bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Spacing Between Dies in the Tandem Drawing of Tubular Parts
Authors: Sachs George , Espey George
Published: December 2022

In the drawing of tubular parts over a mandrel, several dies in tandem are often used to perform greater total reductions. The results of the investigation reported in this paper demonstrate the importance of a sufficiently large spacing when drawing tubular parts with a tandemdie arrangement. The total reductions achievable with a given spacing are a maximum if the first reduction is as close as possible to the maximum reduction obtainable with a single die. A spacing close to 3 times the diameter of the drawpiece will give substantially the same total reduction as two single draws for any tubular part having an initial wall thickness of less than 10 per cent of its diameter. For tubular parts having a very thin wall, the required spacing might even be smaller than 3 times the diameter.
Temperature Charts for Induction and Constant-Temperature Heating
Authors: Heisler M. P.
Published: December 2022

Charts are presented for determining complete temperature histories in spheres, cylinders, and plates. It is shown that for values of the dimensionless time ratio X greater than 0.2 the heating equations reduce to such a simple form that for each shape two charts which give temperatures at any position within the heated or cooled bodies can be plotted. It is also shown that the usual simple heating and cooling charts can also be used for the determination of temperatures and heating times in bodies heated by a constant rate of heat generation at the surface (induction heating). Finally, a two-dimensional chart is given for finding heating times in short cylinders, thereby eliminating the trial-and-error solution that is necessary when heating times are found from the present one-dimensional charts.
Investigation of Flow in Liquids by Use of Birefringent Colloidal Solutions of Vanadium Pentoxide
Authors: Ullyott Philip
Published: December 2022

The author, engaged on hydrological research on the Bosphorus (1) and interested in diffusion and turbulence as biological environmental factors, was first induced to try a flow-birefringence method on a macroscopic scale, as a result of reading a paper on the shape of protein molecules (2). The use of vanadium-pentoxide sols as a birefringent medium for the demonstration of fluid flow was so successful that Prof. J. C. Bliss, Dean of the Engineering School at Robert College, encouraged the author to write a preliminary publication emphasizing the possibility of engineering application. On account of the pressure of other work, the manuscript was not ready until the beginning of September, 1945. It appears that, unknown to the author, the method of flow birefringence has been in use for some time. In a recent article by Walter Leaf (3) the following statement is made: “This process was developed in the chemical-engineering department of the Massachusetts Institute of Technology by D. R. Dewey, 2nd, under the direction of Dr. E. A. Hauser about 4 years ago.” The process involves the use of the birefringent properties of bentonite clays (named from Fort Benton, Wyoming). Jerome Alexander (4), writing in 1925, quotes a report of Edgar T. Wherry to the effect that “under the microscope, between crossed nicols, the grains (of bentonite) show distinct double refraction.…. the grains being of visible dimensions in two dimensions,…. yet of colloidal dimensions in the third.” The isolation of Istanbul during the war period perhaps accounts for the fact that the M.I.T. work was overlooked. On account of this, the title and a number of sections in the original manuscript of this paper have been modified or omitted, because their inclusion after the appearance of Leaf’s publication would have been redundant. More particularly, sections on the use of polarized light, see Taylor (5), and on the construction of experimental apparatus have either been omitted entirely or reduced to a minimum. However, it seemed in place to leave a little of the theory upon which the method is based, and to emphasize the suitability of vanadium-pentoxide sols as a birefringent medium, particularly where photographic recording is desirable.
The Hardened and Tempered Microstructure of High-Speed Tool Steel as a Factor in Tool Performance
Authors: Wooding W. H.
Published: December 2022

The hardened and tempered metallurgical characteristics of a large number of tools representing various types of high-speed steels were studied to determine the probable cause for variation in tool life during conduct of continuous roughing-cut performance tests. The studies included the austenitic grain size, hardened and tempered microstructure, the Rockwell hardness of the finished tools, and the Shepherd hardened fracture grain size, as well as comparison of these properties with tool performance. The results of these studies indicated that, for various lots of a type of high-speed tool steel subjected to the same heat-treatment, variations do occur in tool performance, austenitic grain size, hardened and tempered microstructure, Rockwell hardness, and hardened fracture grain size. Of the variables observed, the hardened and tempered microstructure showed direct correlation with variation in tool performance. Within normal limits there appears to be no relationship between the hardened and tempered microstructure and the austenitic grain size, Rockwell hardness, or hardened fracture grain size. For lots of the same type of high-speed tool steel, subjected to the same heat-treatment, the characteristics of the hardened and tempered microstructure are directly associated with the speed of response, i.e., solution of carbide in the material at the austenitizing temperature. Red hardness being a function of the quantity of carbide dissolved during heat-treatment, the characteristics of the hardened and tempered microstructure are associated with red hardness and therefore are of considerable influence in the performance of tools.
X-Ray Diffraction as a Gage for Measuring Cold Work Produced in Milling
Authors: Zankl F. , Barkow A. G. , Schmidt A. O.
Published: December 2022

An x-ray diffraction analysis established the fact that the cold work produced in the workpiece was effected by the radial-rake angle of the milling cutter. A milling cutter with a negative radial-rake angle required more power than a cutter with a positive radial-rake angle. This study also revealed the fact that the negative radial-rake-angle cutter produced a more intense and deeper cold work in the workpiece, both in the case of two magnesium alloys and in S.A.E. 1020 steel.
Tracer-Point Sharpness as Affecting Roughness Measurements
Authors: Williamson D. E.
Published: December 2022

Tracer points are commonly made in conical form with a spherical tip for contacting the surface. Through measurement of surfaces with diamond points of various tip radius, it is shown that even relatively large radii may be used. The 0.0005-in-radius point commonly used in averaging instruments is wholly adequate for surfaces tested.
Master Charts for the Design of Vessels Under External Pressure
Authors: Windenburg D. F.
Published: December 2022

This paper presents the theoretical equations underlying nondimensional charts suitable for the design of circular cylindrical steel vessels under external pressure. The method used in constructing the charts is shown and their advantages and limitations are discussed. It is shown also how the charts can be used for the design of pressure vessels constructed of nonferrous and other materials which have nonlinear compressive stress-strain curves.
Computing Strength of Vessels Subjected to External Pressure
Authors: Sturm R. G. , O’Brien H. L.
Published: December 2022

This is a brief discussion of variables and considerations that must be treated when designing a pressure vessel for the collapsing load. A description is given of collapsing-pressure diagrams and the formula used in determining values. A method is presented which eliminates trial-and-error solutions by use of appropriate charts based upon instantaneous moduli of elasticity. Calculations and charts are shown for “A” nickel and stainless steel 17-7; (SA264, Type 301).
Investigation of Acid Attack on Boilers and the Effect of Repeated Acid Cleaning on the Metal
Authors: Farmer H. C.
Published: December 2022

The results of this investigation have served to clarify some of the controlling factors of acid attack which were not generally recognized. The investigation shows that stressed metal is more readily attacked by inhibited acid than stress-relieved metal. With a knowledge of the controlling factors, such as temperature, acid strength, and contact time, the operator can acid-clean boilers with a reasonable assurance that corrosion or metal attack will be reduced to a minimum.
Heavy-Duty Chain Drives for Marine Propulsion Service
Authors: Bremer N. C.
Published: December 2022

During the war, because of the shortage of helical-gear and electric drives for smaller Diesel-powered ships, transmission chain which had had a long record of successful applications in industry, was adopted for marine service. In 1942, after the Navy Department, Bureau of Ships, had conducted a series of tests on chain drive, it was fitted on 65-ft and 110-ft harbor tugs, and the Army Transportation Corps FP cargo vessels. This paper points out the advantages as well as the limitations of chain transmission applied to ship propulsion and mentions factors which contribute to efficiency, long life, quietness, and low maintenance costs.
The Horizontal Cyclone Burner
Authors: Grunert A. E. , Skog L. , Wilcoxson L. S.
Published: December 2022

In order to determine the practicability of burning crushed coal in the horizontal cyclone burner, tests were conducted some years ago on a 3-ft-diam model. Subsequently, a 5-ft-diam burner together with a secondary chamber and boiler were constructed and operated as a pilot plant, proving the feasibility of the burner and achieving many advantages in economy of construction and operation. As a result of successful pilot-plant operation, a developmental installation was made at the Calumet Station of the Commonwealth Edison Company of Chicago. This was an installation involving a steam-generating unit of 150,000 to 180,000 lb steam capacity per hr. The unit has been operating since September, 1944, during which time much experimental work has been done to improve the operating characteristics. The performance of this horizontal cyclone burner has definitely proved the principles involved to be sound, providing a simple, reliable, and efficient means of burning coals, particularly of the poorer grades having a high percentage of ash with low burning temperature.
Specific Studies Pertaining to Tool Wear, Chip Characteristics, and Surface Finish of Free-Cutting Steels
Authors: Witteman G. P.
Published: December 2022

Variables affecting cutting performances are estimated by several investigators to run into millions. These figures are raised to astronomical proportions and are therefore of no practicable value if we take into account variations in the analysis of the steel being cut, and the effect of the various phases in steelmaking, i.e., rolling, heat-treatment, cold-working, etc. Naturally, metallurgical control is essential if satisfactory machinability is to be attained. Specific cases are given, illustrating how increases in hardening elements will affect machinability. Studies of chip sizes and characteristics, supplemented by color photographs, give interesting information on machining properties and tool wear. Microhardness tests are used to study metallurgical differences and the effect of elements such as nitrogen and boron on the various constituents of the steel.
Effect of Microstructure on Machinability of Cast Irons—II
Authors: Field Michael , Stansbury E. E.
Published: December 2022

The general investigation of the effect of microstructure on the machinability of cast iron reported in Part I was continued on structures of varying pearlite and graphite size but with the addition of about five per cent of free steadite, the iron - iron phosphide eutectic. Finally, straight malleable iron and one type of pearlitic malleable iron were studied. The straight malleable iron had a structure consisting of ferrite and nodular graphite while the pearlitic malleable structure consisted of recombined carbon, ferrite, and nodular graphite. The tool life, power requirements, and surface finish were determined for these structures, and comparisons are shown with the structures of Part I. By means of these data the expected machinability of a cast iron can be determined by comparing its microstructure with those presented in this and the previous paper.
Instrumentation for Flight Testing of Thermal Anti-Icing Systems
Authors: Droege W. C.
Published: December 2022

At present there are only meager design data available to the aeronautical industry on the amount of heat necessary to keep an airfoil anti-iced in various icing conditions. Data obtained at the Aeronautical Ice Research Laboratory at Minneapolis from flight tests of thermal anti-icing systems of several U. S. Army Air Forces aircraft were limited by the instrumentation installed by the individual manufacturers. The specifications presented to guide the aeronautical industry in the instrumentation of such systems thus far have not been adequate. This has resulted in varied instrumentation of similar systems, giving a variety of results that were difficult to analyze and co-ordinate. It is desirable to draw upon the past experience of the Aeronautical Ice Research Laboratory to present what are felt to be the minimum instrumentation requirements for thermal anti-icing systems. The requirements presented herein should not be considered final, as additional instrumentation for more complex systems may be required in the future.
Abrupt Energy Transformation in Flowing Gases
Authors: Bailey N. P.
Published: December 2022

After setting up the basic equations of energy, flow, and acceleration, this paper compares theoretical and actual plane compression shocks in tubes. By making the single-plane-angle shock a special case of a plane shock, curves for solving numerical cases are presented. Even though most angle shocks encountered in engineering are three-dimensional, it is felt that the simple theory of single-plane shocks is helpful in understanding such phenomena without the complications of three-dimensional theory. Traverses of three-dimensional angle shocks in nozzle and orifice discharges are presented and discussed, and temperature traverses through shock diamonds in high-temperature streams are shown. Although no complete explanation exists for thermocouple readings in excess of the total gas temperature in such high-temperature shocks, their existence is established. As a last case of abrupt energy transformation in gas streams, tests of combustion with flow in a constant-area tube are given. Experiment and analysis agree that the assumptions of constant-area flow and steady or continuous flow do not appear to be simultaneously tenable when combustion is present.
Orifice Discharge Coefficients in the Viscous-Flow Range
Authors: Peterson G. S.
Published: December 2022

This paper covers the results obtained from calibrating two orifice assembly units for use in measuring lubricating-oil flow rates in aviation engines during flight. A brief summary of available published data on orifice coefficients in the viscous-flow range is included. In view of the limited amount of available published data of this type, it is suggested that the Fluid Meters Committee consider the need for publishing orifice-coefficient data in the viscous-flow range in the A.S.M.E. Fluid Meters Report.
A Simplified Method for the Design of Vibration-Isolating Suspensions
Authors: Lewis R. C. , Unholtz Karl
Published: December 2022

The paper presents a new type of chart treating of coupled natural frequencies of suspended bodies showing frequency ratios, nodal positions, and optimum selection of ratios directly in terms of physical dimensions of body to be mounted. Characteristics of newly designed family of isolator units are described.
Thermal Anti-Icing Survey on Mt. Washington
Authors: Guibert A. G.
Published: December 2022

Data on the performance of a few electrically heated cylinders of varying diameter and of an electrically heated airfoil in icing conditions are presented. The rate of catch of the supercooled drops (pounds of water per hour for 1-ft span) and the heat rate per unit area are given, together with a comment on the surface conditions, so that some indication of the severity of icing may be obtained. In general, it can be said that a heat requirement greater than that given in A.A.F. specifications for thermal antiicing seems indicated. The partial wettedness of the heated surfaces which was observed on the test equipment on Mt. Washington requires revision of the basic equations presented in a report by Tribus, Tessman, et al. (1). Computations of the ratio of the mass-transfer (evaporation) area to the heat-transfer area, on the basis of the revised equation similar to one suggested by Tribus were made for a number of runs and the results are presented in tabular form. The effects of various surface treatments with respect to surface wettedness and with respect to the heat-transfer data are discussed briefly.
Development and Testing of a Gas-Turbine Combustor
Authors: Hershey A. E.
Published: December 2022

This paper treats of the development work on a combustor for a 2200-hp gas turbine, and its subsequent performance under tests. The design involved a simple and compact unit operating on the open cycle without regenerator, reheater, or intercooler. Because of the necessity of using No. 6 or bunker C fuel, with inherent burning difficulties under the limitations imposed by the specifications, many problems had to be overcome before an efficient combustor could be assured.
Centrifugal Governor in Elevator Service
Authors: Hymans F.
Published: December 2022

This paper is concerned with the performance of the governor during the period of free fall of the car upon a failure of the hoisting ropes. In two examples, one in connection with a medium-speed and the other with a slow-speed elevator, the performance of the governor is determined together with the inertia forces necessary for a rational design. For purposes of comparison, the same governor is used in both examples, adapted to the different car speeds by suitable gearing to the driving sheave.
Torsional Stress Analysis of Twist-Drill Sections by Membrane Analogy
Authors: Neubauer E. T. P. , Boston O. W.
Published: December 2022

The purpose of the experiment was to find the nature of the stress distribution in different drill cross sections due to an applied torque. This paper describes the procedure used and the results obtained.
Internal-Shoe Clutches and Brakes
Authors: Von Mehren O.
Published: December 2022

Too often the design of internal-shoe clutches is treated inadequately, in some cases even, dependence being placed upon empirical formulas which fail to provide complete utilization of the potential capacities of this type of unit. The author discusses these shortcomings of current practice and presents the problems in connection with this type of clutch or brake which require classification. An exact method with relative formulas is provided for the necessary design calculations. The text is supplemented by appendixes in which the derivation of the formulas is given, as well as a mathematical analysis of the entire design problem.
Heat Transfer to Molten Metals
Authors: Martinelli R. C.
Published: December 2022

The contents of the paper are based on an extension of the analogy between heat and momentum transfer. Following the suggestion of von Kármán (9), the turbulent-flow field is divided into a laminar sublayer, a buffer layer, and a turbulent core. The thermal resistances of the laminar sublayer and the buffer layer are calculated as in the paper by Boelter, Martinelli, and Jonassen (1), but the thermal resistance of the turbulent core is re-evaluated for very low values of the Prandtl modulus (molten metals) by considering the simultaneous transfer of heat by molecular conduction and eddy diffusion. The relative importance of the thermal resistances of the laminar sublayer, buffer layer, and turbulent core is discussed and the temperature distribution in the fluid is evaluated for various magnitudes of the Prandtl modulus. It is demonstrated that the unit conductance for convective heat transfer is proportional to the square root, rather than the first power, of the friction factor. A tentative analysis is made of the data of Cope (19) for heat transfer in rough pipes.
Heat Transfer by Free Convection From Heated Vertical Surfaces to Liquids
Authors: Touloukian Y. S. , Hawkins G. A. , Jakob M.
Published: December 2022

The present investigation deals with the study of heat transfer by natural convection from vertical cylindrical surfaces to water and ethylene glycol. The results are correlated within the laminar range for (NGr·NPr) from 2(108) to 4(1010) according to the expression NNu=0.726(NGr⋅NPr)1/4 and within the turbulent range for (NGr·NPr) from 4(1010) to 9(1011) the correlation is best represented by the expression NNu=0.0674 [NGr(NPr)1.29]1/3 The foregoing correlations represent the experimental data with a mean deviation of 5.6 per cent and 3.5 per cent for the laminar and turbulent ranges, respectively. The ranges of some of the important variables involved in the tests are given in Table 1 of the text.
Recent Developments Concerning the Properties of Cast Steels
Authors: Briggs C. W.
Published: December 2022

The properties of a number of low-alloy cast steels have been determined from production heats, hence the values obtained represent the values normally expected in the manufacture of steel castings. The cast low-alloy steels, in general, have slightly higher hardenability and strength and slightly lower ductility than wrought steels of similar composition, on heat-treatment. In this paper property ranges for strength and ductility are given for cast steels receiving different heat-treatments. The depth of section to which cast steel will harden can be estimated by the employment of the end-quench hardenability test. This test was used to study a number of carbon and alloy cast steels. It was found that the hardenability values of cast steels are similar to those of wrought steels of comparable analyses and grain sizes. Hardenability curves for typical carbon cast steels are given and hardenability bands for a number of low-alloy cast steels are illustrated. All degrees of hardenability, shallow- to deep-hardening, may be attained by the proper selection of cast steels. Studies on notched-bar impact specimens of cast steel revealed that by varying the structure of a single cast steel by heat-treatment, it is possible to change the low-temperature notched-bar impact values of the steel. Based upon the results of the investigation, it is concluded that no one alloy cast steel produces the best impact resistance, for all types of heat-treatments, at all testing temperatures. Alloy cast steels demonstrate excellent notched-bar impact properties at low-temperatures, which make them ideal for low-temperature-service applications.
Temporary Installation of Shasta Turbines at Grand Coulee
Authors: Sloane H. H.
Published: December 2022

Two hydraulic turbines of 103,000 hp at rated head of 330 ft, designed for the Shasta power plant were transferred to Grand Coulee early in 1942, to supply power for war industries. The engineering problems encountered in installing the units in the completed Coulee turbine pits and methods of solving them were unique. The installation, as measured by the efficient performance of the units and large amount of power made available at a critical time, proved a very valuable asset to the war effort.
Progress Report No. 1 on Tool-Chip Interface Temperatures
Authors: Trigger K. J.
Published: December 2022

The author presents some of the results of a series of tests in which the principal phase of study concerned the temperature developed at the contacting surface of the tool and the chip. This tool-chip interface temperature is referred to as the “cutting” temperature. The determination of the tool-chip interface temperature was by means of the Herbert-Gottwein tool-work thermocouple wherein the steel workpiece constituted one member of a thermo-couple and the cemented-carbide insert the other member. This principle has been used in the study of cutting temperatures, the investigation of friction between unlike metals, the study of surface temperatures of brass wire drawn through steel dies and for investigation of surface temperatures of mating gears of unlike metals.
Economies in Power-Plant Design
Authors: Krieg Edwin Holmes
Published: December 2022

The primary objective of power-plant design is to secure the highest over-all return on the investment in the plant. This means that the design attempts to attain the best combination or balance between: (a) lowest fixed charges through low first cost and high availability, and (b) lowest operating charges through low fuel, labor, and maintenance costs. True, this is not the whole story, for it presumes adequate system planning which analyzes the “need” for the station. In other words, when is the plant needed; where is the plant needed; and how large a plant is needed? An outline of these elements is covered by long strokes with a wide brush in the Appendix, as plant design is the main point of discussion. Furthermore, the cost of fuel, the lifetime load factor of the plant, and other considerations such as cost cycles (1) influence the selection of the plant heat cycle and equipment (2). This paper outlines a few examples of economies in the design of public-utility power plants mostly along the lines of first cost and availability.
Rubber Springs—Shear Loading—II
Authors: Downie Smith J. F.
Published: December 2022

In a previous paper the author developed theoretical stress-strain relationships for rubber of various shapes loaded in shear. In this paper the author presents additional theory and data.
Oil Flow and Temperature Relations in Lightly Loaded Journal Bearings
Authors: Boyd John , Robertson B. P.
Published: December 2022

The trend toward higher speeds for certain types of apparatus and the decrease in weight of the moving parts which usually accompanies such a change has resulted in the application of an increasingly large number of bearings which operate at relatively high speeds and comparatively light loads. Many of these applications use sleeve-type bearings which are supplied with force-feed lubrication. In order to obtain data which may be used in designing bearings for such use, the oil flows and running temperatures of two common types of sleeve bearings have been investigated and the results compared with theoretical predictions.
Axial-Flow Compressors for Gas Turbines
Authors: Ponomareff A. I.
Published: December 2022

The development of the gas turbine during the last decade has opened a new field for compressor application. The compressor is an essential component of every gas-turbine power plant. It delivers air at some elevated pressure to the burner in sufficient quantity to maintain an efficient combustion of fuel and to cool the products of combustion to some acceptable temperature at the turbine inlet. The axial-flow compressor is particularly adaptable to gas-turbine applications for aviation, marine, or land service. This paper deals with the operating principles, characteristics, types, and other data pertaining to the axial-flow compressor.
Determination of Gas-Turbine Combustion-Chamber Efficiency by Chemical Means
Authors: Lloyd Peter
Published: December 2022

Because of certain limitations of the heat-balance method of determining combustion-chamber efficiency, a more accurate chemical method of analysis has been developed utilizing the gravimetric technique. This method has the added merit of indicating the nature of combustion loss, which at times may be very useful. Various approximate methods, chemical, physicochemical, and physical can be devised, all of which require calibration against an exact and complete chemical determination. Details of the method and its application to the gas-turbine problem are presented.
Mechanisms of Combustion and Their Relation to Oil-Burner Design
Authors: Heiple H. R. , Sullivan W. A.
Published: December 2022

The combustion of fuel oils is a very complex process from the viewpoint of the kineticist. In any attempt to treat this subject theoretically the over-all process must be broken down into a group of consecutively and frequently concurrently occurring chemical and physical changes and each of these analyzed in turn. From an integration of the conclusions obtained by this means a more comprehensive conception of the factors involved in the burning of hydrocarbon fuel oils may be attained. In this paper an attempt will be made to show what processes are involved, and means by which this information may be utilized in the design of burners will be indicated.
Radio-Frequency Heating in the Woodworking Industry
Authors: Macaluso F. L.
Published: December 2022

Radio-frequency heating is finding wide application in the woodworking industry for such processes as edge-gluing, plywood manufacture, drying, assembly-gluing. The theory of radio-frequency heating is reviewed briefly, and how this type of heat is applied in various applications is described. Several case histories of actual manufacturing problems are taken up. The recent Federal Communications Commission Regulations on the use of radio-frequency power for industrial heating are treated comprehensively.
Studies in Boundary Lubrication—II: Influence of Adsorbed Moisture Films on Coefficient of Static Friction Between Lubricated Surfaces
Authors: Campbell W. E. , Thurber E. A.
Published: December 2022

Extraordinarily high values of the coefficient of static friction between steel surfaces lubricated with straight chain normal hydrocarbons (heptane to decane) are shown to be due to a film of adsorbed moisture at the solid-liquid interface. Friction measurements on a highly refined paraffin-base oil applied to surfaces in equilibrium with a dry and a moist atmosphere, confirm this idea, the coefficient of friction being 0.35 for the dry and 0.6 for the moist lubricated surfaces. Friction measurements are recorded for four fundamentally different lubricant types on steel, brass, and glass in equilibrium with dry air and air of 75 per cent humidity, respectively. The friction is in all cases raised from 40 to 70 per cent in the high humidity, the effects being particularly pronounced on glass. The results of the tests provide an explanation for many of the discrepancies among oiliness results in the literature obtained by the static-friction method, and indicate that the humidity of the atmosphere plays a significant part in the mechanism of boundary lubrication.
The Hydrodynamics Laboratory of the California Institute of Technology
Authors: Knapp R. T. , Levy Joseph , O’Neill J. P. , Brown F. B.
Published: December 2022

This paper presents a description of the Hydrodynamics Laboratory and its principal pieces of equipment that have been developed during the last five years. The field of investigations to be undertaken by the Laboratory is presented in general terms.
Curvature-Acceleration Relations for Plane Cams
Authors: Baxter M. L.
Published: December 2022

This paper discusses cam curvature as an important limitation in cam design, and presents formulas not previously published for obtaining this curvature. Flat and circular followers are considered for both translational and rotational follower motion. Constructions for obtaining the center of curvature by graphical means are also given. The formulas are listed early in the paper in convenient tabular form for reference purposes, followed by detailed discussion and derivations.
Studies in Boundary Lubrication—III: The Wear of Carbon Brushes in Dry Atmospheres
Authors: Campbell W. E. , Kozak Rose
Published: December 2022

The dusting wear of carbon brushes is studied in dry nitrogen at atmospheric pressure. The effect of water, oxygen, and carbon dioxide on dusting wear is described, and the results compared with those of investigations carried out under partial vacuum conditions. No effect of current, up to 114 amp per sq in. is found under the conditions studied. It is shown that a highly oriented natural graphite specimen or an oriented graphite brush, operated so that the faces of the cleavage planes rub on a plane rotating copper surface, neither dusts nor produces wear on the copper surface in dry nitrogen. When operated so that the edges of the cleavage planes rub against the plate, rapid dusting wear takes place and the copper surface is deeply scored. The dusting rate of carbon brushes in dry nitrogen against several metals is given. The rate is shown to decrease as the hardness of the metal increases, the behavior of brass being exceptional. It is found to be zero on smooth chromium and rhodium surfaces. On the assumption that an adsorbed lubricant film prevents scoring of the plate by the edges of the graphite crystals, allowing them to be oriented, the results are shown to be consistent with recent theories of solid friction.
Streamlining Effect on Air Resistance and Smoke Lifting on Steam Locomotives
Authors: Griffin J. F.
Published: December 2022

A test was conducted in 1946 in the wind tunnel at the Daniel Guggenheim School of Aeronautics at New York University with a 1/12-scale model of an existing modern 4-8-4 type locomotive. To this model was added for various runs different features of streamlining or smoke-lifting deflecting plates or both. Each change constituted, in effect, a different model. This paper covers a report on the five models which proved to be of the most importance.
An Investigation of the Variation in Heat Absorption in a Pulverized-Coal-Fired Water-Cooled Steam-Boiler Furnace: I—Variations in Heat Absorption as Shown by Measurement of Surface Temperature of Exposed Side of Furnace Tubes
Authors: Schueler L. B.
Published: December 2022

This report is one of several current formal reports (1) covering the activities of the ASME Special Research Committee on Furnace Performance Factors. These investigations were undertaken early in 1945, as one of the direct contributions of the Committee to the fundamental knowledge of heat-transfer processes in water-cooled boiler furnaces. The present investigation is still under way and this report is an introduction to and description of the project along with a presentation of significant data procured and analyzed up to December, 1946. The investigation is being carried out on boiler No. 11 at the Tidd Plant of The Ohio Power Company, Brilliant, Ohio. Directly co-operating with the Committee in the installation of apparatus, testing, and analysis of data are the American Gas and Electric Service Corporation, Combustion Engineering Company, and U. S. Bureau of Mines, Pittsburgh Experiment Station. It was at the initial suggestion and invitation of Mr. Philip Sporn, a member of the main Committee, that a comprehensive investigation of furnace-heat absorption on a full-scale unit was held desirable, and one of the Tidd Plant boilers was made available to the Committee for such an undertaking.
An Investigation of the Variation in Heat Absorption in a Pulverized-Coal-Fired Water-Cooled Steam-Boiler Furnace: II—Furnace Heat Absorption Efficiency as Shown by the Temperature, Composition, and Flow of Gases Leaving the Furnace
Authors: Reid W. T. , Cohen Paul , Corey R. C.
Published: December 2022

As part of an investigation of the factors affecting the performance of furnaces, the heat-absorption efficiency of the furnace of a pulverized-coal-fired dry-bottom steam boiler was determined from the sensible heat in the gases at the furnace outlet. The sensible heat was determined from the temperature of the gases, which was measured by traversing the furnace outlet with a high-velocity thermocouple, and from the quantity of gas leaving the furnace, which was computed from the composition of the gas and the rate of fuel firing. Data are given for the distribution at the furnace outlet of excess air, gas temperature, and mass flow. The effect on furnace heat-absorption efficiency is shown for variations in (a) the heat available in the furnace, (b) the excess air, (c) the angle of inclination of the burners, and (d) the condition of the furnace with respect to deposits of ash and slag on the heat-absorbing surfaces. The data of this investigation were correlated by a modified form of the Hudson-Orrok equation, which relates empirically the furnace heat-absorption efficiency to the weight of wet gases at the furnace outlet, per unit heat available in the furnace, and the heat available in the furnace per square foot of projected radiant heating surface.
An Investigation of the Variation in Heat Absorption in a Pulverized-Coal-Fired Water-Cooled Steam-Boiler Furnace: IV—Comparison and Correlation of the Results of Furnace Heat-Absorption Investigations
Authors: Mumford A. R. , Bice G. W.
Published: December 2022

In this part of the symposium the three preceding sections of the report are compared, and satisfactory coordination is accomplished for the first two sections. The tube-surface temperature measurements show furnace heat absorptions which can be co-ordinated with the absorptions indicated by the surveys of the gas conditions at the furnace outlet by applying a correction to the gas-temperature measurement, or by varying the tube-to-water film conductance. A method of evaluating furnace cleanliness is developed and applied. A suggested basis of comparing furnaces is discussed.
VI—Dielectric-Constant and Refractivity Data
Authors: Miller J. G.
Published: December 2022

The dielectric constant and refractivity data already established at lower pressures for the twelve gases under consideration need little improvement. A few outstanding gaps in these data are specified. Accurate high-pressure data have been published for only a few of the gases, principally hydrogen, nitrogen, carbon dioxide, and ammonia. Even with these four gases, improvement in the techniques of measuring dielectric constants at high pressures is needed so that more accurate and more extensive studies can be made.
Generalized Thermodynamics of High-Temperature Combustion
Authors: Hottel H. C. , Williams G. C. , Satterfield C. N.
Published: December 2022

The ability to calculate the performance of any proposed type of heating operation or power-plant combustion cycle requires a knowledge of the thermodynamic properties of the system. If the systems encountered consist of any combination of the four species, carbon-hydrogen-oxygen-nitrogen, in any reasonable proportion, the number of thermodynamic charts necessary for a solution with minimum interpolation would be enormous without specially developed procedures. This paper presents a method of expressing the thermodynamic properties of the four-component system in a dimensionless form which permits putting the whole system onto a simple set of charts for easy engineering use. The present data have particular value in calculating flame temperatures and in solving the performance of liquid-fuel rocket power plants. The data span the range of operation of conventional combustion systems and therefore also apply to systems such as furnaces operated with oxygen enrichment or very high preheat, as well as most usual power cycles. The method of use is illustrated by application to a rocket system.
Temperature-Reduction Problems in Sugar-Beet Storage
Authors: Barmington R. D.
Published: December 2022

Successful storage of sugar beets is dependent upon low storage temperatures. In parts of the United States where night temperatures are near the freezing point during the storage period, artificial ventilation during the night has been suggested as a means of removing heat from the beets. While this method has possibilities there has been a lack of knowledge and understanding regarding the large quantity of air required, and consequently the large blowers and ducts necessary. While the size of the structures would not be impractical, it is necessary to understand the magnitude of the problem before an attempt is made to design a commercial-size storage.
Analysis of Tests on Positive-Displacement Meters for Liquid Hydrocarbons
Authors: Ambrosius E. E.
Published: December 2022

This paper gives an amplification of results of tests on one meter and represents a method of analysis of data from the tests conducted by the ASME Special Research Committee on Fluid Meters and the API Topical Committee on Volumeter Research, to determine the characteristics of displacement-type mechanical meters when measuring liquid hydrocarbons. It is a continuation of an earlier paper, and presents data with a method of further analysis beyond that made in the preliminary study. The early paper discussed the results in a general way. A more thorough study of the data on a particular meter, such as herein presented, can point the way toward close control of meter-performance characteristics for any particular design.
Developments in Kraft-Process Recovery-Unit Design and Performance
Authors: Allen R. K.
Published: December 2022

Recent developments in design of Kraft-process recovery units, utilizing the Tomlinson method of combustion, are described. The comparative performance is given of early and recent types of Tomlinson recovery units. Economic factors affecting the selection of recovery-system equipment are included.
Silicone Rubber—New Properties for Design Engineers
Authors: Irby G. S. , Goss Wyman , Pyle J. J.
Published: December 2022

Silicone rubber is a new synthetic elastomer which exhibits exceptional properties of thermal stability. The physical, chemical, and electrical properties of this material, as affected by high and low temperatures, have been studied. The results of this study, together with fabrication techniques and proven applications, are compared to show where silicone rubber may be of best use to the design engineer.
A Framework for Estimating Effects of Combustor Turbulence on Turbine Profile Loss Generation
Authors: Gakhar Kanika , Folk Masha , Greitzer Edward M. , Tan Choon S.
Published: December 2022

This paper describes a framework to quantify the effect of freestream turbulence, generated by mixing processes in a combustor, on turbulent boundary layer loss generation in the high-pressure turbine downstream of the combustor. The regime of freestream turbulence common to gas turbine aero engines is identified and it is shown that the dissipation loss coefficient in this regime can be determined using existing measurements of the effect of freestream turbulence on skin friction. The paper shows that combustor-generated freestream turbulence can increase the profile loss coefficient of a typical high-pressure turbine blade by as much as 28%. A relation has been derived between a non-dimensional turbulence parameter, which characterizes the freestream turbulence, and the increase in turbine boundary layer dissipation, which quantifies the decrease in turbine efficiency. The relation provides guidelines for combustor turbulence modifications that lead to turbine performance benefits. The framework has been applied in example trade studies which show that increasing the size of dilution ports and increasing the length of the combustor can decrease high-pressure turbine profile loss generation to potentially increase stage efficiency up to 0.5%.
Incipient Immobilization Detection for Lightweight Rovers Operating in Deformable Terrain
Authors: Lines Austin P. , Elliott Joshua J. , Ray Laura E.
Published: December 2022

This article presents a new method of detecting incipient immobilization for a wheeled mobile robot operating in deformable terrain with high spatial variability. This approach uses proprioceptive sensor data from a four-wheeled, rigid chassis rover operating in poorly bonded, compressible snow to develop canonic, dynamical system models of robot’s operation. These serve as hypotheses in a multiple model estimation algorithm used to predict the robot’s mobility in real time. This prediction method eliminates the need for choosing an empirical wheel–terrain interaction model, determining terramechanics parameter values, or for collecting large training datasets needed for machine learning classification. When tested on field data, this new method warns of decreased mobility an average of 1.8 m and 2.9 s before the rover is completely immobilized. This system also proves to be a reliable predictor of immobilization when evaluated in simulated scenarios of rovers with passive suspension maneuvering in more variable terrain.
UiS Subsea-Freight Glider: A Large Buoyancy-Driven Autonomous Cargo Glider
Authors: Ahmad Usman Nawaz , Xing Yihan , Ma Yucong
Published: December 2022

This study presents the baseline design for the autonomous subsea vehicle capable of traveling at a lower speed of 1 m/s with an operating range of 400 km. Owing to UiS subsea-freight glider’s (USFG) exceedingly economical and unique propulsion system, it can transport various types of cargo over variable distances. The primary use-case scenario for the USFG is to serve as an autonomous transport vessel to carry CO2 from land-based facilities to subsea injection sites. This allows the USFG to serve as a substitute for weather-dependent cargo tankers and underwater pipelines. The length of the USFG is 50.25 m along with a beam of 5.50 m, which allows the vessel to carry 518 m3 of CO2 while serving the storage needs of the carbon capture and storage (CCS) ventures on the Norwegian continental shelf. The USFG is powered by battery cells, and it only consumes a little less than 8 kW of electrical power. Along with the mechanical design of the USFG, the control design is also presented in the final part of the paper. The maneuvering model of the USFG is presented along with two operational case studies. For this purpose, a linear quadratic regulator (LQR)- and proportional-integral-derivative (PID)-based control system is designed, and a detailed comparison study is also shown in terms of tuning and response characteristics for both controllers.
Acoustic modes of a spherical thin-walled tank for liquid propellant mass gauging: Theory and experiment
Authors: Muratov Cyrill B. , Rogers Joseph , Khasin Michael
Published: December 2022

Acoustic response of a thin-walled spherical flight tank filled with water is explored theoretically and experimentally as a testbed for an application of Weyl's law to the problem of mass-gauging propellants in zero-gravity in space. Weyl's law relates the mode counting function of a resonator to its volume and can be used to infer the volume of liquid in a tank from the tank's acoustic response. One of the challenges of applying Weyl's law to real tanks is to account for the boundary conditions which are neither Neumann nor Dirichlet. We show that the liquid modes in a thin-walled spherical tank correspond to the spectrum of a slightly larger spherical tank with infinitely compliant wall (Dirichlet boundary condition), where Weyl's law can be applied directly. The mass of the liquid enclosed by this “effective” tank's wall is found to equal the actual mass of the liquid plus the mass of the wall. This finding is generalized to thin-walled tanks and liquid configurations of arbitrary shapes and thus provides a calculable correction factor for the propellant mass inferred using Weyl's law with Dirichlet boundary conditions.
Circulation of Ngari Virus in Livestock, Kenya
Authors: Omoga Dorcus C. A. , Tchouassi David P. , Venter Marietjie , Ogola Edwin O. , Eibner Georg Joachim , Kopp Anne , Slothouwer Inga , Torto Baldwyn , Junglen Sandra , Sang Rosemary
Published: December 2022

Surveillance of vectors and hosts for infection with zoonotic arthropod-borne viruses is important for early detection and intervention measures to prevent outbreaks. Here, we report the undetected circulation of Ngari virus (NRIV) in apparently healthy cattle, sheep, and goats in Kenya.