bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mass Flowmeter for In-Flight Refueling
Authors: Taylor C. F. 
Published: February 2022

Abstract
A new mass flowmeter for in-flight refueling of jet aircraft is described. This flowmeter incorporates very large capacity in a compact rugged unit of unusually high accuracy. Other features are light weight, low pressure drop, no rotating fluid seals, and fast response to sudden changes in fuel flow rate. This has been achieved by applying the angular momentum principle to obtain a mechanical torque that is linearly proportional to mass rate of flow.
Pressure Drop and Flow Characteristics of Short Capillary Tubes at Low Reynolds Numbers
Authors: Kreith Frank , Eisenstadt Raymond 
Published: February 2022

Abstract
The pressure drop and flow characteristics of short capillary tubes have been investigated experimentally for length-to-diameter ratios varying from 0.45 to 18 at diameter Reynolds numbers ranging from 8 to 1500. In the range of the dimensionless modulus (Lμ)/(VD2ρ) from 4 × 10−3 to 3 to 10−1, the experimental data agree within 15 per cent with a mathematical theory by Langhaar (1). At a value of (Lμ)/(VD2ρ) of about 0.3 the experimental data approach the Poiseuille laminar-flow theory (2). For very short tubes (L/D &lt; 0.5) the experimental results deviate from Langhaar’s theory at values of Lμ/VD2ρ less than 4 × 10−3, and at Lμ/VD2ρ equal to 5 × 10−4, the pressure drop is twice as large as that predicted by Langhaar’s theory (1). The experimental results for tubes having very short aspect ratios are in agreement with data obtained by Zucrow (12) with short square-edged jets. It was found that the flow rate Q˙ through a short capillary tube can be related empirically to the over-all pressure drop Δp¯ raised to a power N. The exponent N is a function of the length-to-diameter ratio L/D varying from 0.5 at L/D equal to 0.45 to 0.91 at L/D of 18. The trend of the curve suggests an asymptotic approach to unity, the exponent for Poiseuille-type flow. The results of this study have application to: (a) Simulating flow through screens, doors, cracks, and fissures in small-scale model testing of buildings in atmospheric wind tunnels. (b) Automatic control devices where capillary tubes are used as hydraulic resistances in a larger line and in nozzle-flapper combinations. (c) Heat pumps and air-conditioning equipment where short capillary tubes are used as two-way control valves. (d) Flow through compact heat exchangers and porous materials.
An Analytic Procedure for Optimizing the Selection of Power-Plant Components
Authors: Wilson W. A. 
Published: February 2022

Abstract
It is the purpose of this paper to inquire into systematic procedures for optimizing the selection of equipment comprising a steam power plant. The inquiry is not motivated by any conviction that plants as designed depart significantly from optima, but rather stems from the belief that the labor of the inevitable cut and try process of final component selection can be reduced. It appears to be possible by analytical techniques to narrow the range in which detailed explorations are required.
Applications of an Enthalpy-Fuel/Air Ratio Diagram to “First Law” Combustion Problems
Authors: Powell H. N. 
Published: February 2022

Abstract
An “absolute enthalpy” is defined which has the advantage that the enthalpies of different systems are similar and compatible quantities regardless of differences in state or chemical composition. An enthalpy-fuel/air ratio diagram for equilibrium state combustion gases is formulated using absolute enthalpies. On this diagram, virtually all processes which involve combustion and combustion product gases—and which are entirely within the scope of the first law of thermodynamics—can be represented by straight lines. Such a diagram therefore provides a very rapid and flexible method of solving many frequently occurring combustion problems. Procedures for handling the following typical problems are developed: Determination of adiabatic flame temperatures, theoretical heat releases, combustion efficiencies (from experimental temperature measurements), and the adiabatic mixing of two streams. Absolute enthalpy and heat-capacity data for (CH2)y-air (in 100 R increments) and (CH3)y-air (in 50 K increments) systems are tabulated for lean and rich composition ranges. Above ~ 3000 R ~ 1400 K the enthalpy and heat-capacity functions are pressure sensitive and the tabulated data are for 1 atm.
The Influence of Lead on Metal-Cutting Forces and Temperatures
Authors: Shaw M. C. , Smith P. A. , Loewen E. G. , Cook N. H. 
Published: February 2022

Abstract
The effects of additions of lead and sulphur to steel upon tool-face friction F, cutting energy per unit volume u, and tool-face temperature θ¯t were investigated. By means of high-speed flash pictures of chips in the process of being formed, it was found that lead was effective in decreasing chip thickness at all speeds, but particularly at high speeds. Sulphur, on the other hand, was found most effective in this regard at tool temperatures (speeds) below about 900 F. It was found that certain cutting fluids (principally cutting oils) interfered with the action of lead and sulphur, and fluids that are normally effective on ordinary steels may give poorer results than air upon steels containing lead or sulphur. In all cases leaded steels were found to give lower values of F, u, and θ¯t than comparable nonleaded steels and the improvement due to lead was far greater than could be achieved from cutting fluids at speeds of 150 fpm and above. The paper ends with a note of warning that the results on F, u, and θ¯t cannot be used to predict tool life directly and an example is presented which illustrates this point.
Force Relationships in the Machining of Low-Carbon Steels of Different Sulphur Contents
Authors: Boulger F. W. , Hartner H. E. , Lankford W. T. , Garvey T. M. 
Published: February 2022

Abstract
The force relationships obtained in the machining of a series of low-carbon open-hearth steels containing various amounts of sulphur from 0.025 to 0.250 per cent were investigated in a constant-pressure lathe and in a conventional lathe. A wire-resistance, strain-gage dynamometer was used to measure the forces acting on a high-speed tool for various cutting conditions. In the constant-pressure test, sulphur additions increased the feed obtained with a given thrust load. The addition of sulphur reduced the forces acting on the tool for equivalent feeds in both test lathes. Theoretical calculations disclosed that the effectiveness of increased sulphur contents results from decreased friction between the chip and the tool and from an accompanying reduction in strain during chip formation. The decrease in friction and strain reduced the work required for removal of a unit volume of metal during machining. Shear stress was not a direct function of sulphur content, but generally decreased with feed. Results of conventional lathe tests generally corroborated those obtained in the constant-pressure lathe.
Leaded Steel and the Real Area of Contact in Metal Cutting
Authors: Shaw M. C. , Smith P. A. , Cook N. H. , Loewen E. G. 
Published: February 2022

Abstract
The action of lead in free-machining steel is discussed and the thickness of the layer of lead responsible for the improved lubrication between chip and tool is found to be extremely thin. Measurements made on the same steel with and without lead present enable the real area of contact between chip and tool to be estimated and this is found to be between 1 and 2 per cent of the apparent area of contact. The cutting characteristics of steel containing lead are compared with those for steel without lead as well as those for pure lead. It is found that the presence of lead makes effective fluids such as carbon tetrachloride less sensitive to an increase in cutting speed.
Cutting-Fluid Evaluation
Authors: Husa H. W. 
Published: February 2022

Abstract
Transfer of radioactive material from a cutting tool to the chips produced in facing the end of a steel tube is used as a means of measuring tool-wear rate. The lathe is operated at commercial feeds and speeds. This technique permits accurate tool-wear evaluation with very short machining time and a consequent small consumption of stock. Protection of personnel against radiation requires simple precautions. Evaluation of a cutting oil may require consideration of the roughness of the cut surface or the cutting temperature in addition to the tool-wear rate. The properties of the material cut influence the type of tool wear experienced and may affect the choice of variables which must be considered in addition to tool-wear rate. Results for typical compound and mineral oils in the machining of both 1015 and 1045 steels are reported.
An Effort to Use a Laboratory Test as an Index of Combustion Performance
Authors: Ceely F. J. , Wheater R. I. 
Published: February 2022

Abstract
This paper discusses results of a study in progress to determine if the CRL reactivity test can be applied as an index of combustion performance in pulverized fuel-fired steam generators. Before undertaking an extensive program of correlating laboratory data against actual combustion experience, it was necessary to conduct the study on a limited basis to establish whether or not the results would justify an extensive effort. The authors present some significant data accumulated during this study phase and conclude that further investigation is warranted on a larger scale.
Determination of Thermal Conductivities of Metals by Measuring Transient Temperatures in Semi-Infinite Solids
Authors: Hsu S. T. 
Published: February 2022

Abstract
The temperature on the flat side of a semi-infinite solid is suddenly raised to a certain value. Then at two stations inside the solid, the temperature variations with time are recorded by means of thermocouples, a string galvanometer, and synchronized photographic equipment. Both the thermal conductivity and specific heat can be determined in the same experiment. The time for measurement is only 30 sec. The result is estimated to be accurate to within 2 per cent for certain metals.
Properties of Misaligned Journal Bearings
Authors: DuBois G. B. , Ocvirk F. W. , Wehe R. L. 
Published: February 2022

Abstract
Properties of misaligned journal bearings under hydrodynamic conditions of lubrication are presented as observed from experimental data. Curves in dimensionless form give journal-bearing attitude as a function of the usual bearing variables and the couples which produce misalignment. Examples are given showing the application of the dimensionless curves to typical problems of misaligned bearings.
The Fluid Dynamic Theory of Gas-Lubricated Bearings
Authors: Ausman J. S. 
Published: February 2022

Abstract
A differential equation for the pressure distribution in gas-lubricated slider bearings is derived from the basic equations of fluid mechanics. The equation is an extension of Harrison’s gas-bearing equation in that the infinite width and isothermal restrictions have been removed. A perturbation solution is proposed and is carried out for the special case of an infinitely wide, self-lubricating journal bearing. Comparisons with numerical solutions to Harrison’s equation indicate that the first three terms in the series solution are sufficient to determine the pressure distribution and bearing load with reasonable accuracy.
On the Theory of Grease-Lubricated Thrust Bearings
Authors: Slibar A. , Paslay P. R. 
Published: February 2022

Abstract
Experimental results have shown that grease can be considered to be a Bingham material. By introducing the yield criteria due to Hencky-von Mises-Huber, the stress-deformation rate relations for the lubricating material are derived. Making use of the characteristic parameters of a rotating thrust bearing, a perturbation procedure is used to obtain a solution governing the steady state. When the critical shear stress of the grease equals zero, this solution becomes the viscous one. Curves are given for design purposes which can be used by the lubrication engineer directly to obtain the prediction of the properties of a thrust bearing.
Cavitation Characteristics of Gate Valves and Globe Valves Used as Flow Regulators Under Heads Up to About 125 Feet
Authors: Ball J. W. 
Published: February 2022

Abstract
The series of tests discussed in this paper was made for the purpose of determining whether or not gate valves or globe valves could be used satisfactorily for regulating releases from irrigation-distribution systems under heads up to about 125 ft. Both types of valves proved unsuitable for making free-flow releases because of the wide dispersion of the jets under throttled conditions. Confinement of the jets to pipelines downstream induced cavitation in and downstream of the valves and a study was made of the pressures in the pipelines upstream and downstream of 6, 8, 10, and 12-in. gate valves, and a 6-in. globe valve to evolve a means of eliminating or minimizing the cavitation. A pressure relationship or “cavitation index” was found to be a useful means of determining the limits of differential head and back pressure to either control the location of, minimize, or eliminate cavitation damage. The design of the water passage immediately downstream from the valves and the pressure within this passage were the two main factors influencing the cavitation characteristics of an installation. One of the most effective means of eliminating cavitation damage below gate valves was the placing of sudden enlargements in the pipe sections immediately downstream. No damage could be detected in the concrete lining of the sudden enlargement under heads up to 150 ft with back pressures of approximately 15 ft, although noise similar to that which accompanies cavitation was present at heads in excess of about 90 ft.
A limited number of tests were made to study the resistance of rubber-like products to cavitation-erosion and their use in protecting the downstream pipe wall against this erosion. The conclusion was reached that such protection should not be used except in cases where cavitation will be mild.
Some consideration was given to venting the area in the top of the pipe just downstream of the valve, but this was considered objectionable because of the influence of entrained air on flow conditions and measuring devices, particularly propeller meters, placed downstream. Moreover, it was doubtful that air admitted to this region would reach all critical zones of local cavitation.
The information obtained from the valve investigation is very useful as design criteria for irrigation-distribution systems where valves are used for regulating the releases.
Eight Years of Experience With Austenitic Steel Piping Materials at Elevated Steam Conditions
Authors: Fairchild F. P. 
Published: February 2022

Abstract
In order to give perspective to the present status of the development of the art, the author presents a factual record of experience with austenitic, heavy-wall, steel piping materials, some of which have been in service since 1948, at elevated steam conditions, in the electric generating stations of Public Service Electric and Gas Company in New Jersey. He describes some of the welding techniques which have been developed over this period and points out some of the areas in which there is need of further development.
Austenitic Steels in High-Temperature Steam Piping
Authors: Curran R. M. , Rankin A. W. 
Published: February 2022

Abstract
A review is presented of the operating experience and service difficulties with austenitic steel turbine piping at the 1050 F and 1100 F temperature levels. Reasons are advanced for the difficulties encountered and recommendations are made to prevent recurrence of these difficulties in future installations.
Application of Digital Computers to Bearing Design
Authors: Sternlicht B. , Maginniss F. J. 
Published: February 2022

Abstract
This paper describes the application of modern digital computing equipment to a study of the operating characteristics of journal and thrust bearings. Results of such a study are used in the design of these bearings. As originally programmed for the Card Programmed Calculator, approximations to the pressure distribution, side leakage, and total load in journal bearings were made under the assumptions of rigid bearings and constant temperature. Present development of the type 650 Magnetic Drum Calculator permits a more rigorous solution accounting for variations in viscosity and density of the lubricant, as well as any prescribed shape of the oil film. Faster and more precise solutions are possible both for thrust and journal bearings. In addition to the calculation of pressure, temperature profile, flow, and load, results for the thrust bearing include a determination of the moments acting on the bearing sector, and a consequent locating of the center of pressure. A numerical example and a computer flow chart are included as guides to the design engineer. Operating techniques, time, and cost factors also are discussed to throw light on the application of a computer from both the engineering and economic standpoints. A derivation of the governing equations in dimensionless form is contained in the Appendix.
New Finite-Difference Technique for Solution of the Heat-Conduction Equation, Especially Near Surfaces With Convective Heat Transfer
Authors: Elrod H. G. 
Published: February 2022

Abstract
Finite-difference methods have come into wide use for solving special problems including transient-heat conduction. Dusinberre has ably presented the possibilities of finite-difference methods. The success of most such methods depends on the existence of a certain degree of uniformity of behavior of the temperature over the finite intervals of both space and time selected for the computation process. In some cases, however, this required uniformity constitutes a handicap since temperatures are changing so rapidly that inconveniently short time intervals have to be chosen. This paper represents an effort to develop a finite-difference method free from the foregoing defect.
Heat Transfer to Laminar Boundary Layers With Variable Free-Stream Velocity
Authors: Seban R. A. 
Published: February 2022

Abstract
Heat-transfer coefficients have been determined for the laminar boundary layer of a two-dimensional subsonic flow of air over a flat plate. By the agency of blisters attached to the wind-tunnel wall the boundary layer, formed under almost constant free-stream velocity, was subjected to a strong acceleration which produced a three to four-fold increase in the free-stream velocity, followed by a moderate deceleration. Maximum velocities ranged from 260 to 900 fps. The heat-transfer results are correlated on the basis expected for laminar flow and it is further demonstrated that a prediction method based on constant fluid properties gives satisfactory correspondence with experiment.
Rate of Temperature Change of Simple Shapes
Authors: Paschkis Victor , Hlinka J. W. 
Published: February 2022

Abstract
Charts have been prepared showing rates of temperature change in simple shapes plotted against temperature. Additional curves show time values, so that one graph yields any of the three relationships: Rate-temperature, rate-time, temperature-time. Samples of the charts are shown, examples of use are given, and limits of the graphs are tabulated. Methods used in establishing the charts are given.
Skewed Boundary-Layer Flow Near the End Walls of a Compressor Cascade
Authors: Moore R. W. , Richardson D. L. 
Published: February 2022

Abstract
Turbulent end-wall boundary layers with considerable skewness are caused by the relative motion of adjacent blade rows in an axial compressor. Flow conditions similar to those near the hub of an axial-compressor rotor were produced in a stationary cascade of blades, and the results of extensive measurements of boundary-layer flow between the blades are presented. An estimate based on the data of the values of terms in the momentum integral equation in the free-stream direction shows the importance of the crossflow in determining boundary-layer growth. A qualitative description of end-wall flow is given.
An Experimental Study of Centrifugal-Pump Impellers
Authors: Acosta A. J. , Bowerman R. D. 
Published: February 2022

Abstract
Experimental investigations were made on four two-dimensional impellers and on a well-designed commercial three-dimensional Francis impeller. The over-all performance of each of these impellers was measured and internal-energy loss and pressure-distribution data were also obtained for several impellers. The exit angle of the two-dimensional impellers was fixed and the inlet angle was systematically varied. However, the hydraulic characteristics of these impellers were all found to differ, the source of the variation being in the various loss distributions and hence internal flow patterns in the impellers. The two-dimensional and three-dimensional impeller-loss distributions were also different. The Francis-impeller performance agreed better with potential theory than that of the two-dimensional impellers, and it is concluded that the different loss distributions of the two types are responsible.
Computer Representations of Engineering Systems Involving Fluid Transients
Authors: Ezekiel F. D. , Paynter H. M. 
Published: February 2022

Abstract
This paper deals with the applications of modern analog and digital computing machines to engineering solutions of fluid-transient problems. It is not concerned with the structural or operating details of the computers themselves. Rather, described here are methods for computer representations of various physical elements commonly used in hydraulic and pneumatic systems such as conduits, valves, pumps, and so forth. These are presented in such forms that they can be incorporated readily as component parts into a simulated engineering installation. Such methods permit rapid determination of critical dimensions as well as ready exploration of alternatives for balances between cost and performance.
Creep Characteristics of Type 347 Stainless Steel at 1050 and 1100 F in Tension and Compression
Authors: Manjoine M. J. 
Published: February 2022

Abstract
Cold-drawn and stress-relieved Type 347 heavy-wall tubing flows plastically at service temperatures (1050-1100 F) when subjected to a stress below the 10,000-hr rupture strength. Precipitation induced by the strain and temperature conditions causes an extended period of abnormally high creep resistance. The duration of this period increases with decreasing stress and is longer for compression than for tension. The creep and rupture strengths for service duration over 10,000 hr are poorer than those reported for Type 347 annealed bar stock.
Electrical Effects Accompanying the Stick-Slip Phenomenon of Sliding of Metals on Plastics and Lubricated Surfaces
Authors: Sohl G. W. , Gaynor J. , Skinner S. M. 
Published: February 2022

Abstract
The electrical transients which accompany the stick-slip phenomenon in boundary lubrication have been investigated by an apparatus which permits simultaneous oscillographic measurement of any two of the following: The instantaneous load, the instantaneous frictional drag, the electrical transient potentials during the stick-slip motion. The phenomenon has been investigated with unlubricated metal-metal contact using four metals in various combinations, lubricated metal-metal contact using various combinations of metals and five lubricants, and metal-plastic contact; in all cases, the contact was a sliding contact at low speed, since this accentuates the stick-slip phenomenon. Definite time correlation between the mechanical stick-slip and the electrical transients has been found. The characteristics of the electrical discharge appear to favor a charge-discharge mechanism rather than a thermoelectric potential or a dielectric breakdown mechanism, although further experiments are necessary to provide unambiguous proof of such a conclusion. Certain related frictional experiments were performed which, however, also favor such a mechanism.