bluuebunny/crossref_metadata_2025_split huggingface dataset:
Summary 1: The Influence of Engine Component Inertia Forces on Minimum Oil Film Thickness in Connecting Rod Big-End Bearings
Authors: Booker J. F. , Martin F. A. 
Published: June 2010

when Designing steadily loaded bearings the designer can usually predict the position of the journal centre quite easily with the aid of one of the many load carrying capacity/eccentricity relationships available. With dynamically loaded bearings, however, the journal path will vary in magnitude and direction throughout the loading cycle and one of the designer's interests is in the trends of maximum eccentricity ratio and the corresponding oil film thickness for various bearing and engine conditions. From experience with journal path predictions for big-end bearings it has been found that the eccentricity ratio in the bearing due to the peak firing load seldom exceeds that obtained by the inertia load loop (although this load is smaller) and therefore, as a first approximation, it is thought justifiable to neglect the gas forces. The results of this inertia study (numerical solution) applied to big-end bearings are presented in a general graphical form. Further work can be carried out on the same basis for main bearings, but this is more difficult to present in a general fashion as there are many more variables to consider, such as the phasing and magnitude of the crank out of balance and the firing order. This report therefore concentrates on the first step, i.e. that of big-end bearings.
Paper 7: The Protection of Car Occupants in Accidents
Authors: Grime G. , Lister R. D. 
Published: June 2010

This paper is concerned with the main principles which should govern the design of devices to protect the occupants of cars in accidents and includes consideration of desirable alterations in the design of the car. The main conclusion is that effective protection can be obtained at very little extra cost by means of properly designed seat belts, and that major alterations to the design of the car are necessary in only a few instances.
Paper 2: Signalling and Telecommunications Works on the Euston Main Line Electrification
Authors: Brentnall E. G. 
Published: June 2010

The basic requirements of the signalling and telecommunications scheme are presented in this paper. Details of maximum speed of various types of trains, average headway, desirability for consistency of aspects, all necessitated the provision of four-aspect colour-light signalling with continuous track circuiting. Originally, power signal boxes with limited range were programmed, but economic conditions necessitated reconsideration for some electromechanical boxes. Difficulties arising in the manning of the signal boxes later caused replanning for power signal boxes throughout with much longer sections controlled from each box following technical developments. Particulars are given of the telecommunications requirements in principle. The planning of the signalling and telecommunications schemes are dealt with in some detail with special reference to the various factors to be met. Sections of the paper deal with design factors and equipment both for signalling and telecommunications with special reference to the methods which had to be adopted to give immunization against inductive effects from the 25 000 V 50 c/s traction system. Particular reference is also made to the instances where other electrical factors had to be met. Developments which occurred during the progress of the scheme are detailed and their effect on the original design is mentioned. The planning and execution of the installation work and the testing and commissioning are described, with some reference to the maintenance of the works. At the end of the paper reference is made to present-day experiences and some remarks are presented about the future.
Paper 12: The Mechanical Design of Fuel Injection Equipment
Authors: Warwicker P. G. , Cornfoot P. F. 
Published: June 2010

Loading problems on cam, follower, pump, and tappet are frequently encountered in high-output engines. The main parameters are Hertzian stresses, bouncing tendencies, and cam profile design. Rising speeds, line pressures, and injection rates have brought about major changes in pumping element design, and in this paper plunger and sleeve materials and their failures are discussed. Hydraulic considerations determine the fuel pump delivery valve design, and the chief mechanical problem is fatigue failure. Body redesign has accommodated the increased clamping and sealing loads which higher line pressures demand. Causes and prevention of fuel pipe breakage are described. In the injector assembly the major mechanical problems are the inertia of moving parts, spring stresses, and sealing. As regards future designs, are there ultimate hydraulic or mechanical limitations to conventional jerk pumps and, if so, what are the alternatives ?
Paper 25: Use of Similarity Numbers in Connection with Plain Bearings under Conditions of Varying Temperature and Viscosity
Authors: Pollmann E. 
Published: June 2010

The similarity conditions for the phenomena in a lubricating film follow from the Reynolds equation and from the energy equation. It will be shown that with the aid of some justifiable simplifications the properties of a bearing may be described by two characteristic magnitudes only. From the inlet viscosity, a loading value and a similarly constituted temperature rise value may be derived. Further, since an approximation method is used, the calculation effort has been considerably reduced. (A similar form of approximation was used by Schiebel and Vogelpohl for the finite bearing.) The results obtained for a 360° bearing are compared with those obtained by Motosh, which were calculated from a more complicated numerical method. As an example of the description of the bearing characteristics, calculations are made for a 120° bearing, and the temperature and pressure curves together with the loading and temperature rise values are shown in the form of curves. The limitations on the use of adiabatic conditions are illustrated by an example. Finally, the effects arising from the variation of viscosity with pressure are demonstrated by means of a further example. In the application of the method, it is not necessary to calculate with a mean value of viscosity for the lubricating medium in the lubricating gap, so that more reliable calculations are possible.
Paper 31: Lubrication and Wear Fundamentals for High-Vacuum Applications
Authors: Johnson R. L. , Buckley D. H. 
Published: June 2010

The problems of lubrication and wear in vacuum are mostly caused by the low pressure and the lack of oxygen. Important considerations are: (1) inability to maintain oxide films; (2) evaporation of lubricants and (3) poor heat transfer. The usefulness of the adhesion concept of friction is demonstrated by correlation of cleavage and adhesion studies with sliding friction. Behaviour of solids in these areas of study is significantly influenced by crystal structure and atomic bonding forces. Better definition of surface, lubricating films and slider material on the basis of atomic arrangement in crystals and molecules is required for continued progress. Metals and alloys with hexagonal crystal structure and a c/a stacking ratio approaching ideal (1·633) have useful friction and wear properties. Crystal structures of inorganic lubricants are also important. Adhesion between surfaces in sliding contact may result in junctions formed from (1) diffusion bonding (i.e. solid solubility), (2) chemical bonding and (3) mechanical bonding. Material transfer occurs during sliding with most material combinations by one or more of these adhesion processes. Properties such as the proper hexagonal structure or contamination films that cause subsequent shearing to occur in the plane and region of the original interface will minimize adhesive wear. Friction responds to factors such as crystal structure that influence the shear strength of metal junctions. Methods for maintaining useful surface contamination and obtaining proper crystalline structure are the most promising areas for study in achieving efficient operation of sliding surfaces in vacuum. The problems as well as materials for their solutions need to be defined on the basis of atomic structure.
Paper 21: Use of Grease in Rolling Bearings
Authors: Scarlett N. A. 
Published: June 2010

Lubricating greases are semi-fluid or solid lubricants consisting of a thickening agent in a liquid lubricant. They differ from conventional lubricating oils in that they are non-Newtonian in behaviour and will not flow unless stressed under shear beyond a certain value, known as the yield value. It is this ‘non-flowing’ characteristic of greases that enables them to offer certain advantages over lubricating oils and results in their extensive use for the lubrication of rolling contact bearings. This paper outlines the uses and limitations of grease lubrication in rolling bearings. In particular, factors that can influence performance, such as bearing design, speed and temperature, are dealt with in some detail. In addition, new lubrication problems encountered in atomic reactors and aerospace equipment, involving nuclear radiation and inert atmospheres, are discussed, together with steps taken to solve the problems. In conclusion, the paper outlines observations made on the mechanism by which a grease lubricates and also suggests possible future trends in grease development which will be required to cater for the more exacting operating conditions demanded by modern machinery.
Paper 1: Natural Convection in the Supercritical Region
Authors: Parker J. D. , Mullin T. E. 
Published: June 2010

In the region just above the thermodynamic critical point, the thermodynamic properties vary rapidly with small changes in temperature. The rapid variation of the physical properties exerts a strong influence on the natural convection heat transfer process. Relatively large heat transfer coefficients are experienced in this region. Consideration of the fundamental equations involving conservation of mass momentum and energy has led to the establishment of a set of significant parameters to be considered in this problem. The derivation is essentially an extension of the work of Sparrow and Gregg (I) and is more adaptable to actual solution of the general variable property problem. The technique allows for variation in density, specific heat, viscosity, and thermal conductivity. An important step in the development is the use of thermodynamic relationships to obtain derivatives of properties with respect to temperature. A demonstration of the technique is made for Freon 114 using a Martin (2) equation of state along with Sutherland and Bromley equations for viscosity and thermal conductivity, corrected for pressure (3) (4). The use of a reference temperature in the variable property problem is critically discussed.
Paper 10: Experience with Aluminium Alloys for Exterior Trim
Authors: Bigford H. M. , Thomas R. W. 
Published: June 2010

One sphere in which corrosion has presented little or no problem is that of bright anodized exterior trim on motor vehicles. A brief survey is made in this paper of the principal aluminium alloys used for this purpose, the nature of the anodizing process, and methods used for quality control. The excellent service performance is a result of the use of high-purity materials coupled with the extreme care and cleanliness required at all stages of production and fabrication to produce materials of anodizing quality. Reference is also made to maintenance, design, fixing, and painting of anodized trim.
Paper 1: Skidding of Vehicles Due to Locked Wheels
Authors: Koiter W. T. , Pacejka H. B. 
Published: June 2010

The present paper combines older work by the first author with more recent research by the second author. A basic simplifying assumption of the entire investigation is that the height of the centre of gravity of the vehicle above the road surface has been neglected, such that the vertical wheel reactions remain constant. In the earlier analysis it was also assumed that the drift angle of rolling wheels under lateral forces may be neglected, and the possibility of lateral skidding of rolling wheels was also ignored. The equations of motion may then be reduced to a comparatively simple non-linear second-order system of ordinary differential equations. The equations may be given a non-dimensional form in several ways, and two such methods are employed to reveal some characteristic properties of the skidding phenomenon. The more recent analysis has been refined considerably by proper allowance for the drift angle of rolling wheels under the action of lateral forces, for the possibility of sideways skidding of rolling wheels, and for braking action on the rolling wheels. The equations of motion then reduce to a third-order system which may be solved in closed form in the linear case of small deviations from a rectilinear motion. It appears that the drift angle of rolling wheels under the action of lateral forces leads to a small increase of the critical speed and to a significant reduction of the danger when the critical speed is exceeded. The non-linear equations for larger deviations from a rectilinear motion cannot so easily be discussed qualitatively, but detailed results have been obtained by means of a digital computer.
Paper 5: Vehicle Behaviour in Combined Cornering and Braking
Authors: Harris A. J. , Riley B. S. 
Published: June 2010

This paper considers first the steady-state motions of a simple two-wheeled vehicle model having non-linear sideway force relationships with respect to tyre slip angle. It is shown that any steady-state conditions may be represented and their solutions found by simple graphical means, using only the non-linear curves. The curves can be modified to take into account the influence of vehicle parameters such as compliance, roll steer, wheel camber, and load transfer. Stability boundaries are discussed and criteria are presented showing that stability of the motion depends only on the slopes of the curves and the speed of the manoeuvre at the cornering acceleration being considered. A more involved four-wheeled vehicle model is then considered when subjected to braking while cornering on a fixed radius path of 45·8 m on a wet Bridport macadam surface. Actual sideway force–slip angle curves for combined braking and cornering, as presented by Holmes and Stone (see reference (6))†, are used with the equations of motion derived for the quasi-steady state conditions of decelerating while cornering. The effects of front wheel steered angle and body slip angle on the forces necessary for the manoeuvre are also considered. An envelope of maximum cornering acceleration at various braking decelerations is presented. This shows that for those particular conditions up to about 70 per cent of maximum deceleration may be obtained before there is more than about 10 per cent loss in maximum cornering ability. Outside the envelope the vehicle fails to maintain the path. At the lower deceleration the car spins, and at higher values it continues tangentially to its original path without spinning. It is also shown that the total sideway force–slip angle curve for a pair of front or rear wheels, when one or both wheels have a high braking force coefficient, can have a sharp peak, such that for small increase in slip angle there is a rapid fall in sideway force. It is suggested that this is why a rear wheel skid which occurs while braking and cornering is more difficult to correct than one which occurs when only cornering.
Paper 8: Tribology of Stainless Steel in Sodium Liquid and Vapour
Authors: Todd M. J. , Garnham A. L. , Turner S. 
Published: June 2010

Austenitic stainless steels find widespread use in sodium-cooled reactor systems because of their low corrosion rates and adequate strength. These steels are usually associated with severe galling wear and high unsteady friction when in contact in the absence of conventional lubrication. Experimental work in liquid sodium and in sodium vapour has shown clearly, however, the existence of mild wear processes in which the surface damage is slight and the friction relatively smooth. This type of wear persists for a greater sliding distance in sodium vapour than in sodium liquid at low temperature. Boundary lubrication by complex oxides is shown to be the likely cause of the mild wear, and the effects of changes of oxygen level in the liquid sodium are reported. A tentative explanation of the friction and wear behaviour is given, based on thermodynamic data.
Calculation of the Effect of the Compressibility of Grease on the Performance of a Twin-Line Dispensing System
Authors: Hutton J. F. 
Published: June 2010

The compressibility of a grease can affect in two ways the time required for the operation of a twin-line dispensing system. First, during the application of pump pressure to one of the two main pipes of the system, time is taken to compress grease into the pipe in addition to that taken to supply grease to the bearings along the pipe. Secondly, during the next cycle, when that pipe is opened to the atmosphere and the other one is being pressurized, time is required for the compressed grease to flow back into the reservoir and thus for the pressure in the pipe to fall to a value sufficiently low to allow the dispensing valves to operate. Formulae are given for calculating these time factors, and for typical modern practice times of about 2 or 3 min are obtained. This explains the observation that some twin-line systems cannot be successfully operated on cycle times as short as 3 min. The formulae may be useful in the design of twin-line systems.
Paper 14: Numerical Solutions of Flows behind Shock Waves in Non-Uniform Regions
Authors: Gururaja J. , Deckker B. E. L. 
Published: June 2010

Different computational schemes for the calculation of multi-dimensional non-stationary problems of gas dynamics with shock waves present are reviewed. A differencing scheme developed in the last few years at the Los Alamos Scientific Laboratory, known as the ‘fluid-in-cell’ method, has been employed to obtain numerical solutions for the time-dependent two-dimensional flows initiated by the passage of a shock wave in a duct with either a gradual or sudden change in cross-section and in a branched duct. The numerical results have been displayed in the form of contours of density, pressure, and internal energy. The main features of the computed solutions have been compared with the experimental flow patterns obtained by the authors. Comparison of pressure–time records shows good agreement. The fluid-in-cell method is well suited for machine calculation on a high-speed electronic computer and can treat unsteady two-dimensional compressible flow problems involving a single material within closed boundaries, without excessive demands on storage and computing time.
Paper 10: Measurement of an Average Size and Number of Droplets during Spontaneous Condensation of Supersaturated Steam
Authors: Petr V. 
Published: June 2010

This paper presents the results of measurements to determine the average size and number of droplets which appear during spontaneous condensation of expanding undercooled steam. The measurements were carried out in a non-symmetric convergent–divergent nozzle for three expansion rates, , of 2000, 5000, and 8000 units per second, and pressure in the Wilson region of 0·4–1·5 bar. The method is based on the measurement of monochromatic light beam intensity attenuation when passing through a layer of wet steam of length l (width of the nozzle) and static pressure variation through the nozzle axis. The photometric method was verified by measuring the droplet sizes in sulphur emulsion. The average size and number of droplets during spontaneous condensation were found to be dependent on the expansion rate and pressure in the Wilson region, and the results of the measurement are in qualitative agreement with those obtained by Gyarmathy. The average droplet size measured by the photometric method is about 25–60 per cent greater than the corresponding values of Gyarmathy. The droplet size measuring error, determined by an approximate analysis, was found to be in the range 15–30 per cent.
Paper 23: The Collision of Drops with Dry and Wet Surfaces in an Air Atmosphere
Authors: Parker G. J. , Bruen E. 
Published: June 2010

This paper describes an investigation into the behaviour of drops which impinge upon dry and wet surfaces. This is of particular interest in the context of the wet steam turbine. Two approaches have been made in the studies; these are: (1) Drops were made to impinge normally on to various types of dry, stationary surfaces. The drops were in the size range 300–1500 μm diameter with velocities of 2–9 m/s. (2) Drops were made to impinge on to surfaces moving with considerable velocity at right angles to the motion of the drop. Surface velocities ranged up to 45 m/s. The latter study is of direct interest for the splashing of drops on turbine casings at small glancing angles, as occurs near drainage belts. Analysis of the mechanisms involved is made from the records of high-speed ciné photography.
Investigation of Local Mixture Strength and Flame Propagation with Aided and Unaided Ignition
Authors: Lange K. , Spindler W. 
Published: June 2010

The investigation of the mixture formation and combustion in internal-combustion engines with aided and unaided ignition is of great interest in relation to the diesel engine and the hybrid engine. Cold starting, mean effective pressure, and smoke are influenced by mixture strength and other parameters. Additional problems arise with film vaporization from the combustion-chamber wall. High-speed photography, spectral analysis, pressure measurements, and gas analysis are some of the methods used to investigate the process of mixture formation and combustion. Using these methods, the mixture distribution, ignition, and flame propagation are investigated for aided and unaided ignition. Part of this experimental work was carried out by K. Feierlein and A. Held.
Paper 12: Determination of the ‘Hot Spot’ Temperature Rise from P.V.C. Insulation Characteristics
Authors: Twaites S. W. , Murray R. F. 
Published: June 2010

It is normal practice when designing electrical machines to design for operation within the maximum temperature limits of the insulation. If part of the winding is not effectively cooled under these conditions, the resulting temperature rise can damage the insulation and seriously reduce the length of operational service of the machine. This paper discusses a method of detecting high-temperature regions within a winding and of estimating the ‘hot spot’ temperature. The investigation has been concentrated on the design associated with a direct water-cooled winding, although the results could be applied generally on other electrical machines.
Paper 19: Comparison of Performance of Compensated and Uncompensated Externally Pressurized Short Multi-Grooved Journal Bearings
Authors: Chen N. N. S. 
Published: June 2010

It is generally accepted that the performance of compensated externally pressurized journal bearings is superior to ordinary journal bearings. This paper presents the experimental results of performance studies of compensated and uncompensated journal bearings under static and alternating loading with an operating frequency of 327 c/min. The length/diameter ratio of the test bearings was 1/3 and both bearings had 10 closed-end grooves machined in the bearing surfaces. Film pressure surveys reveal considerable differences in the film pressure distribution in the two bearings, and explain the difference in the performance characteristics of these bearings. Comparisons are made in terms of measured load capacity, stiffness, and lubricant flow rates. The relative costs of manufacture and the operating costs of these bearings are also discussed.