bluuebunny/crossref_metadata_2025 huggingface dataset:
An Approach to the Economic Problem of Matching Condenser Surface With Exhaust-Annulus Area
Authors: Wilson W. A. , Malouf L. G.
Published: February 2022

The concept of economic balance as related to power-plant optimization is discussed. Its application to the problem of choosing appropriate exhaust-annulus and condensing surface areas is developed in detail. These areas are related to each other for three circulating-water temperatures and several unit-cost ratios. The exhaust conditions and the rate of change of stagnation enthalpy with investment are presented as functions of these areas.
Effect of Size on the Inlet-System Dynamics in Four-Stroke, Single-Cylinder Engines
Authors: Tsai D. H.
Published: February 2022

This paper describes a study of the problem of dynamic similarity in inlet systems of four-stroke, single-cylinder engines with long inlet pipes. A similarity rule formulated from a consideration of unsteady, isentropic, one-dimensional flow of a compressible fluid in the inlet pipe is checked by experiments.
Study of Pneumatic Processes in the Continuous Control of Motion With Compressed Air—II
Authors: Shearer J. L.
Published: February 2022

The results of analytical and experimental work reported in Part I (Paper No. 55—IRD-4) are employed in the analysis of a valve, ram, and mass-load system. This complete servomotor system is analyzed for its response to small changes of valve opening and to changes of external load force, and a simple electronic analog of the system is used to study means of providing adequate system damping. The results indicate that connecting a flow resistance and tank of suitable size to each end of the ram permits a stabilizing transient flow to each of the tanks when the ram pressures are changing rapidly. Design charts provide means of quickly finding the roots of the third-order characteristic equation for the system with transient-flow stabilization.
The Chemical Deaeration of Boiler Water—The Use of Hydrazine Compounds
Authors: Leicester J.
Published: February 2022

The preliminary stages in an experimental study of the reaction rates of the hydrazine-oxygen system are described. The work is continuing along four main lines, a bench-scale study of the mechanism of and the factors influencing the reaction, an investigation of reaction rates in a static autoclave system, study of reaction rates in a pilot-plant high-pressure boiler, and a series of full-scale boiler trials. The simple reaction between hydrazine and oxygen has been shown to be far more complex than was at first thought to be the case, and perhaps the most important conclusion is that even in dilute solutions this can proceed as a surface reaction. The experiments serve to indicate that in the present state of our knowledge, it would not appear possible to predict the efficiency of the reaction for a universal boiler application and that, to achieve the desired result, some form of reaction catalyst may have to be developed.
Factors Influencing the Notch-Rupture Strength of Heat-Resistant Alloys at Elevated Temperatures
Authors: Carlson R. L. , MacDonald R. J. , Simmons W. F.
Published: February 2022

Stress-rupture tests were conducted on notched and unnotched or plain bars of S-816, Inconel “X” Type 550, and Waspaloy alloys at test temperatures ranging from 1200 to 1600 F. The notched specimens had 50 per cent, 60-deg, V-notches with the root radii ranging from 0.005 to 0.100 in. In some tests, as many as three notches of different root radii were used. The test results indicated that S-816 alloy was notch-strengthened by all of the notches used in the temperature range from 1350 F to 1600 F. Inconel “X” Type 550 was always notch-strengthened by all of the notches only at the test temperature of 1600 F. Waspaloy was always notch-strengthened by all notches only at the temperature of 1500 F. Both Inconel “X” Type 550 and Waspaloy could be notch-strengthened for some test conditions (notch sharpness and time) at temperatures below 1600 and 1500 F, respectively. Factors considered to have an influence on stress-rupture behavior have been studied and the results are included. The factors investigated are notch geometry, notched and unnotched ductility, the modes of deformation and fracture, metallurgical changes, and surface condition. The influence of some of these factors can vary considerably from alloy to alloy. It does not appear possible, therefore, to evaluate completely the notch and unnotched stress-rupture behavior of a given alloy by any simple method. Rather, an evaluation should be based upon the combined consideration of those factors that are influential in each individual case.
Flow of Saturated Boiler Water Through Knife-Edge Orifices in Series
Authors: Monroe E. S.
Published: February 2022

This paper presents the results of experiments with the flow of saturated boiler water through from one to four knife-edge orifices arranged in series. A useful equation is developed to conform to both the available published data and the author’s experimental results when the back pressure on the orifice is at or near barometric condition.
Journal-Bearing Performance for Combinations of Steady, Fundamental, and Low-Amplitude Harmonic Components of Load
Authors: Shawki G. S. A.
Published: February 2022

This paper presents the results of an experimental study of the effect, on journal-bearing performance, of superposing the low-amplitude harmonic to fundamental and steady components of a vertical cyclic bearing load of the form P=P0+P1sin (ω1t)+Pnsin (nω1t+ψ) Amplitude ratio values (Pn/P1) of between about 0.3 and 0.4 and frequency ratio values (n) of 2, 3, and 4 are considered. Test results exhibit a bearing performance somewhat similar to that obtained with sinusoidally alternating and fluctuating loads with critical changes in performance, at (ω1/ω) (ratio of the rate of load application to that of journal rotation) slightly less than 0.5, of a character mainly dependent on the ratio (P1/P0). The striking phenomenon encountered in the tests, however, is the appearance of secondary critical changes in the performance at submultiples of the one-half speed ratio, namely, at (ω1/ω) slightly less than 0.25, 0.167, and 0.125 for second, third, and fourth superposed harmonic components of load. An explanation of this behavior is suggested. Further work on the subject is proceeding.
Studies in Lubrication—XI: Slider Bearing With Transverse Curvature; Exact Solution
Authors: Ying A. S. C. , Charnes A. , Saibel E.
Published: February 2022

An exact solution is developed for the Reynolds equation in the hydrodynamical theory of slider-bearing lubrication with side leakage for film thickness varying exponentially both in the direction of motion and symmetrically perpendicular to this direction. This solution is in the form of a rapidly convergent series from which calculations for the pressure distribution, total bearing load, frictional force, and so on, may be made conveniently for all length-to-width ratios, all entrance-to-exit clearance ratios, and all center-to-side clearance ratios. The results which were obtained previously by the perturbation method are shown to be quite accurate for small ratios of center-to-side clearance and, for the larger ratios, the error of the perturbation method is calculated. In fact, the present exact solution turns out to be as convenient to apply as the former approximate one and is recommended for practical consideration.
On the Theory of Discharge Coefficients for Rounded-Entrance Flowmeters and Venturis
Authors: Rivas Miguel A. , Shapiro Ascher H.
Published: February 2022

A theory of rounded-entrance flowmeters, based on a consideration of the potential and boundary-layer flows in a converging nozzle, is constructed. Curves are presented showing the discharge coefficient as a function of diameter Reynolds number, with the “total equivalent length-diameter ratio” of the nozzle as a parameter. The equivalent frictional length-diameter ratio of the contraction section of the ASME long-radius nozzle is presented. The theoretical curves of discharge coefficient versus diameter Reynolds number are in good agreement with experiment over a range of Reynolds number from 1 to 106. The theory provides a rational framework for correlating and extrapolating experimental results; it shows the effects of contraction shape and location of pressure taps; it furnishes values of discharge coefficient for untested designs; and it suggests precautions to be taken in design, installation, and operation.
A Method of Predicting the Effects of Notches in Uniaxial Fatigue
Authors: Dirkes W. E.
Published: February 2022

This paper approaches the problem of correlating notched and unnotched test data from observations of how the material may be considered to be affected under repeated stresses. A semigraphical method of extrapolating notched test data is developed. Although data available do not conclusively prove the observations reported herein, neither does presently available information refute the views presented. Individual observations are gathered together to form a picture which is intended as an aid to designers in visualizing possible trends even though complete test data are not available.
Quantitative Evaluation of Thermal-Shock Resistance
Authors: Manson S. S. , Smith R. W.
Published: February 2022

The dependence of thermal-shock resistance on two parameters k and σf/Eα (when k is conductivity, σf the fracture stress, E the elastic modulus, and α the coefficient of thermal expansion) is experimentally demonstrated by the fact that the relative ratings of two materials may change with a change of quench severity. The theory of thermal-shock resistance of a disk quenched at the periphery is developed, making use of the results of Jaeger. Two criteria for failure are considered; namely, the maximum normal-stress criterion, and the criterion of maximum “risk of rupture” based on the Weibull statistical theory. Equipment for subjecting these specimens to a wide range of quench severities of known surface heat-transfer coefficients is described, and results are presented for thermal-shock tests of steatite and glass disks. The results for steatite are then utilized for determination of thermal-shock parameters by four independent methods, the results showing good agreement.
A Survey of Aerodynamic Excitation Problems in Turbomachines
Authors: Sabatiuk A. , Sisto F.
Published: February 2022

The important blade-excitation phenomena in turbomachines are reviewed with respect to the theory extant in the literature and with respect to typical experimental results. The mechanisms of flutter, forced excitation, and rotating stall are discussed broadly and the importance of subharmonic resonance in turbine blades is introduced. Finally, general topics worthy of furthur consideration are enumerated and avenues for future research are delineated.
A New Electrical Analog Method for the Solution of Transient Heat-Conduction Problems
Authors: Liebmann G.
Published: February 2022

A new resistance-network analog method for the solution of heat-flow problems under transient conditions is described. In this method, electrical networks represent the difference equations which approximate the differential equations governing the problem to be solved. Temperature is represented by voltage, the spatial features of the problem by a network of parallel resistances, and the thermal constants by series resistances. A solution in steps δt of time is obtained by successive readjustments of potentiometers supplying the voltages to the network. The new method is very flexible, the time interval δt and the thermal constants being adjustable during the progress of the work. It can be applied to problems of considerable complexity. One of its outstanding features is its “stability.” Accuracies of better than 1 per cent can be obtained.
Laminar Pipe Flow With Injection and Suction Through a Porous Wall
Authors: Yuan S. W. , Finkelstein A. B.
Published: February 2022

The effect of injection and suction at the wall on the two-dimensional steady-state laminar flow of a fluid in a porous-wall pipe has been investigated in detail by the solution of the Navier-Stokes equations in cylindrical co-ordinates. An exact solution of the dynamic equations, reduced to a third-order nonlinear differential equation with appropriate boundary conditions, is obtained. A perturbation method was used to solve the latter equation for both small and large flows through the porous wall. The velocity components are expressed as functions of the ratio of velocity through the porous wall to the maximum axial velocity at the pipe entrance, the co-ordinates of the pipe, and the physical properties of the fluid. The results show that the effect of injection at the porous wall of the pipe is to increase the friction coefficient at the wall. For an injection ratio Q/W = 0.01 (500 ≤ Re ≤ 2500) the friction coefficient at the wall is increased by 70–85 per cent over the zero injection case (Poiseuille case).
Self-Excited Vibrations of Systems With Two Degrees of Freedom
Authors: Saljé Ernst
Published: February 2022

The paper reports on an investigation of vibrations of systems with two degrees of freedom. First to be considered is the dynamic behavior of a lathe spindle. Cutting conditions are of influence, and it can be demonstrated that a lathe spindle approximates vibrations in two degrees of freedom. Thereafter, a series of tests is described that were run with turning tools of relatively great overhang and with two degrees of freedom. Finally, the mathematical concept of self-excited vibrations is given. This paper may be considered as a discussion of the particular problems investigated. It does not purport to give a general theory of self-excited vibrations of the cutting processes.
The Dynamic Response of Industrial Thermometers in Wells
Authors: Linahan T. C.
Published: February 2022

Previously published analyses of the dynamic response of thermometers in wells have neglected either the internal distributed well resistance or the internal bulb resistance. This paper considers an “effective” resistance and capacitance of the bulb when it is in a well. The distributed resistance and capacitance of the well are included, and an approximate second-order expression for the dynamic response is developed using a combined analytical and experimental approach. There is also a brief discussion of the film coefficient of heat transfer.
Flow of a Compressible Fluid in a Thin Passage
Authors: Grinnell S. K.
Published: February 2022

Pressure distribution and weight-flow rate can be predicted for laminar compressible-fluid flow in a thin passage by use of the methods presented in this paper. A simplified method can be used readily when the fluid forces due to viscous action predominate over those due to acceleration of the fluid. A more complicated trial-and-error method seems to be required for larger passages where, though the flow may be laminar, the momentum effects due to acceleration of the compressible fluid are appreciable. An experimental apparatus was used to examine the validity of the analytical work. Experimental pressure distributions agree within a maximum deviation of 10 per cent with the theoretical distributions predicted by both the comprehensive and simplified theories. Experimental weight-flow rates agree within a maximum deviation of 50 per cent with predictions of the simplified theory. Dimensionless plots of pressure distribution are presented with experimental curves of flow rate versus pressure ratio for various ratios of passage length L to passage height h. These plots, together with simple equations, have been prepared for direct use by the designer.
The Effect of Oil-Column Acoustic Resonance on Hydraulic Valve “Squeal”
Authors: Ainsworth F. W.
Published: February 2022

An outline is presented of a theory that oil-column resonance is one likely cause of control-valve oscillation. It is shown analytically and experimentally that acoustic resonance of the oil in the lines which are attached to the valve can cause an otherwise stable valve to squeal. Methods of eliminating the oscillation are given.
Determination of Radius of Curvature for Radial and Swinging-Follower Cam Systems
Authors: Kloomok Martin , Muffley R. V.
Published: February 2022

An exact expression is derived for the radius of curvature of disk cams with either radial or swinging followers. Several charts are included which illustrate a quick method for arriving at a solution for a particular cam contour, such as the harmonic.
Measuring the Thermal Diffusivity of Metals at Elevated Temperatures
Authors: El-Hifni M. A. , Chao B. T.
Published: February 2022

The Angström-bar method has been modified and adapted to the measurement of thermal diffusivity of metals for temperatures ranging from 300 to 1050 F. A small, sinusoidal temperature fluctuation is superimposed on the mean temperature of a thin-wall tubular specimen by means of simultaneous heating and cooling at one end. Thermal diffusivity was calculated from the phase shift and amplitude ratio of the temperature waves determined at two measuring stations. The effect of possible surface heat loss is considered. Measurements were made on AISI 1018, 1045, 3140 steels, and 1.1 per cent carbon tool steel. Results obtained for electrolytic tough-pitch copper and 2S aluminum showed good agreement with a recent theory of Storm concerning the variation of thermal diffusivity of simple metals with temperature.
Demineralized Make-Up for 1250-PSI Installation at East Millinocket Mill of Great Northern Paper Company
Authors: Davidson E. F.
Published: February 2022

In 1952 the Great Northern Paper Company planned an increase in manufacturing capacity at its East Millinocket mill from 325 to 900 tons per day of newsprint, necessitating an enlargement of its steam-generating plant. Results of studies showed that new boilers should supply 1250 psi, 850 F steam to noncondensing extraction turbine-generators, and that the maximum amount of by-product power should be generated up to the limitation imposed by steam flow through the turbines as required for process. The problem of supplying relatively large quantities of feedwater make-up of suitable quality was a major consideration. Shortly before 1952, a number of high-capacity water-treatment installations of the demineralizing type had been installed, which provided operational background for justifying the 1250-psi steam plant from this standpoint.
Power Loss in Elliptical and 3-Lobe Bearings
Authors: Pinkus Oscar
Published: February 2022

The power losses for elliptical and three-lobe bearings, both symmetrical and asymmetrical, were derived as functions of the customary bearing parameters and bearing ellipticity. Expressions are given for two cases; one assuming a complete oil film, and one taking into account the incompleteness of the oil film in the diverging sections of the bearing. All equations are for a concentric shaft position, this being a plausible assumption as noncylindrical bearings are mostly used in low load, high-speed applications. For convenience the power losses for the noncylindrical bearings are plotted in comparison with those for cylindrical bearings of clearance c as given by Petroff’s equation. Excellent agreement was found between the theoretical power losses and experimental results in bearings.
Prediction of Lubricating-Oil Viscosities at High Pressures
Authors: Clark O. H.
Published: February 2022

Data from the ASME project on high-pressure viscosity have been applied to test the feasibility of predicting viscosity at high pressures from room-pressure measurements at 100 and 210 F. For ASME test oils graphical relations were developed to predict viscosities up to about 50,000 psi at 100 and 210 F. Two scales were used, according as oils were classified as paraffinic or naphthenic. Discrepancies between measured and predicted values are noted and discussed.
An Experimental and Analytical Investigation of a Differential Surge-Tank Installation
Authors: Gibson W. L. , Shelson W.
Published: February 2022

The performance of a differential surge tank was measured experimentally for various acceleration and retardation conditions, and the results were compared with those obtained analytically. In the experimental investigation, the dynamic pressures at several places in the hydraulic system, together with the turbine-gate positions, were recorded simultaneously on a multichannel oscillograph. For comparison, the corresponding water-hammer pressures and mass flows in the system were calculated by recognized step-by-step processes, adequate numbers of steps being made practicable by the use of high-speed digital computers. The calculated results agreed closely with those determined experimentally.
Very Short Journal-Bearing Hydrodynamic Performance Under Conditions Approaching Marginal Lubrication
Authors: Kreisle L. F.
Published: February 2022

This paper is a presentation of experimental data concerning the hydrodynamic performance of short journal bearings under conditions approaching zero minimum oil-film thickness near or in the region of boundary lubrication. Experimental data are presented for short journal bearings with length-to-diameter ratios between 1/2 and 1/53. Theoretical performance of short journal bearings by several theories is compared with experimental findings of extremely short bearings. Six different load numbers are defined and are found to be useful in predicting and analyzing the performance of short journal bearings.
Effect of Combustion-Resistant Hydraulic Fluids on Ball-Bearing Fatigue Life
Authors: Cordiano H. V. , Cochran E. P. , Wolfe R. J.
Published: February 2022

Phosphate ester, phosphate ester-base, and water-glycol-base combustion-resistant fluids and a petroleum oil were investigated to determine the relative effects of the fluids, used as flood lubricants, on the life of angular-contact ball bearings. Bearing life was lower in the combustion-resistant fluids than in oil, ranging from 58 per cent of the life in oil for the phosphate ester, to 6 per cent for the water-base fluid. Fatigue failures of the bearing races were prevalent for all fluids and additional investigations are required to determine the causes of the wide variation in bearing life in the various fluids.
Operating Characteristics of High-Speed Ball Bearings at High Oil-Flow Rates
Authors: Moore C. C. , Jones F. C.
Published: February 2022

Using 1005 petroleum oil as a lubricant, 202, 203, and 204-size ball bearings were operated in a speed range of between 0.6 to 1.7 × 106DN value. Under lightly loaded conditions, oil-flow rates were varied between 1 and 500 range while friction power, oil-inlet, and outer-race temperatures were measured at speeds between 30,000 and 100,000 rpm.
Thermal-Cycling Test of a Hot Spot on a Vessel
Authors: Randall P. N. , Lang H. A.
Published: February 2022

This paper presents the results of laboratory tests which simulated the effect of repeated cycles of heating and cooling of a spot on a catalytic-cracker regenerator shell. A specimen was made to resemble in all feasible respects a 6-ft-square piece of a cylindrical shell of a regenerator, including welded seams and vapor stops. After 50 cycles of heating to 900 F at the center of the spot for 1 or 2 days, then cooling to near room temperature, the plate was radiographed, its microstructure examined, and its mechanical properties determined. No evidence of cracking or of deterioration of the metallic structure was observed. Some distortion was produced by the first few cycles of heating but continued cycling did not produce further distortion.
Resistance Coefficients for Accelerated and Decelerated Flows Through Smooth Tubes and Orifices
Authors: Daily J. W. , Hankey W. L. , Olive R. W. , Jordaan J. M.
Published: February 2022

This paper is a summary of the results of investigations of the drop in potential and boundary resistance in unsteady motion for cases of surface resistance caused by boundary shear stresses and cases of form-type resistance associated with the high shear and generation and diffusion of turbulence accompanying jet formation. These cases were obtained using uniform diameter conduits and orifices in conduits. From tests in the MIT unsteady flow water tunnel, the effects of accelerated and decelerated flows were studied. In the case of flow through a uniform tube, it was found that the boundary resistance at any instant during accelerated motion was slightly greater than the equivalent steady-state case while, for decelerated motion, it was slightly less. In the case of flow through orifices, it was found that the combined resistance of the orifice and the conduit was less during accelerated motion and more during decelerated motion than for the equivalent steady-state cases.
Process Design of Tubular Heaters
Authors: Mekler L. A.
Published: February 2022

Factors defining the principal process requirement of tubular heaters—the “time-temperature effect,” and means of obtaining different rates of heat input in portions of the coil of a heater to produce the desired time-temperature relationship are discussed. The most popular types of process tubular heaters used, at present, are briefly described and evaluated as to their general adaptability to operate with single and multiple streams and varying heat-input rates. Numerical examples of the effects of change in spacing of tubes and the use of single and double-row banks are given.
Preliminary Investigation of Minimum Oil-Feed Rates for Fluid-Film Conditions in Journal Bearings
Authors: Fuller D. D. , Sternlicht Beno
Published: February 2022

Many industrial bearings do not operate with an abundant supply of lubricant. Bearings that are fed with wicks, pads, and drop-feed oilers, for example, are found in this category. It has been demonstrated that a certain volume of lubricant must be supplied to a journal bearing to permit the formation of a complete hydrodynamic fluid film. Since it is generally desirable to have bearings operate with a fluid film in order to develop the least friction and wear, the question of determining the minimum rate of feed in order to insure such operation is of some importance. The work described in this paper has resulted in a method which appears promising for predicting the minimum feed rate for a journal bearing. The minimum feed rate is evaluated in terms of speed, load, clearance, and size of bearing. The method is based on a theoretical analysis supplemented by experimentally determined constants.
Measurement of Mean Fluid Temperatures
Authors: Trefethen Lloyd
Published: February 2022

It is shown that the mean temperature obtained for a section of a heat exchanger varies with the technique of measurement. Because of axial heat flow, neither a mixing box, nor temperature and velocity probes in a turbulent fluid, will give the energy mean temperature of the moving fluid. For long, thin-walled, uniformly heated tubes, the inherent discrepancy due to the use of a mixing-box mean temperature is negligible if RePr > 30. The tube and apparatus, however, may have an axial conductivity many times that of the fluid, and it is shown that some of the experimental data for liquid metals may have been influenced by this axial heat-flow discrepancy.
Metal Transport in Liquid-Water Systems and Effect on Heat Transfer
Authors: Datsko S. C.
Published: February 2022

A series of tests was conducted to determine the effects on heat transfer caused by the corrosion by water of zirconium tubes and by the deposition of corrosion products of a stainless-steel system on the zirconium-tube walls. Tests were conducted at water velocities from 2 to 30 fps and beat-flow rates from 30,000 to 500,000 Btu hr-sq ft of surface in single-tube, countercurrent, water-to-water heat exchangers. The heating-water temperature ranged between 500 and 620 F and the cooling-water temperature between 450 and 500 F. Several water treatments, such as deionization and oxygen or hydrogen additions, were investigated. Results of these tests are given in the paper.
Combustion Calculations for Multiple Fuels
Authors: Buna Tibor
Published: February 2022

This paper presents a procedure for the calculation of the composite analysis and heat content of a plurality of fuels fired in combination, with special emphasis on the difficulties often encountered by the test and operating engineers in obtaining reliable fuel-flow data. The propagation of uncertainties in the basic quantities defining alternate efficiencies are discussed, and a procedure for the graphical representation of the CO2-O2 excess-air relationship for dual fuels is developed.
The Viscosity of Steam, Heavy-Water Vapor, and Argon at Atmospheric Pressure Up to High Temperatures
Authors: Bonilla C. F. , Wang S. J. , Weiner H.
Published: February 2022

Because of the increasing emphasis on high-temperature processes and high-speed flight, the physical properties of gases at high temperatures and atmospheric pressures have acquired considerable importance. A recent study (1) of the viscosity of steam was carried out over the range of 450 to 1200 deg C in a heat-jacketed apparatus. At that point failure of refractory supports in the furnace precluded higher and lower temperature runs. It was decided to repeat this work with the same type of capillary efflux viscometer but a stronger support for the capillary, and also cover lower and higher temperatures. The viscosity of D2O vapor, not found in the literature, was also determined. In addition, the viscosity of argon was measured, in view of expressed doubts (2) as to the accuracy of Vasilesco’s results.
Water-Hammer Calculations and Test Results—Owens Gorge Power Plant Penstocks
Authors: Bratfisch A. E. , Cartwright K. O.
Published: February 2022

Water-hammer calculations were made for the three penstocks of the Owens Gorge Power Plants to determine proper governor and relief-valve time settings. Test results show good agreement with the calculations. Computing methods, complete test results, and an analysis of these results are included in this paper. A brief discussion of the operation of the surge chambers for these plants is also included.
Pullman-Standard’s Train X
Authors: Gray T. C.
Published: February 2022

The author establishes the several basic objectives motivating introduction of Train X, and presents in digest form a description of the more important design features calculated to meet these objectives, including a discussion of single-axle suspension, automatic coupling, structure, acoustic treatment, and so on. He lays particular stress on the importance of cost reduction (initial, operating, and maintenance) and emphasizes the extent to which design was influenced by this factor and the need to provide maximum passenger comfort and acceptance.
Validity of Time-Compensated Temperature Parameters for Correlating Creep and Creep-Rupture Data
Authors: Garofalo F. , Smith G. V. , Royle B. W.
Published: February 2022

Several time-compensated temperature parameters, which were proposed as dependent only on the initial stress, are discussed with relation to time of creep rupture and to minimum and average creep rates. The so-called master “curve” is discussed in terms of experimentally determined relationships. In checking the validity of the proposed parameters, using experimental results for several ferritic and austenitic steels, it is found that these parameters are not single-valued functions of the initial stress over wide ranges in stress, and the existence of a master curve for these parameters is doubtful.
Mechanical Properties at Elevated Temperatures of Ductile Cast Iron
Authors: Foley F. B.
Published: February 2022

Interest in the elevated-temperature properties of the relatively new engineering metal, ductile cast iron, has prompted the gathering together of data (1 to 5) on the subject and the correlation of them on a uniform basis. In correlating the values obtained by the several laboratories on different melts of somewhat different compositions, use is made of the equation applied originally in the evaluation of effects of time and temperature in the tempering of steel and later adapted by Larson and Miller (6) to the determination of stress rupture and creep values for various conditions of temperature, load, and time from data which had been obtained under limited sets of conditions. The paper demonstrates the application of the Larson-Miller method.
A Practical Pulsation Threshold for Flowmeters
Authors: Head V. P.
Published: February 2022

Pulsation intensity Γ is defined as the ratio of extreme flow variation to average flow. An intensity Γ = 0.1 is recommended as a practical pulsation threshold below which the performance of all types of flowmeters will differ negligibly from the mathematical ideal of steady flow. An equation suitable for estimating the error range at various intensities is presented, and the problems of correlation of attenuator performance and meter response are considered.
The Influence of Shank Area on the Tensile Impact Strength of Bolts
Authors: Love John , Pringle O. A.
Published: February 2022

The effect of reduction of shank cross-sectional area on the tensile impact strength of 5/16, 3/8, and 7/16-in. steel bolts was investigated experimentally. Low-carbon 3/8-in. bolts with rolled threads absorbed maximum impact energy when the ratio of shank area to thread-root area was equal to 1.23. Heat-treated medium-carbon 3/8-in. bolts absorbed maximum impact energy when the ratio of shank area to thread-root area was equal to 1.17 for shanks reduced by drilling or 1.12 for shanks reduced by turning. Results for other sizes were similar. It was concluded that for maximum energy absorption the shank area should approximately equal the mean or tensile-stress area of the threads, with minor corrections to compensate for work hardening due to thread rolling or surface oxidation resulting from heat-treatment.
Report of the Investigation of Two Generator Rotor Fractures
Authors: Schabtach C. , Fogleman E. L. , Rankin A. W. , Winne D. H.
Published: February 2022

The recent fractures of two large generator rotors led to the initiation of an extensive investigation to clarify the causes of the trouble. This paper describes the various phases of the investigation, which included a thorough study of features of design and manufacture and the characteristics of the rotor materials, together with a presentation of the results.
Large Rotor Forgings for Turbines and Generators
Authors: Mochel N. L. , Peterson R. E. , Conrad J. D. , Gunther D. W.
Published: February 2022

The paper discusses turbine-generator rotor forgings. It includes a brief history of the development of present designs, materials used, manufacturing methods, and the various testing practices employed. Special reference is made to low-pressure rotor construction. A discussion on types of instability encountered in turbine rotors is included. The paper includes a section on design criteria dealing with static considerations, fatigue considerations, and reports the results of several model bursting tests. The importance of proper alignment of rotor shafts is covered.
Acceptance Guides for Ultrasonic Inspection of Large Rotor Forgings
Authors: Rankin A. W. , Moriarty C. D.
Published: February 2022

This paper discusses the problem of establishing criteria, based on ultrasonic examination, for the acceptance or rejection of large rotor forgings. From the results of trepanning and cutting up a number of such forgings, guide lines are established for determining when trepanning should be used for identification of the ultrasonic discontinuities.
Work of the Task Group on Brittle Failure of Steel Forgings
Authors: Schaefer A. O.
Published: February 2022

Specifications for steel products as well as the methods of testing and inspecting steel products are entrusted by the American Society for Testing Materials to Committee A-1. This is the oldest and one of the largest technical committees of the Society. The work of the committee is, in turn, delegated to a number of subcommittees covering various products such as sheet, plate, pipe, bars, etc. Steel forgings are the responsibility of Sub-Committee VI. The current yearbook of the Society indicates that Sub-Committee VI has 65 members. This paper covers the activities of Sub-Committee-VI Task Force on Brittle Failure of Steel Forgings.
Heat Transfer and Temperature Distribution in Laminar-Film Condensation
Authors: Rohsenow W. M.
Published: February 2022

Most of the analyses of laminar-film condensation since Nusselt’s pioneer paper have assumed a linear-temperature distribution within the film. Bromley performed an analysis allowing for a nonlinear temperature distribution but omitting the effect of cross flow within the film. His result is in variance with the result obtained here.
Scoring Characteristics of Thirty-Eight Different Elemental Metals in High-Speed Sliding Contact With Steel
Authors: Roach A. E. , Goodzeit C. L. , Hunnicutt R. P.
Published: February 2022

A study has been made of the “score resistance” of 38 elemental metals tested as slider bearings against 1045 steel disks. It was found that the metals which have the best score resistance against steel are the B-subgroup metals which are either insoluble with iron or else form intermetallic compounds with iron.
Some Aspects of High-Suction Specific-Speed Pump Inducers
Authors: Ross C. C. , Banerian Gordon
Published: February 2022

Some aspects of the design and performance characteristics of high-suction specific-speed pumps (cavitating inducer) are discussed. Although conventional pump-suction specific speeds are limited by incipient cavitation limits, the properly designed cavitating inducer can operate at values of suction specific speeds many times that limited by incipient cavitation. Owing to the restricted nature of this material, the authors regret leaving out much of the design information.
Fly-Ash Refiring
Authors: Feeley F. G.
Published: February 2022

Over a period of 30 years a vast expansion of plants of the Carbide and Carbon Chemicals Company has taken place on the Kanawha River, South Charleston, W. Va. The accompanying growth of power plants has created a fly ash-disposal problem. Three years ago when the addition of a new 250,000-lb-per-hr boiler installation was contemplated, it was decided to incorporate refiring features which largely would eliminate the difficulty. A description of the installation and its performance is given in the paper.
Test of an Experimental Coal-Burning Turbine
Authors: Mordell D. L. , Foster-Pegg R. W.
Published: February 2022

In 1949 one of the authors suggested’ that, by the use of the exhaust-heated cycle for a gas-turbine power plant, the new problems and difficulties then besetting those who were trying to produce a coal-burning gas turbine, including (a) feeding of pulverized coal under pressure, (b) burning pulverized coal under pressure, (c) gasifying coal under pressure, (d) separating ash from high-temperature gases, (e) establishing the tolerance of turbine blades to ash erosion, might be replaced by two problems different in degree but not in nature from those encountered in the design of boilers, namely, (1) combustion of coal in a furnace at essentially atmospheric pressure; (2) heating of a compressed gas by transfer of heat from hot combustion products. It appeared that adaptation of the existing technology to the gas-turbine conditions should prove easier than the evolution of a completely new technology. It was recognized, however, that the differences in degree made it impossible to design, with confidence, a power plant which might be expected to be immediately successful. It was, therefore, suggested that a purely experimental plant should be designed, constructed, and tested to lay the foundations for a future successful design. Representatives of the two major Canadian railroads considered that this proposal might lead to the evolution of a coal-burning gas-turbine locomotive that would play a useful part in their operations. The Dominion Coal Board felt that such a program might lead to the development of improved ways of utilizing coal and thereby effectively help the Canadian coal industry. The Department of Mines and Technical Surveys then placed a contract with McGill University for such a program to be carried out under the senior author’s direction. Since that time, a vast amount of work has been done. The experimental plant has been built and has now completed its first series of tests. A great deal of theoretical design and economic consideration has been given to possible applications. The present paper reviews what has been done, and discusses the lessons that have been learned and their application in the future.
Development of High Performance Vertical Falling Film Plastic Dehumidifier Exploiting Surface Modification Technique
Authors: Khan Rehan , Patil Digvijay , Kumar Ritunesh
Published: February 2022

Plastics as air–liquid desiccant contacting surfaces are being explored as a promising alternative to metallic surfaces in falling film towers. Nevertheless, the poor wetness of plastics has severely restricted its extensive practical applicability. In the current experimental study, a surface modification technique is employed to enhance the dehumidification performance of single polypropylene (PP) plastic plate surface. Dehumidification ability of three kinds of plastic plate surface: plain PP plate, modified PP plate A, and modified PP plate B were investigated and compared in an adiabatic vertical falling film tower. It was found that the best modified PP plate offered 48.1–127.0% improvement in dehumidification effectiveness as compared to the plain PP plate with an average improvement of 83.3%. Furthermore, a new correlation is developed to predict the dehumidification effectiveness of plastic and metallic surfaces of adiabatic/nonadiabatic falling film tower by incorporating the wetting factor and sensible cooling information in the correlation equation. The new approach takes into account the sensible cooling (nonadiabatic absorber) of the desiccant solution in the upper half of the absorption column. The proposed correlation demonstrates excellent accord with 11 experimental datasets, with an average error of 12.7%.
Hard ticks (Acari: Ixodidae) infected by rickettsias: the first record of Rickettsia aeschlimannii (Rickettsiales: Rickettsiaceae) in Iran
Authors: Saman Esmail Amiri Ghanat , Chegeni Asadollah Hosseini
Published: February 2022

We aimed to investigate the molecular evidences on the role of ticks as vectors of Anaplasma and spotted fever group (SFG) Rickettsia species in southeastern Iran. A total of 815 tick samples were collected from different geographical regions of southern Kerman province. A 524-bp fragment of 16S rRNA and a 464-bp fragment of major surface protein 4 (msp4) of Anaplasma, a 962-bp fragment of outer membrane protein A (ompA) of rickettsiae, as well as an amplicon (ca. 800-bp) of internal transcribed spacer 2 (ITS2) of ticks were amplified by PCR technique. Ten nucleotide sequences, including three ompA, three ITS2, four Anaplasma (16S rRNA and msp4) were analyzed with BLASTn and phylogenetic software. According to ITS2 nucleotide sequences three tick species Hyalomma asiaticum, H. rufipes and Rhipicephalus sanguineus complex were identified. Rickettsia aeschlimannii was detected from Rh. sanguineus complex and H. rufipes, as well as A. ovis and a SFG Rickettsia was found in Rh. sanguineus and H. asiaticum, respectively. The present study reemphasizes the potential role of Rh. sanguineus complex in the natural cycle of ovine anaplasmosis in southeastern Iran. Our results also confirmed the presence of R. aeschlimannii in Rh. sanguineus complex and H. rufipes ticks for the first time in Iran. These results suggest a possible role of these ticks in the transmission cycle of R. aeschlimannii in southeastern Iran.
Health Literacy Levels of Collegiate Student-Athletes
Authors: Roberts Jodee M. , Rivera Matthew J. , Winkelmann Zachary K. , Eberman Lindsey E.
Published: February 2022

This study used a web-based survey and a cross-sectional design to investigate the health literacy levels of collegiate student-athletes. The survey included a demographic questionnaire and the Short Test of Functional Health Literacy Assessment, which scores an individual’s ability to understand relevant health care information. We calculated descriptive statistics for demographic characteristics and Short Test of Functional Health Literacy Assessment scores. All participants (n = 160) displayed adequate health literacy (mean = 34 ± 2; range = 27–36; adequate = 160/160, 100%). The mean Short Test of Functional Health Literacy Assessment score for both White (range = 27–36; adequate = 133/133, 100%), and non-White participants (range = 28–36, adequate = 27/27, 100%) was 34 ± 2. Health care professionals should feel confident in collaborating with individual patients throughout the decision-making process.
Acute Kidney Injury in a High School Athlete
Authors: Portlock Tessa , Hunt Natalie A. , Zaremski Jason L. , Merchant Asim , Tripp Patricia M.
Published: February 2022

A 17-year-old African American male high school athlete was diagnosed with an acute kidney injury secondary to severe dehydration following a football game. After administering intravenous fluids and obtaining multiple blood tests, the athlete was released from the emergency department. Following the care in the emergency department, the athlete was restricted from all physical exertion for 2 weeks. Furthermore, after a gradual, monitored return-to-play protocol, he returned back to sport without complications. This case is unique in its presentation because acute kidney injury is often found, in sports medicine literature, to occur in older endurance athletes; it is rarer to encounter it in the adolescent population within a team sport. This case also highlights the need for interprofessional collaboration in order to enhance and facilitate a safe return to play for all athletes.
Anterolateral Ligament Reconstruction in a Collegiate Lacrosse Athlete
Authors: Routman Carly , Stich Tommy , Zippieri Giorgio , Moser Michael , Tripp Patricia M.
Published: February 2022

A 21-year-old female lacrosse athlete with a prior left knee anterior cruciate ligament reconstruction sustained an acute, noncontact injury to the same knee during practice. Clinical examination showed adequate sagittal plane joint stability, with reduced rotational support. Radiologist’s findings following magnetic resonance imaging suggested an increased signal at the anterior cruciate ligament, presence of a subacute medial meniscus tear, and Grade II strain of the semimembranosus tendon. Surgical intervention included anterolateral ligament reconstruction and debridement. The clinical team used patient-reported outcome measures and symmetry of strength and balance to progress therapy. Although cleared for exercise, her National Collegiate Athletic Association (NCAA) eligibility expired and she never returned to sport.
Evaluating the Relationship Between Ballet Dancers and Incidence of Femoroacetabular Impingement
Authors: Minter Rebekah , Springer Alex , Tripp Patricia M.
Published: February 2022

Dance demands performers engage in rigorous artistic and physical movement patterns. Classical ballet dancers repeatedly perform extreme ranges of motion, which can lead to irregular stresses on the hip joints that may cause pathologies, such as femoroacetabular impingement of the cam, pincer, or mixed type. These pathologies can be detrimental in the long term to the dancing body. Is participation in classical ballet correlated to the incidence of femoroacetabular impingement? This paper will appraise the current evidence regarding hip injury incidence to identify potential factors, which may correlate with incidence of femoroacetabular impingement in ballet dancers.