bluuebunny/crossref_metadata_2025 huggingface dataset:
Paper 32: Errors in the Measurement of Surface Temperature Caused by Perturbations of the Heat Flux
Authors: Walker V. , Rapier A. C.
Published: June 2010

The work reported in this paper was done in connection with heat transfer experiments on reactor fuel elements. Tubes in which heat was generated by an electric current were cooled on the outside by a gas flow. To avoid disturbing the flow, taking the thermocouple leads through a steep temperature gradient and exposing them to gas forces, the thermocouples were secured in holes in the tube walls and led away inside the tubes. An insert of a different material in the tube wall disturbs the uniformity of electrical heat generation. The paper presents a theoretical solution for the disturbed heat generation pattern, and that is followed by a derivation of the temperature distribution allowing for conduction in the tube and insert. Experiments were made with thermocouples secured by braze and by a copper oxide cement. The temperature disturbance was found to be unacceptable with the cement owing to its poor thermal conductivity. With the brazed attachment the disturbance was fairly small but a second source of error is pick-up by the thermocouples of the tube potential gradient. Methods of reducing pick-up are discussed.
Paper 17: Flow-Induced Vibration and Noise with Particular Reference to Heat Exchanger Tube Systems
Authors: Dye R. C. F.
Published: June 2010

The general problem of vibration of structural elements or system components produced by fluid flow has become of increasing importance in recent years. The large number of mechanisms capable of producing vibration are discussed in detail in this paper. The vortex shedding, galloping and buffeting vibrations of structures are covered and flutter is briefly mentioned. The complex vibration modes produced by vortex shedding in tube systems of cross-flow type heat exchangers are described in detail and the production of noise by resonance with acoustic standing wave frequencies of the heat exchanger vessel is also covered. The jet-switch mechanism which can lead to streamwise vibration of heat exchanger tubes is described. The useful results which can be derived from mathematical work concerning vortex streets are mentioned. The prediction of flow-induced vibration is discussed, the difficulties involved are mentioned and the frequent necessity of model testing is stressed. Finally, the simple methods by which flow-induced vibration may frequently be suppressed are described.
Paper 20: Measurement of Sliding Friction and Wear in High-Temperature High-Pressure Water Environments
Authors: Roberts W. H.
Published: June 2010

A new apparatus is described which enables continuous measurement to be made of the friction coefficient between surfaces sliding under boundary lubrication conditions in high-pressure (2700 lb/in2), high-temperature (up to 350°C) water environments.

One specimen is held stationary under load against a moving specimen which may be either continuously rotated or reciprocated, linear rubbing speeds being low (of the order of a few centimetres per second). The design of the test section is such that any one of three geometrical configurations of specimen can be selected: piston-cylinder, journal-sleeve, or crossed-cylinders. The friction force transducers which have been developed for this work are described.

Friction and wear results are presented for stainless steel (En 58E) sliding against itself, Inconel X, Nimonic 80A, chromium-plate and Deloro SF40, in the temperature range 20°-325°C.
Paper 1: The Hydrodynamics of Flat Contacts: Friction Studies in the Pin and Disc Machine
Authors: Robertson W. G. , Spillman D. T.
Published: June 2010

The friction of run-in flat steel specimens lubricated with plain mineral oils has been measured in a pin and disc machine over a wide range of operating conditions. The hydrodynamic region was identified with the aid of electrical contact measurements and the corresponding friction data were considered in terms of the various theories which have been proposed to explain hydrodynamic action in nominally flat sliding contacts. It was concluded that the Lewicki inflow, the surface roughness, and the viscosity-density wedge mechanisms could not explain the observed friction; but that it could be explained if the surfaces formed a wedge whose angle was constant over the whole range of operating conditions. It is suggested that the wedge may be formed during the running-in process by mechanical effects such as flexural distortion.

Particularly striking is the strength of the hydrodynamics which can occur in such ‘flat’ contacts: in terms of the wedge analysis the contact was operating close to the maximum theoretical load-carrying capacity.

The implications with respect to the use of the pin and disc machine as a test rig are discussed and it is suggested that there might be a practical application in the design of ‘self-adjusting‘ slider bearings.
Paper 12: A Comparison of Performance Predictions for Steadily Loaded Journal Bearings
Authors: Smalley A. J. , Lloyd T. , Horsnell R. , McCallion H.
Published: June 2010

Various predictions of the performance of steadily loaded circular journal bearings, running in the laminar regime, are compared. The values of load, friction, peak pressure, and oil flow given result from the iterative numerical solution of the Reynolds equation subject to a number of different boundary conditions, which attempt to allow for oil-film disruption. The boundary conditions considered are:

(1) That only the positive pressure region of the 360-degree full-film solution contributes to load carrying. (2) That the full-film is bounded, both at breakdown and at build-up, by the conditions that pressure and pressure derivative are zero. (3) That the pressure is zero along the line of maximum film thickness, this being the assumed build-up boundary, and the breakdown occurs when the pressure and pressure derivative fall to zero. (4) That the build-up boundary arises when the flow balance, allowing for the oil feed system, indicates a full-film, breakdown occurring as in (2) and (3) above.

The influence of mesh size, convergence limit, and finite difference formulae on the accuracy of the solutions is also discussed.

Finally a comparison is made with the results from the analytical solutions due to Sommerfeld and Ocvirk, which show large errors in load and in peak pressure. This led the authors to devise a new and accurate procedure for the prediction of load and peak pressure for finite bearings using simple formulae.
Paper 8: A Graphical Method for Predicting the Performance of Circumferentially Grooved Hydrodynamic Journal Bearings under Steady Loads
Authors: Martin F. A.
Published: June 2010

This paper illustrates a procedure of bearing design which avoids the iterative process of conventional methods of determining the eccentricity ratio in a journal bearing.

The iterative process results from the need to satisfy three simultaneous equations; in the method described, the equations are graphically defined on two sheets. The transparent sheet defines the bearing data and eccentricity ratio and the opaque sheet defines the viscosity-temperature characteristics of the oil chosen. The transparent sheet is moved over the opaque sheet according to a fixed locus till a point representing the bearing data is coincident with the oil inlet conditions. The eccentricity ratio can be read directly and power loss and oil flow calculations may then be carried out in the normal manner.

Experimental results obtained from tests with circumferentially grooved bearings have been used to test the generality of the design method and also to check the assumptions relating to operating viscosities in the bearing.
Paper 16: Shaft Wear Due to the Formation of Carbonaceous Deposits in the Oil Baffles of Steam-Turbine Bearings
Authors: Evans E. M. , Hughes Miss A. , Rushton S. G.
Published: June 2010

Several cases have occurred in which heavy wear of rotor shafts has been caused by the build-up of carbonaceous deposits in the oil baffles of steam-turbine bearings. Thois problem appears to have been confined to those designs of steam turbine in which the oil baffles operated at unusually high temperatures. A bearing rig has been constructed to reproduce as closely as possible the practical conditions at which the shaft failures occurred. Heat was applied externally so that the oil baffle temperature was 280°C and the rotor shaft temperature was 260°C. The type of failure which had occurred in service was reproduced in this rig, but could not proceed to the catastrophic extent encountered in practice owing to lack of power in the rig. A mechanism of failure is proposed, together with some suggestions for avoiding failure. These suggestions include restricting baffle temperatures and redesigning the baffles to reduce the tendency to form carbonaceous deposits.
Paper 3: Noise in Hydrostatic Systems and its Suppression
Authors: Kane J. , Richmond T. D. , Robb D. N.
Published: June 2010

In this paper, the engineer is introduced to the problem of noise, its measurement, and its control in hydraulic systems. The causes of noise are outlined, and an examination is made of the design of circuits, including consideration of the suction and delivery lines, valves and components, pumps and motors and the development of acoustic filters. The development of a pump designed for quiet running is described.
Paper 1: Hydraulic Applications in Dredging
Authors: Rye J. L.
Published: June 2010

Hydraulic power transmission has been successfully applied to most forms of dredger. Suction dredgers employ hydraulics to position the suction tube, cutter dredgers have hydraulic motors fitted to the cutter drive, and bucket dredgers have hydraulic drive to the bucket chain. In addition, hydraulics is used to power winches and capstans, and to provide remote control of various valves and doors. Other common applications found in all types of vessel are hydraulic steering gear and, more recently, reversible bow propulsion gear. The advantages of hydraulic drive over comparable electric drives are numerous but operators are conservative. Greater realization of the benefits of hydraulic power transmission will result in more development and substantial economies.
Paper 6: Hydraulic Control of Valves in Tankers
Authors: Pomper Victor
Published: June 2010

The 47 800-ton vessel Altair of the Compagnie Navale des Pétroles (C.N.P.) was the first oil-tanker to be equipped with a hydraulic remote-control system of cargo valves. The vessel was delivered at the beginning of May 1959.

The opening and closing operations of the valves were controlled from a central panel which was fitted with manually operated directional control valves. The panel was located in the cargo valves' remote-control room which also housed the indispensable remote-controlled level-indicator board.

Since then the application of hydraulic remote-controlled valves has become widespread and has taken one of two forms : that of a centralized control system or that of directional control valves located on the deck.

Remote-controlled valves are either gate valves operated by a hydraulic cylinder, or butterfly valves operated by a hydraulic rotary actuator.

The application of remote-control also allowed the setting up of the ‘free-flow’ system which uses hydraulically operated bulkhead valves.

The first ‘free-flow’ oil-tanker was the Sirius of the C.N.P.; it was delivered in 1961.

At present it appears that there exists an ever-increasing trend towards automation in the loading and unloading of tanker cargoes. This is accomplished by electrically operated directional control valves, which are connected with electrically programmed systems or with electronic servo-controls.
Paper 1: The Breathing and Combustion Requirements of the Small High-Speed Diesel Engine
Authors: Broome D.
Published: June 2010

The use of small diesel engines in light highway vehicles has increased greatly in the last few years, and such engines exhibit some specialized characteristics. The performance requirements of these engines are outlined, and their dependence on the overall air consumption of the engine is emphasized. The latter is defined as the product of the breathing and combustion phases of the engine operation.

For the breathing phase, the factors controlling the volumetric efficiency arc examined and the relative importance of heating and pressure effects estimated from the results of tests on a number of engines. The scope for further improvement is discussed in relation to these two factors, and the choice of valve timing.

For the combustion phase, the requirements of the high-speed engine are listed and briefly discussed under eight headings, namely, the limiting air utilization; fuel consumption; flexibility of operation over the speed range; ease of starting; intensity of combustion noise; sensitivity to fuel quality; overall reliability; and ease of design and manufacture. The relative merits of direct and indirect injection systems for this duty are then examined with some reference to recent experimental work, and directions in which improvements are possible and desirable are indicated.

On considering techniques which are useful in chamber development, a simple method of assessing the airflow pattern within indirect chamber layouts is described and illustrated by reference to test sequences obtained on two different combustion chamber forms. Some general notes on methods of expediting firing tests of new chamber systems are given.
Paper 2: Similarity Considerations in Assessing Diesel Engine Fuel Spray Requirements
Authors: Knight B. E.
Published: June 2010

A simplified dimensional analysis has been made of the fuel-air mixing problem in diesel engines. The dimensionless variables describing the mixing pattern have been expressed in terms of the dimensionless variables describing the engine and fuel injection conditions by means of explicit equations with numerical values for the constants. A wide range of such equations has been derived and tables of numerical values are given as examples, together with examples of engine air motion calculations for comparison. A theoretical expression for fuel-spray penetration into a cross-wind has been compared with a few experimental results.

Engine smoke and specific consumption measurements have been plotted against the appropriate dimensionless variables in two instances. In both instances the response of the engine to the variables is quite different.

It is believed that the wide range of methods of engine performance data analysis outlined in this paper will make a significant contribution to progress in understanding diesel engine combustion.
Paper 3: An Experimental Study of Flow through Poppet Valves
Authors: Woods W. A. , Khan S. R.
Published: June 2010

This report gives an account of steady flow tests carried out on poppet valves. The object of the investigation was to determine the boundary conditions for exhaust and inlet valves for subsequent use in the general programme of unsteady flow research. The exhaust valve was tested with and without pipes over a much wider range of pressure ratio and valve lift than has been carried out before and the boundary conditions have been found to be independent of the pipe and also almost independent of the position of the pressure tapping in the exhaust pipe. This result is very important and it will simplify subsequent boundary curve tests. Comprehensive tests have also been performed on the inlet valve and for reverse flow through each valve.

The two usual mathematical flow models, namely, the constant pressure and the sudden enlargement, are discussed in detail and the concept of an effective area for a poppet valve is clearly explained.

The effective areas for the exhaust and inlet valves for normal and reverse flow have been computed on the basis of the constant pressure flow model. The pressure ratio has been found to have little effect on the effective areas at low valve lifts but has considerable effects at high valve lifts. The results are presented graphically on a complete set of charts. It is illustrated in Appendix 3.II that the effective area of an exhaust poppet valve may be predicted for low valve lifts.
Paper 5: The Application of Some Analytical Techniques to the Study of Turbocharging the Automotive Diesel Engine
Authors: Garratt G. , Gee D. E.
Published: June 2010

The scope of the paper is limited to a discussion of simple turbocharging (i.e. precluding multi-stage compressors or turbines, inter-cooling, etc.) and considers only four-stroke engines. On the basis of published information the constant-pressure and pulse-exhaust systems are re-examined in the light of the requirements of an automotive engine. It is concluded that the pulse system is essential for use with existing transmissions.

Methods of assessing the thermodynamic performance of the compressor-turbine-manifold system, operating on the pulse principle, are reviewed and an overall coefficient defined. Existing methods of analysing the performance of exhaust turbines when operating in a non-steady flow field are discussed and the limitations noted. A slightly modified method, based on earlier work, is presented and should prove of value for direct application to an experimental turbocharged engine. A new method for determining the energy transmission efficiency of the exhaust manifold is derived and some preliminary results from a typical automotive engine are presented.

The overall performance of a simple turbocharged engine is examined by the use of an analogue computer model and the importance of the manifold and turbine efficiencies emphasized.

It is concluded that a complete solution of the torque-speed relationship problem is unlikely to be found using simple turbocharging alone, particularly with the 50 per cent reaction radial turbines at present in almost universal use. The analogue model of a turbocharged engine is likely to prove of increasing value and be a useful adjunct to experimental work.
Paper 6: Turbocharging the Automotive Two-Stroke Cycle Engine
Authors: Tryhorn D. W.
Published: June 2010

The paper deals with the problems of turbocharging the two-stroke cycle engine. Obtaining a sufficiently rapid drop in the pressure of the cylinder contents after exhaust port opening is chiefly dependent on obtaining a high turbocharger efficiency. However, exhaust-pipe design can be very important in this process, and a system is described which permitted the use of simple turbocharging from light load to 200 lb/in2 b.m.e.p. Good starting and acceleration demanded that energy be fed into the charging system and so the normal engine-driven Roots blower was then fitted as a second stage. This spoiled the good natural match of the turbocharger and engine but it was discovered that by control of air recirculation through the Roots blower a good match could be obtained.

The work showed that the best match leads towards a constant horsepower type of engine torque curve, and this fact should be recognized for future vehicle design.

The use of two turbochargers in series offers very high outputs with good efficiency but will require a new generation of engines to withstand the high pressures and thermal loading.
Paper 14: Acoustic Detection of Cavitation
Authors: Pearsall I. S.
Published: June 2010

The onset of cavitation in a hydraulic machine can be determined visually and its effect on performance by performance tests. It would be convenient to have an alternative method that required neither transparent sections nor expensive tests.

Initial tests have been made measuring noise over a frequency range of 20 c/s-20 kc/s in one-third octave bands, on a number of pumps and turbines. An accelerometer attached to the casing was used. The tests indicated that, generally, the onset of cavitation was accompanied by a rise in the high-frequency noise, whilst the low-frequency noise increased as the cavitation developed. A maximum of cavitation noise was reached before the efficiency and load fell off. In some cases difficulty was experienced because blade cavitation was drowned by noise caused by other cavitation, such as the vortex in a Francis turbine. It also appears that the noise following the onset of cavitation is at the frequency which is used as a critical frequency in accelerated erosion tests.

Further development of techniques is required, but the initial tests are encouraging.
Paper 9: Instrumentation for the Measurement of Hydraulic Noise in Centrifugal Pumps
Authors: Wood F. J. , Corkill J.
Published: June 2010

For a programme of research into hydraulic noise generation in centrifugal pumps, it was necessary to develop special measuring equipment for use in conjunction with existing equipment designed for the measurement of air-borne and structure-borne noise.

Small hydrophones, less than 0.5 in in diameter, in which the piezo-electric sensitive element was an axially polarized lead-zirconate-titanate disc, were designed and developed. In the design, reliability, implying both mechanical and electrical stability, was considered to be more important than extreme sensitivity; ease of construction and low cost were also taken into account. The final design, in which a thin stainless steel diaphragm was used, proved very stable and reliable and has a sensitivity of over 250 mV/lb in2 into a 200 megohm load.

Commercial tape recorders, considerably modified, were used as a cheap method of recording all data on 1/4 in magnetic tape for subsequent analysis. A time-delay tape deck was also constructed for use in conjunction with a small special purpose computer to evaluate the cross-correlation function from the outputs of two hydrophones spaced a known distance apart.

Methods of hydrophone calibration were devised, and the results agreed closely with the theoretical figures derived from the piezo-electric constants of the ‘crystals’ used.

Special consideration was given to methods of automatically recording the results of one-third octave and discrete frequency analyses in forms which would provide the maximum amount of easily assimilable information.
Paper 13: Influence of the Casing on the Calculation of the Critical Speed of Multi-Stage Pumps
Authors: Domm U. , Dernedde R. , Handwerker Th.
Published: June 2010

Pump impellers and pump casings are considered as simultaneous beams coupled through the bearings, the stuffing-box and the radial clearances acting as hydrostatic bearings.

Lomakin has given a relation for the restoring forces in smooth clearances, according to which these are to be taken as springy supporting bearings the spring constants of which are proportional to the pressure. Small clearances therefore raise the critical speed.

The procedure is a method of residues in which the estimated natural frequency is varied until the residual value diminishes. In the case of multiple masses and supports the calculation necessitates the use of digital computers.

The critical speed is calculated by extending the matrix-method known from the single beam to systems of two parallel beams. Because of the analogy of the differential equations for the shaft operating with critical speed and for the transversally vibrating beams, rotation of one beam is allowed also. By special transposition matrices, single masses, spring-elastic couplings between the two beams may be considered. The coupling forces according to Lomakin, already explained above, being proportional to the product from deflection and square of speed, formally correspond to the loading of the shaft by apparent negative masses. In the case of very close clearances the critical speed may be almost completely suppressed.
Paper 12: Generation of Hydraulic Noise in Centrifugal Pumps
Authors: Simpson H. C. , Macaskill R. , Clark T. A.
Published: June 2010

The production of hydraulic noise by two types of centrifugal pumps—volute pumps and diffuser pumps—was examined to determine the effect of design and operating conditions on the level of noise generated in the pumped liquid.

Experimental work with hydrophones in the exit and entrance to the pumps showed that for both pumps, the dominant frequencies in the noise spectrum were at rotational speed and blade number times rotational speed. It was also found that the distance between cutwater and impeller tip is critical in a volute pump as far as blade frequency noise is concerned.

Analysis of the relation between the noise measured by the hydrophones and the fluctuating pressure produced by the pump and the water flow in the inlet and outlet ducts showed that the noise can be interpreted as being directly related to the unsteady flow of water issuing from the impeller.

Test results of blade frequency noise levels were correlated with a theoretical analysis for static pressure fluctuations in the pump exit and were shown to be in good agreement. A correlation of general hydraulic noise level with pump specific speed and power consumption was also developed and shown to be reliable to within +2 dB.
Paper 11: Variation of Hydraulic Pressure in Annular Space between Guide Vanes and Impeller of a Francis Turbine
Authors: Lund E.
Published: June 2010

One of the main sources of vibration in Francis turbines is thought to be pressure-wave disturbances generated from the impeller and interference impulses between impeller vanes and guide vanes.

A theory is developed which explains the occurrence of severe vibrations caused by the elasticity of the water as a resonance phenomenon between the disturbing impulses and normal modes of vibration in the space between the impeller and the guide wheel.

The wave propagation in the fluid, which is assumed to be uniform with no steady flow, is thought to satisfy the well-known sound-wave differential equation without any damping effects. The natural frequencies for one- and two-dimensional pressure-wave oscillations are calculated.

The calculations, based on prior knowledge of the velocity of sound-wave propagation, show that a simple theory of one-dimensional oscillations interpreted as rotating sound waves in the annular space is sufficient to predict critical speeds of the turbine.

Measurements carried out on a laboratory model Francis turbine for a head of 4.5 m and a capacity of about 1.0 m3/s confirmed the presence of free oscillations and indicated the occurrence of a resonance phenomenon in the annular space.
Paper 1: Damping of Pressure Pulsations from a Turbine by an Energy-Absorber in the Pipeline
Authors: Alming K.
Published: June 2010

At a Norwegian hydro-electric power plant the pressure fluctuations generated by the turbine caused disturbing vibrations and noise in the pipeline. From both field and laboratory tests it was concluded that an energy-absorber in the pipeline would be the best remedy for the trouble. A resonator, on a principle similar to the Helmholz resonator, was designed and installed and proved to be very effective. There were, however, some practical maintenance problems which had to be overcome.
An Investigation into the Performance of Dynamically Loaded Journal Bearings: Theory
Authors: Lloyd T. , Horsnell R. , McCallion H.
Published: June 2010

The main and big-end bearings in reciprocating machinery are subjected to loads varying both in magnitude and direction. At present the only guidance available to the designer of such bearings may be a comparison of bearing performance in similar engines and it is fundamental to the introduction of improved design criteria that a prediction of the journal locus, peak pressures, and oil flow be readily available for a proposed geometry and loading. In this paper a numerical method of solution of this problem, utilizing a high-speed digital computer with a large one-level store, is described. The method rests on the assumption of isothermal conditions in the oil film and on the unimportance of the inertia forces associated with the journal accelerations.

Numerical solutions of the Reynolds equation are obtained and stored for both wedge and squeeze film terms, at a number of journal eccentricities, by using an iterative method. The oil film force and the derivatives of this force with respect to both the journal centre position and its velocity are then found by summing these pressure distributions in the required proportions. At intermediate eccentricities, the required pressure distributions are obtained by interpolation before they are summed. The journal centre locus is obtained from a step-by-step solution of two simultaneous, ordinary differential equations involving the oil film data and the external load. In addition to the locus, the maximum pressure at any instant, the oil flow, and the friction work are calculated. For big-end bearings, journal rotational velocity is not constant and this is allowed for in the analysis.

The computer program described needs no input apart from the bearing geometry and operating conditions and, because of refinement of the iteration and the integration procedures, it is economic to use for routine design studies.
Paper 8: An Investigation into the Performance of Dynamically Loaded Journal Bearings: Design Study
Authors: Lloyd T. , Horsnell R. , McCallion H.
Published: June 2010

The objects of this paper are to demonstrate the use of the method described in Paper 6 and to give an indication of the effect of design parameters on the performance of a dynamically loaded bearing. An investigation into the main and big-end bearings of a diesel engine of modern design is described.

The performance of a bearing is gauged by obtaining: (a) the minimum oil film thickness, (6) the maximum pressure developed within the oil, (c) the maximum load/projected area, and ( d) the bulk oil temperature rise.

The influence of the engine design upon the big-end bearing performance for the particular engine under consideration is found by investigating the effects of the following parameters: ( a) bearing length-diameter ratio, (6) removal of centre-circumferential groove, ( c) inlet temperature, ( d) bearing clearance, and ( e) loading diagram. This last parameter is varied by changing in turn the piston mass, the connecting-rod mass, and the position of the connecting-rod centre of gravity. Finally, the effect upon the main bearing performance of various balance weight configurations is demonstrated. The usual assumption is made to obtain the main bearing loads: that loads imposed by a crank throw are equally distributed between neighbouring main bearings.

General conclusions are made regarding the relative influence of certain bearing-design parameters upon the bearing performance.
Paper 3: An Experimental Investigation of the Thermal Equilibrium of Steadily Loaded Journal Bearings
Authors: Dowson D. , Hudson J. D. , Hunter B. , March C. N.
Published: June 2010

In the optimum design of journal bearings it is important that the best possible estimate of the effective lubricant viscosity should be made. The temperature variation experienced by the lubricant is thus of con-siderable importance. Furthermore, the heat balance and the factors which influence the distribution of the heat produced by viscous dissipation are important when cooling characteristics are studied.

This paper presents a report on the first stage of an investigation into the thermal equilibrium of steadily loaded journal bearings and an experimental investigation of temperature patterns and heat balance. The main objective of this part of the investigation was to provide background information for a theoretical analysis to be presented in a subsequent paper.

The design and development of a swinging cradle type of testing machine are described, and the measure-ments of shaft torque, pressure distribution, oil flow rate, eccentricity, temperature distribution in the bush and shaft, and oil inlet and outlet temperatures have been recorded as functions of load and speed. A description of the appropriate instrumentation is also included.

The essential characteristics of the experimental results are presented in graphical form and attention is drawn to several significant factors which provide the framework for subsequent theoretical analysis.
Paper 4: Some Experimental and Theoretical Studies of Journal Bearings for Large Turbine-Generator Sets
Authors: Duffin S. , Johnson B. T.
Published: June 2010

The bearings of turbine-generator sets are designed to meet exceptional emergency conditions. On large sets the considerations lead to bearings of such size that the hydrodynamic oil films operate beyond the laminar regime. This is demonstrated by graphs of measured power losses plotted as functions of speed for 19-in and 24-in diameter bearings. The increased losses caused by operation in the non-laminar regime are economically important: the total bearing losses of a 660-MW set reduce the efficiency by 0·5 per cent.

The behaviour of bearings operating in the non-laminar regime is not fully understood, it is therefore necessary to make a study of large bearings.

A description of the test facilities and work performed on bearings by a team of engineers in a company building large turbine-generators is presented. Experimental results are detailed and discussed in relation to hydrodynamic theory and published work on the behaviour of bearings with non-laminar flow.

A new design of bearing, containing loaded pads, is described. This bearing has been devised to operate with reduced loss and to give improved control of journal movement. Test results are presented which indicate that design aims have been achieved.
Research Report 1: Experiments on the Hydrodynamic Stability of the Flow between Eccentric Rotating Cylinders
Authors: Castle P. , Mobbs F. R.
Published: June 2010

Since THE Early Work of Taylor (I)†, it has become well known that the Couette flow between an inner, rotating circular cylinder and a concentric, stationary outer cylinder becomes unstable at sufficiently high rotational speeds. The initial instability leads to the formation of a series of toroidal vortices, commonly referred to as Taylor vortices. The vortices occupy approximately square cells, and adjacent pairs are contra-rotating. When the gap d between the cylinders is small compared with the inner cylinder radius R1, the criterion for the onset on the instability is the Taylor number T = Ω1 R1 d3 / v2 where Ω1 is the rotational speed and v the kinematic viscosity of the fluid. A widely accepted critical value is Tc = 1708. Recently Coles (2) has shown the existence of a second instability consisting of travelling circumferential waves superimposed on the Taylor vortices.
Research Report 2: Water Lubricated Bearings: An Investigation into the Effects of Debris in the Water Supply
Authors: Hother-Lushington S. , Roff M. F.
Published: June 2010

Following the establishment by previous work in this department of the practicability of using water lubricated bearings for boiler feed pumps and similar applications, and of the suitability of various journal/bearing material combinations for use in water lubricated bearings running in clear water, this project was undertaken to determine the effects of debris in the lubricating water, such as might be encountered in practical applications.

A number of material combinations were subjected to a standard test-run to obtain a comparative evaluation under extreme dirty water conditions. The best material combination, which was found to be a tungsten carbide journal with a metallized carbon bearing, was then used to determine wear rates and loading limits under various conditions.

Relationships between bearing load, dirt particle size and wear rate have been established and the results lead to the recommendation that the water supply to water lubricated bearings in the boiler feed water circuit should be filtered to remove particles of debris bigger than one third of the calculated minimum film thickness, unless this latter is greater than 60 μ (about 0.0025 in), in which case filtration is unnecessary, since it has been established that very few particles greater in size than 20 μ are present in boiler feed water.
Research Report 4: A New Flow Visualization Apparatus for Studying Journal Bearing Lubrication
Authors: Heath H. H. , Midgley J. W. , Smith C. P.
Published: June 2010

Flow Visualization of the lubricant film in bearings has proved to be a powerful technique for revealing the complex nature of cavitation, a phenomenon not readily studied by other means. The method has been exploited by Cole and Hughes (I)† and others to obtain valuable information on the cavitation in journal bearings, viewing the lubricant through a glass bearing sleeve. This approach has the advantage that it is easy to apply, but it has limitations. In particular the effects of bearing deformation and of irregularities in bearing shape, e.g. mismatch of the two halves of a split bearing, are not readily simulated and the behaviour of heavily loaded bearings cannot easily be studied.
Paper 10: Measurement, Analysis, and Interpretation of Noise in the Working Fluids of Power Plants
Authors: Lawson R. , Webb J. D.
Published: June 2010

This paper is concerned with the noise fields encountered in the working fluids of power plants under three headings: measurement, analysis, and interpretation.

A brief introduction is given to the measurement techniques employed by the authors, followed by a discussion of the analysis procedures and equipment used, together with an account of the interpretation of results. The emphasis is placed on the analysis and interpretation of random data. The methods are general and may be used in other fields.
Paper 5: The Correlation between Subjective Assessments and Physical Measurements of the Vibratory Motion in a Saloon Car
Authors: Aspinall D. T. , Oliver R. J.
Published: June 2010

Panels of observers travelled short distances in three vehicles, which were identical except for suspension components. The motion experienced by the observers was varied by alterations to tyre pressures, spring rates, dampers, and types of road surface, and was measured by accelerometers and a gyro feeding a magnetictape recorder or a galvo-recorder.

Good correlation was found between subjective assessments and simplified data obtained from detailed frequency analyses of the recorded motions of the vehicles. It is shown that the average vertical acceleration passed by a 0·75-6-c/s filter as measured by an accelerometer placed between a passenger and his seat is a good measurement of how subjects react to the low-frequency ride of a vehicle. Higher frequency floor motions, measured as the average acceleration passed by a 7-50-c/s filter, also showed good correlation with subjective assessments. The average angular displacement in pitch passed by a 0·75-6-c/s filter showed some relationship with subjective assessments of pitching of the vehicles, but roll was seldom commented on by the subjects.

The simplified measurements of linear and angular motions in two relatively wide frequency bands yield useful ride quality data; the information can be obtained by the use of relatively simple and inexpensive equipment.
Paper 8: The Effects of the 1963 Weights and Measures Act on the Design of Packaging Machinery
Authors: Sillett N. E.
Published: June 2010

Schedule 4 of the Weights and Measures Act 1963 sets out definite requirements that must be met by producers of pre-packed food products. In the past, miscellaneous products, other than foods, have been retailed in packs or containers which were not required to carry an indication of amount of product by weight or volume. The Act now makes this necessary.

Schedule 4, Parts 1–12, of the Act cover the regulations applied to food products. Since it is not possible within the scope of this paper to deal with each specific part of Schedule 4, it is intended to discuss generally the sections covered by the following packaging methods:

(a) liquid filling; (b) dry goods filling.

The parts of Schedule 4 covered under ( a) will be (5) Milk and (6) Intoxicating liquor. Parts 8, 9, and 10 will be covered under ( b).

The four basic methods of liquid filling, namely vacuum, measured dosing, gravity, and pressure, will be described. Under the heading of ‘dry goods filling’, counting, volume filling, and weighing will be discussed.

The author will explain how packer and machine manufacturer have been able to comply with the regulations without extensive redesign of existing equipment, either in use or on the market. Various methods by which increased speeds may be obtained whilst the requirements of the Act are still met, will be described.
Paper 4: Integrated Process Control on the Railways
Authors: Schmitz W.
Published: June 2010

In considering the tasks of the Railways in transporting loads of every description in an opportune manner between two points by means of trains, shunting movements, and conveying operations, the strong influence, which has hitherto existed and which will also be exerted in the future, of signalling and telecommunication techniques is demonstrated. The extension of these tasks in the context of integrated data processing, in particular to include wagon depot procedure, can be effected by the accumulation of electronic data-processing devices.

In the operational area the possibilities of automating train driving (automatic locomotion) and station inspectors' duties are explained.

In addition a study of the requirements, management, and statistics in a high-capacity control area, which finds its visual expression in an electronic data pyramid, are appropriately considered.
Paper B: A Public-Transport System Using Four-Passenger Self-Routing Cars
Authors: Blake L. R.
Published: June 2010

The proposed system is an automatic-taxi, public-transport service for towns and cities, capable of 10 000 passengers per hour per track and aimed to be competitive with the private car.

Mini-sized cars are used which carry up to four adult passengers, using induction-motor drives powered from an overhead rail. The cars are driverless and route themselves at 35 mile/h to their destination with no stops at intermediate stations, though they are slowed down when changing to another line. The cars move along a light-weight totally-enclosed track of less than 7 ft diameter, which can be supported above existing roadways or buildings.

The total capital cost is of the order of λ400,000 per single-track mile and the total operational cost 1 d. to 2 d. per passenger mile. A complete system for a town of 400 000 inhabitants, involving 100 single-track miles, would cost from λ30 million to λ40 million.
Paper 5: Design Aspects of Large Marine Engines
Authors: Butler J. F. , Ørbeck F.
Published: June 2010

The paper deals with large slow-speed marine engines with a section on crankshaft stresses, including dynamic torque calculation; static bending moments owing to firing pressure, inertia, and misalignment; combined torque and bending stress; and experimental determination of stress concentration factors in the fillet radii. Other sections deal with top end bearing loading including cyclic variation, piston head stresses, deflection of bearing housings, prestressing of main bolts, frame stiffness, and stress in combustion chamber studs as a result of pressure and thermal loading.
Paper 6: Torsional Vibrations in Fuel Injection Pump Drive Systems with Special Reference to Automotive Engines
Authors: Martyn L. F. , Silcock T. M. B.
Published: June 2010

The torsional vibrations which occur on the fuel injection pump of an automotive diesel engine were investigated. Calculations and tests showed that as well as vibrations transmitted from the crankshaft, the fuel pump could vibrate at the natural frequency of the torsional system consisting of the pump and the drive coupling against an infinite mass. This was excited by harmonic torques produced by the pump.

Calculations were made to show the effect of variables on the natural frequency of the pump system including the instance when a crankshaft natural frequency coincided with a pump natural frequency. Calculations were also made of the effect of the engine harmonic torques on the pump vibrations. The results were verified by experiments.
Paper 15: A New Family of Compact Cummins Turbochargers
Authors: Neff J. J. , Weil N. A.
Published: June 2010

About four years ago Cummins Engine Company embarked on developing a family of new turbochargers, employing similar design principles which emphasize a minimization of size, weight, number of parts, and manufacturing costs, concomitant with good aerodynamic performance and outstanding reliability. The resulting series of turbochargers is characterized by an extended vaneless diffuser, asymmetrical compressor volute, a simple V-clamp tying the compressor to the turbine, as well as novel features in the bearing and bushing design of these units.

This paper describes the analytical studies, design features, and some performance aspects of this new family of turbochargers.
Paper 11: Cavitation Damage to Fuel Injection Systems and Its Prevention
Authors: Groth K.
Published: June 2010

Wear has recently been observed on the injection equipment of diesel engines and also on petrol engines with fuel injection, the causes of which are to be sought in the formation of cavities in the liquid and their collapse. The prerequisites for cavitation and subsequent aggressive implosion exist, apart from the places behind throttling points where the flow is subject to a high drop in pressure, also in those pressure pipes where underpressure waves of a high amplitude occur as a result of reflection or a sudden pressure relief.

The wear occurring in such cases is at the same time influenced by various factors which it has been possible to determine only qualitatively, such as the surface quality of the pipe walls, mechanical stresses in the material, physical properties of the liquid, etc., and may lead to functional disturbances on the nozzle and a quick bursting of the pipe.

As an example of this, the effect of cavitation aggression on a high-speed four-stroke rail-traction engine having an output per cylinder of 90 hp at 1500 rev/min is shown. It is further explained how conclusions can be drawn concerning the existence of cavitation by means of pressure diagrams, the places in the pipe system that are particularly endangered, and how this can be adequately remedied by changes in the hydraulic system.

A further example of cavitation attack by pressure waves is the heavily worn injection pipe of a high-pressure turbocharged four-stroke marine diesel engine with an output per cylinder of 550 hp at a speed of 400 rev/min. Here, the inner wall of the pipe was also destroyed quickly and, as a result, particles of material were able to get to the nozzle.

Reducing the pressure relief in the pressure pipe at the end of injection remedied the situation, without any after-drip being observed.

Finally, the paper discusses an attack on the injection pump plunger as an example of flow cavitation.
Paper 5: Basic Anatomy of Weight-Bearing Joints
Authors: MacConaill M. A.
Published: June 2010

Weight-bearing joints are dealt with as structures composed of deformable material, this concept covering the articular cartilage, the fatty pads, the endarthrodial plates of synovial joints, and the discs between the movable bones of the spinal column. Most attention is given to synovial joints and the function of the various structures found in these is explained in terms of the need for efficient streamlining of the synovial fluid.