bluuebunny/crossref_metadata_2025_split huggingface dataset:
Leaving-Velocity and Exhaust Loss in Steam Turbines
Authors: Robinson Ernest L. 
Published: February 2023

Abstract
This paper gives an exposition of the various items which go to make up the leaving velocity and exhaust loss of a steam turbine. The importance of this loss and the rapidity with which it increases at high loads cause it to be a determining influence in fixing the economic rating of a machine. The several elements necessary for an analysis are each evaluated in a fairly direct, although sometimes approximate, manner. More detailed and precise estimates might be made but are beyond the intent of this paper.
The loss in question occurs in the exhaust hood between the last wheel exit and the exhaust flange to the condenser. It is made up both of kinetic energy loss and of pressure loss through the hood and each effect varies with load and with location around the wheel annulus. Moisture is allowed for; supersaturation neglected.
The total loss may be expressed in Btu per pound flow to condenser or as a per cent of adiabatic heat drop or preferably as a per cent of total energy theoretically available for conversion to switchboard power.
With a particular exhaust operating at fixed steam conditions, the leaving velocity and exhaust loss increases roughly as the square of the load (parabolic rule).
With a particular exhaust passing a fixed flow, increasing the total available energy in the higher stages of the turbine by improved steam conditions correspondingly reduces the percentage loss in the exhaust (hyperbolic rule).
With a fixed percentage loss in a particular exhaust the power may be increased by improved steam conditions as the 3/2-power of the total available energy by increasing the flow to the condenser.
Base-load operation justifies more liberal exhaust areas than peak-load service but in the ultimate the heat-rate-load curve is the characteristic which is of most importance to the operator and second only to the reliability of performance.
Laws of Elastic Behavior in Metals: Summary Report on Experimental Program at Union College by A.S.M.E. Special Research Committee on Mechanical Springs
Authors: Sayre M. F. 
Published: February 2023

Abstract
To aid in rational spring design and in other problems of design where resilience or deflection are important matters, a general picture may be advisedly drawn of various phases of elastic behavior in metals, which deviates widely from the simple explanation given by Hooke’s law. For rough computation these deviations need not be considered, but where loads are high enough so that an accurate knowledge either of stresses or of deflections is required, or where an accurate theoretical knowledge is desired, they cannot be ignored. The statement given below, which in places is necessarily more or less theoretical, summarizes this picture. It emphasizes particularly those various factors which have been brought out in the work carried on at Union College for the past few years under the auspices of the A.S.M.E. Special Research Committee on Mechanical Springs. Accompanying tables give numerical values of these various effects for a range of different metals.
Plastic Behavior in the Light of Creep and Elastic Recovery Phenomena
Authors: Sayre M. F. 
Published: February 2023

Abstract
This paper briefly describes various phases of creep and elastic recovery in metals and offers a new theory of the mechanism by which these phenomena may be brought about. This explanation may also, in some measure, apply to the larger problem of plastic flow in metals in general.
No clear-cut differentiation seems to exist between the creep effects which occur below the elastic limit and the larger plastic yield occurring at higher stresses. One apparently merges gradually into the other.
The amount of creep and hysteresis seems to be definitely related to the temperature of the metal and to its state of internal stress. Any satisfactory theory of the mechanism of plastic flow must explain these facts and must also account for the elastic recovery effects, the time lag in initial creep, and the presence of continuity in metal even after slippage has extended from one crystal into a second differently oriented crystal.
The author suggests several hypotheses to explain these and his explanation seems to agree reasonably well with the facts observed from accurate measurements made at Union College, as well as with observations made by others. Various theoretical reasons also support these hypotheses.
Effect of Skewing and Pole Spacing on Magnetic Noise in Electrical Machinery
Authors: Mikina S. J. 
Published: February 2023

Abstract
The operation of rotating electrical machinery over a wide range of speeds often leads to the emission of intense magnetic hum due to resonant vibration of the machine frame at some speeds in the running range. The probability of establishing a condition of resonance at least at one machine speed is quite high due to the fact that the machine frame is capable of vibrating in a relatively large number of normal modes of vibration, any one of which may be excited under certain conditions. It is shown that in cases where the electromagnetic disturbances arise from periodic variation of magnetic reluctance between the poles and a slotted armature it is possible to reduce the resultant exciting force on a frame to zero by suitable disposition of the field poles with respect to the armature or vice versa, having regard both to the relative shapes of the poles and the slots and to the magnitude of the pole pitch.
Further Experiments on the Variation of the Maximum-Lift Coefficient With Turbulence and Reynolds’ Number
Authors: Millikan Clark B. 
Published: February 2023

Abstract
The experimental work presented in this paper represents an extension of the earlier results published by the author in conjunction with Dr. A. L. Klein. The earlier investigation dealt only with the N.A.C.A. 2412 airfoil, while the new tests employed a thick propeller section and a thickened Clark Y wing whose maximum thickness was 18 per cent of the chord. All three airfoils were also investigated with simple, split-trailing-edge flaps whose chord was 25 per cent of the wing chord and which were deflected 45 deg down from the under surface of the wing. The measurements were made at various Reynolds’ numbers and with varying degrees of turbulence produced artificially by a grid of small rods placed different distances upstream from the model.
The experimental results with the new sections tested differ in many particulars from the earlier results with the 2412 section. A qualitative explanation of these differences is given in the light of the theory of Dr. Th. von Karman and the author.
It is concluded that, although this theory is satisfactory for a certain class of airfoils, it cannot be applied to certain other less conventional types. It appears that there exists at present no satisfactory method of predicting the nature of the dependence of CLmax on Reynolds’ number and turbulence for an arbitrary airfoil section.
Manufacture of Large Seamless Steel Tubes by the Tschulenk Forge-Rolling Process
Authors: Herschmann Arthur J. , Tschulenk Leopold 
Published: February 2023

Abstract
In this paper the authors present a new technique for the manufacture of seamless steel tubes and other hollow steel bodies with diameters from 20 to 60 in. or even greater, lengths up to 60 ft., and wall thicknesses from approximately ⅝ in. up to almost any thickness that may be required. Except in very special instances such tubes or vessels would be completed from the original hollow steel block in a single pass without previous forging of the ingot and without the necessity of subsequent tooling. Both the design of the mill and the details of its operations are described, and in conclusion the authors deal briefly with the manufacturing economies which may reasonably be expected.
Air Flow in Fan-Discharge Ducts
Authors: Marks Lionel S. 
Published: February 2023

Abstract
This paper is concerned with an examination of possible causes of the discrepancies which are sometimes found between pitot-tube measurements and nozzle measurements of the volume of air flowing in a fan-discharge duct. Among the conclusions reached are the following: (1) Air pulsations may cause a small error; (2) Incorrect location of the outermost pitot-tube station results in an error of at least 0.6 per cent; (3) pitot-tube errors and non-axial flow are the principal sources of error.
This paper also gives the characteristics of various pitot tubes, shows that non-axial flow exists in the discharge from single-inlet-centrifugal and propeller-type fans and indicates that this discrepancy can be eliminated by the use of egg-crate straighteners which it recommends for adoption in standard test practise. It is indicated, too, that the present standard length of test discharge duct can be halved without loss of accuracy and the friction coefficient omitted.
It is recommended by the author, as a result of the study covered by this paper, that for test purposes the term “velocity head” should be redefined and that a more precise specification for the pitot tube should be adopted.
Ten Years of Stoker Development at Hudson Avenue
Authors: Driscoll John M. , Sperr W. H. 
Published: February 2023

Abstract
Hudson Avenue Station is a stoker-fired generating station of 770,000-kw rated capacity. The station was started in 1922 with 14-retort underfeed stokers of 355 sq ft projected grate and ashpit area and completed in 1932 with an installation of 15-retort stokers of 694 sq ft projected grate and ashpit area. Development of the rated station capacity requires that the latter installation of stokers burn coal at the rate of about 65 lb per sq ft per hr, using eastern semi-bituminous coal of about 14,000 Btu per lb as fired. On test, coal was burned at the rate of 75 lb per sq ft per hr for 48 consecutive hours, at a steam-generating-unit efficiency of 77 per cent.
The development of the various stoker units, of which there are five different types, is described and illustrated in this paper. This station was the location of the development by the Westinghouse Company of the first “link-grate” stoker, which was successfully applied here in a 15-retort design having a projected grate and ashpit area of 524 sq ft.
The 1932 installation of American Engineering Company’s Taylor stokers is equipped with manual zoned-air control, which divides the air supplied to the grate section into 69 separately controlled zones. These stokers are the longest single-ended underfeed stokers on record, measuring 26 ft 7 in. from front furnace wall to the rear of ashpit.
The various steps in the development of the underfeed stokers to obtain the desired capacities are described, and an apparent limitation in capacity of a purely underfeed stoker of any considerable length is discussed.
This paper discusses also the unburned-gas losses and the cinder losses in the heat balance of a boiler-stoker test. The cinder loss attains considerable magnitude in stoker operation at high-burning rates, and loss data are given for a number of stoker tests at coal-burning rates up to 75 lb per sq ft per hr.
The extent of improvement in efficiency in stoker operation over the period of ten years due to stoker design and associated equipment is discussed from the standpoint of the installations in this particular station, efficiency data being given in curve form for the various stoker installations.
It is the hope of the authors in presenting this paper that it will serve steam-plant designers as a basis of facts on efficiency and capacity possibilities of large stoker-fired installations in the present state of the art.
A companion paper by Messrs. Hardie and Cooper, of the Brooklyn Edison Company, entitled “The Test Performance of Hudson Avenue’s Most Recent Steam Generating Units” presents test data and describes the test procedure and methods.
Steam-Turbine Leaving Losses and Vacuum Corrections
Authors: Helander Linn 
Published: February 2023

Abstract
Based upon the discussion of steam flow through non-divergent nozzles with oblique exit faces in “Die Dampfturbinen”, by Gustav Flügel, this paper presents a procedure wherewith steam-turbine vacuum corrections may be calculated with a fair degree of accuracy when the design characteristics of the last row of blades and one set of water rates for specified steam conditions and loads are known. The procedure outlined is designed primarily for consulting engineers and power engineers, not for the turbine engineer. On that account certain simplifying assumptions have been introduced. These simplifying assumptions, although perhaps not acceptable where precise results are required, will be found satisfactory for the purposes for which the formulas presented herein have been developed. A comprehensive sample calculation is used to exemplify the procedure outlined.
In addition to a procedure for evaluating vacuum corrections, the paper presents simple formulas for evaluating small increments of isentropic heat drop when the expanding steam is saturated. These formulas give evaluations of small increments of heat drop more accurately than they can be read from ordinary steam charts and may be solved with little if any more labor than is used in reading charts.
Certain formulas are also presented which evaluate the mass rate of steam flow through a blade or nozzle when the critical velocity is reached therein, the mass rate of steam flow through a nozzle or blade when the terminal nozzle or blade pressure is the minimum attainable (that is, when the exhaust-chamber pressure is at or below that corresponding to the limiting vacuum), the rate of change of internal shaft work with a change in the exhaust-chamber vacuum temperature for expansions beyond the critical pressure, and the approximate rate of change of internal shaft work with vacuum temperature when the terminal blade pressure is above the critical pressure. Approximate formulas are given which express the specific volume and latent heat of dry saturated steam in terms of the temperature of the steam. These formulas have been developed for use where the exhaust steam is saturated and where, in addition, the temperature of the exhaust steam does not exceed approximately 140 F.
Application of the Elastic-Point Theory to Piping Stress Calculations
Authors: Spielvogel S. W. , Kameros S. 
Published: February 2023

Abstract
The application of the neutral-point theory to piping expansion problems leads to a simplification in their solution. A simple transfer formula introduced by the authors eliminates what would have been a laborious step in the computations and resolves the procedure into the determination of two moments of inertia and the product of inertia of the pipe line with respect to two rectilinear axes through its center of gravity.
Propeller Pumps
Authors: O’Brien M. P. , Folsom R. G. 
Published: February 2023

Abstract
This paper presents a simplified method of design with performance prediction throughout a reasonable portion of the operating range near the design point of propeller or axial-flow pumps. The results obtained by this method are compared with test characteristics for a known pump and very good agreement obtained. Cavitation phenomena are not considered.
The system of computations is based essentially on the propeller-blade element theory as used by Pfleiderer. The assumptions involved are clearly stated and the validity of each discussed. A theoretical proof for the desirability of constant total head being developed over the propeller disk is given. A sample computation is included which clearly illustrates the application to an actual pump.
Equally good agreement was found in computing the characteristics of a propeller fan.
Cause and Prevention of Turbine-Blade Deposits
Authors: Straub Frederick G. 
Published: February 2023

Abstract
A survey was made of power plants encountering turbine-blade deposits and it was found that this trouble results from contamination of the steam by the boiler water. A study in the laboratory showed that sodium hydroxide is the material which causes the sticking to the blades. It was also shown that when the sodium hydroxide is neutralized and changed to a salt such as sodium carbonate, it will not adhere. The presence of sufficient amounts of inert salts, such as sodium sulphate, with the sodium hydroxide also will stop the deposit from forming.
The action of sodium sulphate in preventing the blade deposits was studied in a large central power plant, and the deposit was materially reduced. A small testing unit for detecting the presence of adhering salts in the steam was developed and used in the power-plant tests.
Radiation From Nonluminous Flames
Authors: Hottel H. C. , Smith V. C. 
Published: February 2023

Abstract
Experimental results on the total radiation clue to carbon dioxide, water vapor, and mixtures of the two that were recently reported were obtained in a chromel-wound furnace, the maximum operating temperature of which was 1850 F. The final plots were obtained by extrapolating to 3600 F the experimental data covering the range from room temperature to the furnace maximum.
A method is now described for determining these properties directly in the upper temperature range. It consists of measuring the emission of radiation, and the corresponding temperature, from overventilated flames of carbon monoxide, hydrogen, and mixtures of these in a Meker burner of varying length. The products in the flame are calculated from the mixture fed to the burner.
Results are presented for flames of carbon monoxide in mixtures of oxygen and nitrogen in which the burner grid length is varied from 2 to 16 in., the theoretical oxygen from 100 to 300 per cent, and the flame temperature from 2600 to 3800 F. The results establish the validity of the carbon-dioxide radiation chart in its high-temperature range. Less extensive measurements on illuminating-gas flames establish the validity of the water-vapor radiation chart at temperatures of 2500 to 2800 F when the thickness of gas layer is small.
Effect of Concentrated Sodium Hydroxide on Boiler Steel Under Tension
Authors: Perry A. S. 
Published: February 2023

Abstract
The study reported in this paper was undertaken primarily for the purpose of developing failures in typical boiler plate under tension and in contact with high concentrations of sodium hydroxide in water solution. The failures occurring were examined carefully for evidence commonly considered indicative of caustic embrittlement. Photomicrographs are presented showing the presence of both intercrystalline and transcrystalline cracks. The author also includes a discussion of riveting pressures inasmuch as such pressures tend to affect the stresses in the fabricated unit. Impurites in the metal used for rivets and plates are also considered.
As a result of these studies it is concluded that whereas the stresses in the fabricated unit and the concentration of caustic in solution may be primary causes for the development of the phenomenon of caustic embrittlement, other factors contributing to metal stress and perfection of the fabricated unit may logically be considered in arriving at the fundamental cause of embrittlement. Typical of these factors are (a) riveting pressures, and (b) purity and uniformity of rivet and plate metal.
A more conscientious consideration of the nature of the resulting cracks in boiler failure will indicate the presence of both transcrystalline and intercrystalline cracks; and finally it is pointed out that intercrystalline cracks may not always be associated with caustic attack.
Effect of Solutions on the Endurance of Low-Carbon Steel Under Repeated Torsion at 482 F (250 C)
Authors: Schroeder W. C. , Partridge E. P. 
Published: February 2023

Abstract
The stresses to which the steel in a boiler is subjected may be divided into (a) static stresses and (b) repeated stresses. A great deal of experimental work at boiler-water temperatures has been directed toward the determination of the effect of solutions on the physical properties of the steel as measured by static tests, but repeated-stress testing under these conditions has received comparatively little attention.
In the investigation discussed in this paper, repeated torsion testing with a rather slow repetition of the stress was used to measure the comparative effect of air, water, sodium hydroxide, and other solutions on steel at 482 F.
Under the conditions investigated it was found that water caused failure more rapidly than air, and sodium hydroxide caused failure more rapidly than water. Sodium chloride and sodium sulphate in water solution had no different effect from that of water alone. Sodium carbonate and tri-sodium phosphate in water had about the same effect as sodium hydroxide. The addition of sodium carbonate in solution, or sodium sulphate as excess solid to the sodium hydroxide did not prevent the action of the sodium hydroxide in these repeated torsion tests.
It was found that by the addition of either sodium or potassium chromate, or sodium nitrate to the sodium-hydroxide solutions, the action of the sodium hydroxide could be prevented and the endurance of the specimen under the test conditions could be brought up to a value at least as high as that for water alone.
The endurance of the specimens does not appear to have been directly related to surface corrosion or pitting.
Testing of Controllable-Pitch Propellers
Authors: Lampton G. T. 
Published: February 2023

Abstract
So much has been written about the effect of controllable propellers on airplane performance that aeronautical engineers now are probably more interested than ever before in the general engineering background of this device which permits them to use wing loadings upward of 20 lb per sq ft. The problem involved in changing the pitch angle of blades subjected to centrifugal loads of the order of 50 tons with safety and reasonable weight limits is obviously one which requires a competent design and testing staff equipped with elaborate facilities. The purpose of this paper is to describe some unique test methods and equipment which have been used successfully both in the development and in the testing of the Lycoming-Smith propeller.
The Accuracy of the Cleanliness-Factor Measurement for Surface Condensers
Authors: Hardie P. H. , Cooper W. S. 
Published: February 2023

Abstract
The authors outlined in a previous paper an experimental method for evaluating the performance of steam condensers in terms of a new quantity which was defined as the “cleanliness factor.” The method of determining the cleanliness factor is essentially a sampling process, involving the measurement of the performance of a limited number of new and old isolated tubes.
The present paper is concerned chiefly with the accuracy of this determination. The investigation reported herein was conducted for the specific purpose of determining whether the limited number of test tubes (24) heretofore used is sufficient to indicate adequately the cleanliness factor of an entire condenser. By the use of 96 isolated test tubes, data were obtained to compute the probable accuracy for any number of isolated tubes. The probable accuracy was found to be 98.4 per cent for 24 tubes, and 99.2 per cent for 96 tubes.
Theory and Practice of Wire-Line Coring in Hard Formations
Authors: Klep John P. 
Published: February 2023

Abstract
The author discusses the difficulties encountered in drilling oil wells through hard rock to deep horizons and the necessity for more accurate correlations. He points out the conditions for the successful correlation by geophysical, electrical-resistivity, and microscopical examinations of well cuttings and discusses the necessity of coring to establish absolute characteristics of sediments, exact correlations, and true value of formations. The principles and theory of wire-line coring are presented by the author together with a discussion of the applications of the various known devices. He also compares wire-line coring with other methods. Reference is made to the introduction of wire-line coring in hard-formation territory, to the difficulties encountered, and to the development of processes used to overcome these difficulties.