiler and Turbine Laboratory
Authors: Monk Ivan
Published: December 2022

This paper describes the testing phases of the propulsion-gear development program of the United States Navy. Full-sized reduction-gear units are tested to destruction under controlled conditions. The facilities and procedures employed in these tests are described, together with some of the problems encountered. Results are presented from tests in which four destroyer-escort reduction-gear units were able to transmit more than three times their designed full power before failure occurred.
Involute-Gear Geometry: Nondimensional Analysis and Design of Tooth Forms, Tooth Thickness, and Mesh Relationships
Authors: Grosser C. E.
Published: December 2022

Definition and discussion of recently discovered fundamental gear characteristic called “belt-length ratio,” to simplify gear design and generation computations, are given with necessary measurement procedures, formulas, and a graphical calculating chart. The concepts and methods are proposed as alternatives to use of conventional involute-function tables and formulas. Relationships are given in nondimensional (ratio) form so that a minimum of data are applicable to all gear sizes. A new standard for pin measurements of gears and involute splines is suggested.
Power-Plant Cycle Evaluation
Authors: Salisbury J. K.
Published: December 2022

Thermodynamic losses in the heater system of a steam-power-plant cycle are analyzed. All heater systems are rated with respect to an “ideal” heater system. Simple algebraic formulations permit determination of arrangement loss, distribution loss, and loss due to terminal difference and pressure drop in any heater cycle. Miscellaneous corrections to cycle heat rate are described and two typical corrections are analyzed. The paper constitutes a new fundamental approach to analysis of feedwater heating cycles, based largely upon a simplifying assumption, valid for the purpose. It may be regarded as a sequel to a previous paper covering major parameters of steam-plant regenerative cycles.
Hot-Spin Tests of Bladed Jet-Engine Rotors
Authors: Saldin H. B. , DeHuff P. G.
Published: December 2022

The creep-rupture and ductility characteristics of materials are of utmost importance to the designer of high-temperature rotating parts. The authors have pointed out the significance of ductility of materials used for gas-turbine disks. Four-bladed disks were tested in a facility that was designed to spin the rotors in as near engine operating conditions as possible. These parts were tested in accordance with a predetermined schedule of temperature gradient, temperature, and speed. Test results are analyzed, and a discussion of the advantages and the design of such a facility is also included.
Developments in Resuperheating in Steam Power Plants
Authors: Harris E. E. , White A. O.
Published: December 2022

Both steam and gas reheaters have been used for a number of years, and this paper is devoted to a discussion and evaluation of the gains in thermal efficiency as reflected in turbine heat rate realizable in modern steam turbines for central stations. The gains due to reheat are justified economically with present equipment and fuel costs. They represent an additional gain in fuel economy over and above the normal annual gain.
Steam Turbines for Resuperheat Cycle
Authors: Parker E. E.
Published: December 2022

Resuperheat cycles are again being applied to central-station steam-turbine installations; this time at initial and reheat temperatures in the range of 950 to 1050 F. This paper reviews the steam turbines installed by the author’s company for the resuperheat cycle and describes the modern turbines under construction for this cycle.
Steam-Generating Equipment for Resuperheating Cycles
Authors: Frisch Martin
Published: December 2022

This paper examines some of the technical and operating problems which must be faced in the selection of equipment to supply steam to high-pressure turbine-generating equipment employing steam resuperheated to high temperatures in the low-pressure section. The costs of steam-generating equipment per kilowatt of turbine-generator capability for resuperheating cycles are compared with costs of equipment for cycles which do not employ resuperheating. The effects on equipment costs, of furnace-exit temperature limitations imposed by fuel quality and load range over which primary and resuperheated steam temperatures must remain constant, are examined in detail. Data are presented comparing present-day prices of steam-generating equipment per kilowatt of turbine-generator capability for several high-temperature and high-pressure resuperheating and nonresuperheating cycles usually employed in power stations.
Critical Flow Through Sharp-Edged Orifices
Authors: Perry J. A.
Published: December 2022

An investigation was made to discover the flow rates of air through sharp-edged orifices in which the pressure drop was below the critical; the relationship of pressure, temperature, and orifice area; and a comparison between the nozzle and the orifice. Equations are derived for expressing orifice flow in both the critical and subcritical regions.
The Instron Tensile Tester
Authors: Hindman Harold , Burr G. S.
Published: December 2022

A new type of tensile-testing instrument is described, utilizing electronic principles for both the weighing of the forces on the sample and for controlling its extension. This instrument was designed with the idea of controlling these time functions accurately, and in so far as possible, of preventing the characteristics of the machine from obscuring the accuracy of the results.
Heat Transfer to Water at High Flux Densities With and Without Surface Boiling
Authors: Kreith Frank , Summerfield Martin
Published: December 2022

Surface coefficients of heat transfer have been obtained at rates of heat flux up to 3 Btu/ (sq in.)(sec) for water flowing in stainless-steel tubes at mass-flow rates up to 5.4 lb per sec-sq in. The nonboiling forced-convection data were correlated by the Colburn equation Nuf = 0.023 Ref0.8Prf1/3 within ±5 per cent, but, with surface boiling, considerably larger Nu moduli were observed. When surface boiling occurred, the wall temperature was determined primarily by the pressure, being relatively insensitive to variations in velocity, heat flux, and bulk temperature. The maximum heat flux that could be removed under given conditions was limited by an unsteady-flow phenomenon. Data for pressure drop with and without nonboiling heat transfer are presented and correlated by an empirical viscosity correction factor.
The Mechanical Cleaning of Fouled Heat-Exchanger Tubes
Authors: John A.
Published: December 2022

For many years in the past, mechanical cleaning of badly fouled heat-exchanger tubes was more or less done on an improvised basis. As heat exchangers began to be extensively used, fouling became a problem of major and varied proportions. This created an impetus for the tube-cleaning industry to concentrate on the development of a special tool for this purpose. Today, there is available to the trade a single-purpose mechanical cleaner suitable for almost every possible tube-cleaning requirement, as the author explains in this paper.
Scale Formation and Control in Compression Distillation of Sea Water
Authors: Campobasso J. J. , Latham Allen
Published: December 2022

Various principles which have been used to combat the formation of scale in sea-water distillation equipment are outlined briefly. Data on the rate of scale formation in the compression type of distillation unit are presented. Results obtained by periodic chemical cleaning and low-temperature operation are discussed.
Viscosity and Other Physical Properties of Gases and Gas Mixtures
Authors: Hirschfelder J. O. , Bird R. B. , Spotz Ellen L.
Published: December 2022

This paper is of special importance to the engineer because it is perhaps the first attempt to present directly a comprehensive review of the theoretical tools available for the calculation of the thermodynamic properties of gases and gas mixtures at finite, if only moderate pressures. The paper reviews a mass of information collected during the past two decades and shows the extent to which it can be correlated and systematized by means of molecular theory. The paper goes further to outline a new and apparently very successful method of formulating and predicting the viscosity and other transport properties of gases and gas mixtures at sufficiently low pressures. The method is the first significant practical improvement over the relatively crude one developed by Sutherland, and it is almost certain that engineers will find it extremely useful once they come to understand it. The extensive tables which are vital to the paper not only illustrate the method but implement it as well so that the user is enabled to calculate the viscosity and other transport properties of a large class of technically important gases and gas mixtures with very little labor.
Chrysler Multibank Power Plant for Medium Tanks
Authors: Woolson H. T.
Published: December 2022

In July, 1941, an emergency message came to the Chrysler management from high authority in Washington which was in essence, “What can you do to give us medium tank engines in a hurry?” Engineering consideration was immediately given to the problem. The first thought, was naturally in the direction of a new suitable design. The time factor, however, eliminated such a project. A possible solution suggested was to use in multiple, an automobile or truck engine which had had a background of years of successful operation and which could be made with the company’s existing tools.
Cadillac Twin V-8 Power Plant for Light Tanks
Authors: Gordon J. F.
Published: December 2022

The substitution of twin Cadillac engines for a single radial-type tank engine resulted in the new model M-5 light tank. This adaptation was followed by a succession of tanks, howitzers, mobile artillery carriages, personnel carriers, and landing vehicles which used the same basic power-train idea. The co-operative engineering program with other contractors, test procedures necessary to validate new designs, and the value of “emergency” engines to the Service Forces have been outlined in the paper.
The Application of Wood and Fiber to Industrial Packing
Authors: DeLuca J. A.
Published: December 2022

To satisfy the varying conditions of service a number of well-defined types of containers, such as nailed wooden boxes, crates, fiber boxes, barrels, baskets, drums, plywood boxes, and wire-bound boxes, have been developed. Each of these, because of the varying nature of its design and the materials of its construction, fulfills some particular purpose better than the others. In selecting a type of container for a specific purpose, it should be remembered that what constitutes a weakness in a container for one commodity may be an advantage for another commodity. The characteristic strength and weakness of several types of boxes and crates and the construction details influencing their serviceability are discussed in the paper.
Measurement of the Viscosity and Shear Elasticity of Liquids by Means of a Torsionally Vibrating Crystal
Authors: Mason W. P.
Published: December 2022

This paper describes a method of measuring viscosities of liquids at high-frequencies by means of oscillating cylinders, in which a torsionally vibrating crystal generates a viscous wave in the medium to be measured. Both a reactance and a resistance loading occur in the crystal which lowers its frequency and raises the measured resistance at resonance. The viscosity may then be determined by measuring the changes in the properties of the crystal. By varying the voltage on the crystal, the shearing displacement can be varied and hence the viscosity can be measured as a function of shearing stress. Measurements on light oils over a viscosity range from 0.01 poise to 10 poises check within a few per cent when made with rough temperature-control conditions.
Performance of Vertical Water Wheel Thrust Bearings During the Starting Period
Authors: Laffoon C. M. , Baudry R. A. , Heller P. R.
Published: December 2022

The modern thrust bearing which has made the huge vertical hydroelectric unit possible is primarily recognized as an application of the hydrodynamic theory of lubrication. At normal speeds the bearing surfaces are separated by a film of oil so that wear is effectively eliminated. During the starting period, however, there is metal-to-metal contact under high thrust loads. The performance of the bearing is then extremely complex, being dependent on adequate surfaces and lubricants. The advent of methods of measuring the roughness of machined parts has facilitated the development of better bearing surfaces while many tests, both in the laboratory and in the field, have contributed to a better knowledge of the required surface finish, oil properties, and starting temperatures.
Corrosion-Erosion of Boiler Feed Pumps and Regulating Valves
Authors: Wagner H. A. , Decker J. M. , Marsh J. C.
Published: December 2022

Seven 500-hr corrosion-erosion tests, involving a total of eighteen different materials, were conducted at the Marysville power plant of The Detroit Edison Company to determine the resistance of these materials to the corrosion-erosion type of attack experienced in boiler feed pumps and regulating valves. Two of these tests were for the purpose of verifying the pressure differential used. The other five tests indicated that resistance to corrosion-erosion is materially increased by using chromium-bearing alloy steels. Bronzes and monel are resistant to attack and, to a lesser extent, so is cast iron. Results obtained with a bakelite-lacquer-coated carbon-steel specimen indicated that this coating has considerable promise for use with present boiler feed pumps having cast-carbon-steel casings. The test used is of an accelerated type intended to simulate conditions in actual pumps and valves.
Determination of Moisture Content of Coal by Means of Pulverizer Heat Balance
Authors: Finnegan T. J. , Smith H. L.
Published: December 2022

The customary coal-sampling methods, by hand or by mechanical means, are notably tedious and lacking in accuracy. Since all plant-performance calculations, which are made from the “as-fired” heating value, depend for their accuracy upon that of the reported moisture content of the coal, it is desirable to determine the true average value of that moisture for the operating period under consideration. In a direct-fired pulverized-coal installation, the coal may be sampled for the dry-basis analysis, and the raw-coal moisture, which is to be used for converting this to the as-fired basis, may be determined by the primary-air temperature. This paper describes how this method was developed for use at one station.
Creep, Long-Time Tensile and Flexural Fatigue Properties of Melamine and Phenolic-Plastics Materials
Authors: Telfair D. , Adams C. H. , Mohrman H. W.
Published: December 2022

This paper reports work done to compare the tensile creep, long-time tensile strength, and dynamic flexural fatigue-strength properties of some commercial melamine and phenolic-plastic materials. Tensile-creep data for woodflour-filled phenolic and cellulose-filled melamine indicate that these plastics exhibit similar characteristics, that is, the rate of elongation at 500 hr is essentially the same for the two materials. Likewise, the total elongation at 1000 hr is of the same order of magnitude for each of the materials. Similarly, asbestos-filled phenolic and asbestos-filled melamine show comparable tensile-creep properties. The long-time tensile strength of the cellulose-filled melamine is superior to that of the woodflour-filled phenolic material. The melamine has a long-time tensile strength of about 67 per cent of the short-time value (A.S.T.M. D638-41T), as compared with a value for the phenolic of approximately 36 per cent. Results of the repeated flexural-stress tests indicate that the woodflour-filled phenolic plastic is slightly superior to the cellulose-filled melamine, the endurance limit for the phenolic being approximately 4000 psi, or 34 per cent of the short-time static flexural strength, and for the melamine 3000 psi or 31 per cent of the short-time static flexural strength. Further tests of this nature would be desirable for the purpose of studying the effect of other fillers and formulations.
Laboratory Testing of Rubber Torsion Springs
Authors: Cornell D. H. , Beatty J. R.
Published: December 2022

The cylindrical rubber torsion spring consists of three essential members — an intermediate member of flexible rubber, securely bonded to two rigid cylindrical metal shells, forming concentric inner and outer members. If such a spring is stressed in torsional shear, many advantages are realized, such as versatility of design, no static friction, inherent stability, elimination of serious stress concentrations, and elimination of lubrication needs. Laboratory tests have been performed to establish the load-deflection modulus, creep, and fatigue properties of rubber torsion springs. Other work has been done to a limited degree to investigate the effect of temperature on all of the properties mentioned. Such a program necessitated the development of test methods for these particular investigations. Methods have been developed to find accurately and conveniently the static and dynamic moduli of any rubber torsion spring if its physical dimensions and the fundamental data of the rubber are known.
Damping of Textile-Mill Movement by Frahm System
Authors: Crede Charles E.
Published: December 2022

One of the most prevalent vibration problems in the operation of textile mills is associated with the lay movement of looms. The lay is a relatively heavy member driven with a reciprocating motion in essentially a horizontal path. Harmonic inertia forces are set up, and with the simultaneous operation of many looms large forces are transmitted to the floor and. thence to the walls of the building. Particularly where looms are mounted on upper floors of a mill building, the consequent side-to-side swaying movement is liable to exceed proportions of safety to the structure. In some cases, looms have been moved to lower floors, and in others remedial steps have been taken. Such remedies have taken the form of external abutments to reinforce the walls; the speeds of a number of looms have been changed to reduce the duration of the in-phase periods; and looms have been reoriented to distribute the forces in several different directions. Some of these measures have been helpful but not entirely corrective. The approach described in this paper is to apply to the Frahm tuned vibration damper to the restraint of mill movement.
Test Data on Gas-Side Sulphate-Type Deposits on Tubes Beyond Boiler Furnace
Authors: Barkley J. F. , Burdick L. R. , Berk A. A.
Published: December 2022

Owing to accumulations of troublesome deposits on the gas side of tubes in one of the boilers at the Naval Gun Factory in Washington, a thorough study of the formation of the deposits was undertaken. From this work an improved method of analyzing products of combustion for SO2 and SO3 content was developed, details and procedure for which are given in the paper.
Cross-Laminated Oak
Authors: Stern E. George
Published: December 2022

Three-ply cross-laminated oak panels with oak or yellow-poplar core of 25/32 or 1¼ in. total thickness, and 7 × 7 in., or 12 × 12 in. in area, were subjected to exposure tests of repetitive and/or alternating drying at slightly below 100 C, and/or soaking at laboratory temperature for 48 hr, in order to determine the influence of internal stresses due to exposure on the dimensional stability and durability of such panels. The test results indicate that these panels can be cross-laminated satisfactorily to with-stand extreme exposure conditions such as may occur in service, if their cross sections are properly balanced and their plies are properly assembled. The Tennessee Valley Authority designed and built a continuous-press pilot plant for the production of these 12-in-wide panels of any desirable length.
Stress Notch Sensitivity With Eccentric Holes
Authors: Schapiro L. , Esling R. H.
Published: December 2022

The tension strength of several cross sections containing holes of several diameters in several positions of eccentricity have been determined experimentally for aluminum alloys 24S-T, 75S-T, and 14S-T. A mathematical expression is suggested for the relationship between strength, hole size, and eccentricity of hole. The relative stress notch sensitivity of the three aluminum alloys is found to be the same with eccentric holes as had been reported for central holes or external notches.
Effect of Some Processing Variables on the Stress Required to Draw Tubular Parts
Authors: Espey George , Sachs George
Published: December 2022

Tubular brass parts were drawn to determine the effects of a number of variables upon the draw forces and stresses. The variations were in the tube dimensions, the contour and finish of the die and punch, the temper and surface condition of the tubular parts, and the lubricant. The draw stress for a given reduction increased with decreasing die angle, this being the most important die variable. Radiused dies behaved in a manner similar to conical dies of the same contact area. Other die variables investigated had little effect upon the draw stress, these being various lengths of the cylindrical portion of the die at the exit (bearing or land), the die material, and the die finish. Tests with tapered punches yielded results similar to those obtained with cylindrical punches. Experimentation with punches of various degree of finish revealed that rough punches gave higher draw forces than polished punches, particularly when used in conjunction with small-angle dies. A number of lubricants were investigated, none of which excelled the performance of a 2 per cent aqueous solution of soap. The draw stresses were found to decrease with increasing time of immersion in soap solution.
The 2000-Psi, 1050 F, and 1000 F Reheat Cycle at the Philip Sporn and Twin Branch Steam-Electric Stations
Authors: Sporn Philip
Published: December 2022

The economical generation of steam-electric energy is affected by such factors as site, fuel, cycle, and equipment. A discussion of these basic factors serves as introduction to a description of the program involving the addition of 525,000 kw of generating capacity to the Central System of the American Gas and Electric Company at the Tidd, Philip Sporn, and Twin Branch Steam-Electric Stations. The discussion of the design employing 2000-psi 1050 F initial temperature with 1000 F reheat at the Philip Sporn Plant includes the location of the plant on the system, features of the site, the heat cycle, turbine, boiler, and plant layout. A net plant heat rate of 9270 Btu per net kwhr output is expected.
Gas-Turbine Plant Combustion-Chamber Efficiency
Authors: London A. L.
Published: December 2022

Concepts of gas-turbine plant combustion-chamber efficiency are considered. Three distinct efficiency terms are required, one applying to incomplete combustion and setting losses, one to the flow friction and auxiliary-drive energy requirements, and the third to the influence of these losses on over-all plant thermal efficiency and output. These efficiencies are defined and details of application indicated. The proposed concepts are recommended for consideration as standards since they are thermodynamically meaningful, unambiguous, and relatively easy to apply both in evaluation of test performance and in cycle analysis.
Temperature Measurements and Combustion Efficiency in Combustors for Gas-Turbine Engines
Authors: Olson Walter T. , Bernardo Everett
Published: December 2022

In investigations of the general altitude performance of combustors for aircraft gas-turbine engines at the Cleveland laboratory of the National Advisory Committee for Aeronautics (NACA), the combustors have been instrumented with a large number of thermocouples for determining average temperatures, temperature distributions, and combustion efficiencies. Presented herein is a discussion of the thermocouple installations used, some of the construction details of typical thermocouples, and representative temperature and combustion-efficiency measurements made in combustors. The results of numerous investigations of the general altitude performance of combustors for gas-turbine engines have indicated that air temperatures at the inlet to the combustors can be adequately measured with common bare-wire thermocouples, and that, at the combustor outlet, large variations in temperature distributions, nonuniform velocity distribution, and fluctuations in the temperatures are among the possible sources of errors in measuring the average combustor-outlet temperatures. In addition, the results indicate that the temperatures measured at the combustor outlet, although admittedly not accurate, are generally satisfactory for evaluating the altitude performance of combustors, and that the values of combustion efficiencies obtained from temperature measurements are satisfactory approximations of combustion efficiencies and serve to show the effect of primary variables on combustion efficiency.
Furnaces for By-Product Fuels
Authors: de Lorenzi Otto
Published: December 2022

Present-day costs of standard fuels such as coal, oil, and gas have advanced to a high level and concepts must now be revised regarding so-called refuse fuels. Their value as low-cost substitute fuels, for steam generation, will depend largely upon the manner in which they are prepared, and upon the use of suitable furnace designs. A number of furnace designs have been developed to handle by-product fuels from oil-refinery operations, and the manufacture of steel, coke, lumber, pulp, and sugar. Others are still in various experimental stages and many improvements in methods of drying, feeding, and burning fuels will be presently available. The characteristics of several of these fuels are discussed, and actual furnace designs illustrate the manner in which they are fired to provide process steam and save fuel dollars.
Laboratory Investigations of the Mechanism of Cavitation
Authors: Knapp R. T. , Hollander A.
Published: December 2022

The paper describes some experimental investigations of the formation and collapse of cavitation bubbles. The experiments were carried on in the high-speed water tunnel of the Hydrodynamics Laboratory of the California Institute of Technology under the sponsorship of the Research and Development Division of the Bureau of Ordnance of the U. S. Navy and the Fluid Mechanics Section of the Office of Naval Research. A detailed study of the formation and collapse of the individual bubbles has been carried on by the use of high-speed motion pictures taken at rates up to 20,000 per sec. From these records calculations have been made of rate of formation and collapse of the bubbles. Deductions have been drawn from these results concerning the physical mechanism of the cavitation phenomenon.
Frequency-Response Measurements of a Hydraulic Power Unit
Authors: Hannah M. R.
Published: December 2022

Hydraulic power units continue to find important applications in a wide variety of servomechanisms wherein high-performance power sources are required. In such applications the servo designer is concerned with the fidelity of the power unit in responding to the controlling signals, and this information is often obtained or corroborated by means of experimental data. This report outlines an investigation into the dynamic response of a typical hydraulic power unit comprising a transmission and associated stroke control. The well-known tool of frequency analysis has been employed to investigate the effects of certain system parameters on the performance of the several components of the power unit. The results have been evaluated with a view toward effecting improvement in the response of the power unit as a whole.
Prediction of Pressure Drop During Forced-Circulation Boiling of Water
Authors: Martinelli R. C. , Nelson D. B.
Published: December 2022

A tentative method for the rapid calculation of the pressure drop during forced-circulation boiling of water is presented. The method is based upon the application of pressure-drop data, obtained during the isothermal flow of air and various liquids, to the evaluation of local pressure gradients during forced-circulation boiling. Curves are developed by means of which the pressure drop during boiling can be estimated quickly once the exit quality, the boiling pressure, and the pressure drop for 100 per cent liquid are known. The proposed method is definitely an extrapolation of existing data and, as such, requires further experimental verification.
Experimental Combustion of Pulverized Coal at Atmospheric and Elevated Pressures
Authors: Hazard H. R. , Buckley F. D.
Published: December 2022

Among the basic problems associated with the development of a gas-turbine plant to use pulverized coal are those related to the burning of the pulverized coal under gas-turbine conditions. These conditions include high heat-release rates, high excess air, high static pressures, and a wide range of variation in all operating conditions. No previous data indicating the effects of pressure on the reaction rate of pulverized coal were available at the start of this investigation, and there had been little occasion to burn pulverized coal at the high heat-release rates used in gas-turbine practice when burning liquid fuels. This paper presents results obtained in a study of the effect of pressure upon the combustion reaction, and describes tests made with four small air-cooled combustors operated at high heat-release rates and low pressure in connection with a small gas-turbine unit. The work described was sponsored by the Locomotive Development Committee of Bituminous Coal Research, Inc., under J. I. Yellott, director of research. It was one of several projects, related to the development of the coal-burning gas-turbine locomotive, which have been assigned to a number of universities and research institutions, and which have been described by Yellott in a recent paper. At the present time, large-scale development work is under way both at Battelle, where full-scale atmospheric-pressure combustors are under test, and at the Dunkirk, N. Y., plant of the American Locomotive Company, where full-scale coal-preparation equipment is being operated with a ⅓-scale combustor at full pressure.
Energy-Temperature Relations in the Combustion of Fuels in Gas Turbines
Authors: Kleinschmidt R. V.
Published: December 2022

In this paper, the author discusses procedures for evaluating energy, temperature, and pressure relations based on precise knowledge of thermodynamic properties of the gases resulting from the combustion of fuel in thermal devices, including gas turbines. The problem of computing thermal efficiency and fuel required to cause a given temperature rise in the working fluid of a gas turbine is discussed.
Further Investigation on the Graphitization of Piping for the EEI and AEIC
Authors: Hall A. M. , Hoyt S. L.
Published: December 2022

The graphitization test program initiated in 1943 at Battelle Memorial Institute by the EEI and AEIC was continued during 1947. Carbon-molybdenum, chromium-molybdenum, and vanadium-molybdenum compositions were tested at 1125 F. An effort was made to relate plastic deformation with graphitization on a laboratory basis. The high resistance of chromium-molybdenum steels was confirmed and further information was developed on the existence of an incubation period in the graphitization process.
Oscillating-Piston Meters for Fuel Consumption in Aircraft
Authors: Hazard C. S.
Published: December 2022

The amount of fuel remaining in the tanks of an airplane in flight may be determined in two ways: (a) by measuring the liquid levels in the tanks; or (b) by measuring the fuel as it is consumed and subtracting from the amount on board at take-off. The oscillating-piston type of displacement meter has been used successfully in the latter system. This paper describes two such meters, and gives data on the accuracy of this method of fuel measurement.
Analysis of Heat Transfer Over a Small Cylinder in Icing Conditions on Mount Washington
Authors: Tribus Myron , Young G. B. W. , Boelter L. M. K.
Published: December 2022

The data reported by Schaefer (1) for the heat required to maintain a heated rod (Calrod) dry and with a small trace of ice are compared to the heat requirements determined analytically. Satisfactory agreement (within the limits of the simplifying assumptions) was obtained for the first case only. Discrepancies between experimental and computed results are discussed. A new design for the heated cylinder is proposed as a possible means of measuring liquid-water content and drop size in flight through clouds.
Radiative Heat Transfer in Turbulent Combustion 2021 Max Jakob Memorial Award Paper
Authors: Modest Michael F.
Published: December 2022

In many important combustion applications, heat transfer is dominated by thermal radiation from combustion gases and soot. Thermal radiation from combustion gases is extremely complicated, and accurate and efficient predictions are only now becoming possible with the use of accurate global methods, such as full-spectrum k-distributions, and with state-of-the-art line-by-line accurate Monte Carlo methods. The coupling between turbulence and radiation can more than double the radiative loss from a flame, while making theoretical predictions vastly more complicated. This paper is an embellished version of the 2021 Max Jakob Award lecture: Radiative properties and computational methods will be briefly discussed, and several examples of turbulent reacting flows, an oxy-fuel furnace, and high-pressure fuel sprays in combustion engines will be presented. Thermal radiation can also be used as an optical diagnostic tool to determine temperature and concentration distributions, which will be briefly discussed.
A dialog on the fate of information in black hole evaporation
Authors: Perez Alejandro , Sudarsky Daniel
Published: December 2022

We present two alternative perspectives for the resolution of Hawking's information puzzle in black hole evaporation. The two views are deeply contrasting, yet they share several common aspects. One of them is the central role played by the existence of the interior singularity (whose physical relevance is implied by the singularity theorems of Penrose) that we expect to be replaced by a region described by a more fundamental quantum gravity formulation. Both views rely on the notion that the standard effective quantum field theoretic perspective would require some deep modifications. In this respect, both of our scenarios are deeply influenced by ideas that Penrose has advocated at various times and, thus, serves to illustrate the lasting influence that his deep thinking on these and related matters continues to have on the modern thinking about fundamental aspects of both quantum theory and gravitation. Despite that, there is of course no claim that Penrose would agree with any of the concrete proposals that will be discussed here.
Conformal chemical vapor deposition of boron-rich boron carbide thin films from triethylboron
Authors: Choolakkal Arun Haridas , Högberg Hans , Birch Jens , Pedersen Henrik
Published: December 2022

We report conformal chemical vapor deposition (CVD) of boron carbide (BxC) thin films on silicon substrates with 8:1 aspect-ratio morphologies, using triethylboron [B(C2H5)3] as a single source CVD precursor. Step coverage (SC) calculated from the cross-sectional scanning electron microscopy measurements shows that films deposited at ≤450 °C were highly conformal (SC = 1). We attribute this to the low reaction probability at low substrate temperatures enabling more gas phase diffusion into the features. The chemical state of the material, determined by x-ray photoelectron spectroscopy, shows as a carbide with B–B, B–C, C–B, and C–C chemical bonds. Quantitative analysis by time-of-flight elastic recoil detection analysis reveals that films deposited at 450 °C are boron-rich with around 82.5 at. % B, 15.6 at. % C, 1.3 at. % O, and 0.6 at. % H, i.e., about B5C. The film density as measured by x-ray reflectometry varies from 1.9 to 2.28 g/cm3 depending on deposition temperature.
Molecular layer deposition of alucone in high aspect ratio trenches: The effect of TMA outgassing on step-coverage
Authors: Jain Hardik , Creatore Mariadriana , Poodt Paul
Published: December 2022

Infiltration of trimethylaluminum (TMA) in molecular layer deposition-enabled alucone thin films on planar substrates is a common observation reported in the literature. An insufficient TMA purge time in such cases is often found to lead to a CVD component in the overall film growth due to the reactions between the outgassing TMA and the co-reactant. In this work, the effect of the CVD component on the step coverage of alucone films when grown in high-aspect ratio trenches is studied. The thickness was initially found to increase with increasing distance from the trench aperture before starting to decrease up to the film’s maximum penetration depth. With the support of modeling, the reason behind the observed thickness profile was investigated and attributed to the combination of an increasing outgassing rate of TMA and a decreasing ethylene glycol (EG) concentration along the trench depth. Furthermore, the maximum thickness and the position where it is obtained in the trench are found to depend on TMA and EG doses, TMA purge time, the trench height, and the trench depth. Finally, the possibility of adopting the additional CVD component in film growth for void-less gap fill of 3D trenches is discussed, as well as the suppression of the same CVD component, without compromising the growth rate, by using dimethylaluminum isopropoxide as a substitute for TMA is evaluated.