bluuebunny/crossref_metadata_2025 huggingface dataset:
Paper 37: Thermal Instability of a Heated Element Cooled by Forced Convection
Authors: Rapier A. C.
Published: June 2010

When asymmetrical conditions exist around a heated element cooled by flow in a channel, the temperature varies round its circumference. This results in a tendency for the hottest side of the element to bow away from its nominal axis. Usually a movement in this direction reduces the heat transfer coefficient and increases the local coolant temperature on the hot side, inducing greater temperature differences around the element in addition to further movement. Under some conditions this can lead to complete instability. This problem has previously been examined for the case of an element simply supported at each end, with reference to fuel elements for nuclear reactors. A more general approach has now been made. The behaviour of two- and three-span continuous elements has been examined using a digital computer programme. The previous solution has been extended to cover any channel shape and any number of spans. Experiments with two- and three-span elements have confirmed the predictions.
Paper 3: A Review of Forced Convection Heat Transfer to Fluids at Supercritical Pressures
Authors: Hall W. B. , Jackson J. D. , Watson A.
Published: June 2010

Current interest in heat transfer to fluids near the critical point stems from developments in steam plant, nuclear reactors, and rocket motors and this paper reviews the present situation regarding forced convection.

A brief survey of existing experimental data and empirical correlations is followed by a discussion of the main semi-empirical theories that have been proposed. It is concluded that neither correlations nor theories show sufficient agreement with experiment to justify their use except in very limited circumstances. Moreover, there are discrepancies between sets of measurements made under apparently similar conditions.

In these circumstances it is clearly necessary to review the possible heat transfer mechanisms that may be important under near-critical conditions. The paper concludes with such a review, together with suggestions for future experiments.
Paper 4: Singularities in the Thermodynamic and Transport Properties of a Fluid at its Critical Point
Authors: Rowlinson J. S.
Published: June 2010

The classical description of the critical point leads to infinities in such properties as the compressibility and the heat capacity at constant pressure, Cp, as the critical point is approached along a path in the homogeneous fluid. However, this description does not require a singularity in the heat capacity at constant volume, Cv, and supposes that the Helmholtz free-energy, A, is everywhere an analytic function of volume, V, and temperature, T.

It is now clear that this description is inadequate, that Cv is infinite at the critical point and that A is a non-analytic function of V and T. The classical description must, therefore, be abandoned and it is shown that we have, in its place, a set of inequalities between the degrees of the singularities in such thermodynamic functions as Cv, compressibility, coefficient of thermal expansion along the orthobaric curve, and the curvature of the vapour pressure line. These inequalities provide powerful tests of even the best modern measurements and enable us to give a fairly complete thermodynamic description of the singularities of the critical region.

The transport properties are not so well understood. It is probable that the shear viscosity is non-singular whilst the thermal conductivity is known to be highly singular. This last singularity is probably related to the infinity in Cv.

The dimensionless functions—Rayleigh number, Prandtl number, and Grashof number—all become infinite at the critical point.
Paper 5: A Comparison of the Natural Convective Heat Transfer Performance of Three Fluids from a Horizontal Flat Surface near the Critical Point
Authors: Bramall J. W. , Daniels T. C.
Published: June 2010

One of the main problems with heat transfer research in the critical region is the lack of accurate thermodynamic and transport property data. This lack of information makes the actual heat transfer performance very difficult to correlate, whilst the extreme property variations produce other effects, which are also dependent on the heating surface geometry. Three fluids, carbon dioxide, nitrous oxide, and chlorotrifluoromethane, were therefore tested with a view to establishing whether they had similar regions of heat transfer and whether any similarity with boiling existed. The results show that in the critical region the normal convective heat transfer is augmented by a process to give results which look very like the lower portion of the normal boiling curve. Finally the authors show evidence to support the theory that there are preferential areas of heat transfer in the supercritical region.
Paper 6: Natural Convection Effect on Heat Transfer to a Turbulent Water Flow in Intensively Heated Tubes at Supercritical Pressures
Authors: Shitsman M. E.
Published: June 2010

Experimental data are presented from studies of turbulent heat transfer at high fluxes to water flowing in vertical tubes at supercritical pressures. A comparison of data for upward and downward flows indicates an effect of natural convection.
Paper 7: Typical Heat Transfer Phenomena in a Natural Circulation Supercritical Pressure Water System
Authors: Merlini C.
Published: June 2010

This paper presents a study of the natural circulation heat transfer to water flowing under supercritical pressures. Flow oscillations occurred when crossing the critical state, both from the compressed liquid region and from the supercritical vapour region. The threshold was found to correspond to the outlet film temperature, being close to the transposed critical value. Differential pressure fluctuations with frequencies of 25–60 Hz were encountered. These vibrations are generated in the heated section and propagate in the system when resonance occurs. The heat transfer data, when compared with available forced circulation correlations, showed the need for a new correlation having smaller exponents of Reynolds and Prandtl numbers. This was attributed to the power-dependence of flow rate.
Paper 9: Investigations of Motor Car Corrosion in Finland
Authors: Asanti P.
Published: June 2010

Laboratory and field tests on the corrosion of passenger cars in Finland have been carried out. The most critical corrosion points on a car body are located in closed sections. Use of anti-corrosion oil-spraying at the critical points is lowering the corrosion rate. Up to 80 per cent of all cars are treated in this way. The annual cost of this protection is approximately 1–2 per cent of the purchase price of the car.

The garaging of a car has an important influence on the corrosion rate. The important factors are the changes in temperature and the condensation of water in closed sections of the car.

The major part of this investigation is concerned with the use of inhibitors in road salts. In laboratory tests sodium hexametaphosphate shows good protection against corrosion. A higher content of phosphate inhibitor is needed in salt mixtures when sand is present on the roads than is the case with laboratory tests on clear solutions.

Sodium hexametaphosphate reacts with asphalt compounds and the resultant splash from roads makes the windscreen and other parts of the car dirty.

The correlation between the inhibitor additions and the salt mixtures was clear in laboratory tests but quite the reverse in field tests. The reason may be the slow solubility of the inhibitor and its adsorption to the sand and clay.
Paper 7: Corrosion in the Motor Vehicle Braking System
Authors: Henderson H. B.
Published: June 2010

The paper introduces the subject of corrosion in brake systems, showing possible reasons for its emergence as a major problem, and the various types of corrosion are noted. The causes and effects of corrosion, and the deterioration of brake performance which may result, are described. Methods of protection and prevention are discussed and the importance of past experience in the development of new products is stressed. It notes that accelerated test methods are essential to simulate as closely as possible actual road conditions. The paper concludes by reviewing new materials and their possible application.
Paper 4: Effect of Environment on Bearing Performance
Authors: Scott D.
Published: June 2010

The life of bearings, components which allow relative motion between members of a mechanism, is greatly dependent upon the properties of the materials of construction, but the nature of the lubricant and the environment can have a dominant effect on the incidence of failure. Lubricant contamination and degradation can be deleterious. Additives which impart or reinforce some lubricant property desirable for a specific mechanism may be detrimental to other moving mechanisms. Water in lubricant, not adequately additive fortified, may be harmful. Solid additives such as MoS2 can be beneficial if used correctly. Incompatibility with other additives may have adverse effects.

The role of material properties and surface treatments in counteracting deleterious lubricant effects is discussed. Aspects of specific environmental effects as well as failure mechanisms in general are dealt with.
Paper 1: Corrosion Inhibitors as Additives to Highway De-Icing Salts-Laboratory Tests
Authors: Bishop R. R. , Steed D. E.
Published: June 2010

Up to a million tons of rock salt are spread on the roads of England and Wales during a severe winter. It has frequently been suggested that this salt causes increased corrosion damage to motor vehicles. In North America and Scandinavia considerable interest has been shown in the use of corrosion inhibitors as additives to highway de-icing salts and at least two inhibited salts are marketed in the United States.

Use of an intermittent salt spray test in the Road Research Laboratory (R.R.L.) has shown that a 3 per cent rock salt solution is about 13 times more corrosive than urban rainwater to bare steel. Polyphosphate and chromate type inhibitors were examined under these test conditions and were found largely ineffective in reducing the corrosion rate of bare steel. However, the polyphosphate inhibitor showed a large reduction in corrosion rate of damaged painted panels finished in current motor primers and full paint systems. The work is continuing.
Paper 25: Development of Objective Methods for Judging the Quality of Ground and Polished Surfaces in Production
Authors: Westberg J.
Published: June 2010

A survey of existing gloss measuring methods is given in this paper. Relations are established between subjective gloss, surface roughness parameters, and glossmeter readings on an optical bench for several types of surfaces.
Paper 1: The Use of a Small Digital Computer in Diesel Engine Design
Authors: Cameron H. , Freeston D. H. , Picken D. J.
Published: June 2010

The use of a digital computer for thermodynamic and mechanical design calculations is now common practice in the diesel engine industry. Normally the complexity of the problems is such that a large capacity computer is necessary for the programs. At Rugby College of Engineering Technology the approach to the design has been affected by two considerations.

(1) The requirements of a post-graduate course in Diesel Engine Design which necessitates that a team of students should be taught to understand and use the calculations and complete a design within ten months.

(2) The convenience in using the College's own Elliott 803B computer rather than buying time elsewhere.

The paper will demonstrate that a series of programs which individually are short and easily understood can be employed together for the design of a complete engine.

Details are given of programs which are used for thermodynamic optimization of the design, gas flow, fuel system analysis, bearing design, thermal loading, and vibration analysis.

A discussion of a typical design is included, illustrating the part played by the computer in the overall design.
Paper 3: An Overall Approach to the Design of Small High Speed Diesel Engines Using Digital Computers
Authors: Warman E. A. , Medhurst F.
Published: June 2010

The sequence of events from surveys of competitors, products and market requirements to production is examined. Areas are highlighted where digital computer techniques can be used to improve and speed up the design of small high speed diesel engines in a highly competitive market.

One of the basic problems is that in order to meet customer installation requirements the engines must be contained within a given envelope.

Some design problems are examined in detail and sample results of computer analysis are shown. Consideration is also given to events which assist the design process, and the programming techniques which make it easier for the designer to utilize digital computers.
Paper 10: A Computer Program for Calculating the Performance of an Internal Combustion Engine Exhaust System
Authors: Benson R. S.
Published: June 2010

The paper describes the method of presenting data for a computet program, based on the method of characteristics, which calculates the pressure and temperature in the exhaust system and cylinders in two- or four-stroke engines with valves or ports. The program is arranged so that the performance of an exhaust pipe can be assessed for a number of pipe configurations.

A brief description of the theoretical background and program format is given, followed by a suggested design calculation procedure. Examples are then given of the application of the program to both two- and four-stroke supercharged engines. The results of the calculation are compared with experimental measurements.

A description of the subroutines and the organization of a calculation on the computer, together with the data order are given in two of the appendices.
Paper 11: Computing the Gas Exchange Process of Pressure Charged Internal Combustion Engines
Authors: Ryti M.
Published: June 2010

Numerous problems associated with pressure charging can only be solved numerically by analysing the gas exchange process. The extensive practical application of step by step calculations of the process has only become possible with the advent of digital computers. For fundamental investigations the data provided by quasi-steady-state calculations are quite adequate, the amount of computing time being only a fraction of that needed for calculations in which allowance is made for non-linear wave phenomena.

The Turbocharger Department of Brown Boveri utilizes a digital computer for calculations involving the gas exchange process in conjunction with its consulting activity for the benefit of customers. The program can be adapted to solve a very wide range of problems. The procedure is briefly described and possible applications discussed with reference to the following practical examples.

Optimization of valve timing. Assessment of the results from various aspects.

Performance and design for high pressure turbocharging and for high-altitude installations. Two-stage turbocharging.

Mixture control for dual-fuel and gas engines.
Paper 18: Gas Load and Thermal Stresses in Diesel Engine Pistons and Valves
Authors: Ibrahim S. M. , McCallion H.
Published: June 2010

In the field of internal combustion engines, diesel engines have the advantage of a high thermal efficiency and of operating on cheap fuels of high calorific value. To maintain these advantages brake mean effective pressures (b.m.e.p.) are continually being increased, but limitations are imposed by the cylinder head and the piston design. Usually such problems are overcome by development testing. However, these methods give little fundamental understanding of the stress distributions and how they vary under different load and temperature conditions. In this work a method for predicting pressure and steady-state thermal stresses in pistons, of different materials, for medium speed diesel engines is discussed. The pressure is applied to simulate the engine peak pressure loading and the temperature represents the time average temperature distribution in the piston under engine running conditions. The induced stresses and strains are calculated numerically.
Paper 10: Pump Scale Laws as Affected by Individual Component Losses
Authors: Sutton M.
Published: June 2010

Although many scaling laws are available for the assessment of prototype performance from tests on small-scale models, the discrepancies between them are wide and varied.

This paper considers the effect of individual components and shows that it is unlikely that any single law can be applied to pumps as well as turbines, to pumps of different specific speeds, or to pumps of the same specific speed but designed to differing philosophies.

It is proposed that more information pertaining to scaling laws can be acquired if pumps running at different speeds and in different fluids are studied.
Paper 1: Application of Friction and Wear Results Obtained on a Pin–Disc Machine to the Ring–Traveller Problem
Authors: Powell D. G. , Earles S. W. E.
Published: June 2010

An experimental study of the dependence of the coefficient of friction and rate of wear of unlubricated steel surfaces in a pin–disc configuration has suggested the use of certain parameters involving normal force, N, and sliding speed, U, in correlating the effects of surface temperature and surface condition with both friction and wear. The interpretation of these functions in terms of the parameters of the ring–traveller problem suggests that the coefficient of friction can be expressed as a function of U2 √(traveller mass/ring radius) and the traveller wear rate is directly proportional to √ (traveller mass/ring radius) providing that sliding conditions are chosen to produce a constant value of surface temperature. This last conclusion is restricted by the previous observation that beyond a certain critical temperature periodic removal of the self-generated surface films occurs. This causes a large increase in the values of both coefficient of friction and wear rate and it is suggested therefore that the ‘temperature instability’ of the surface oxide films may possibly be the prime cause of excessive yarn breakages, and overheated travellers after long periods of operation. An end-breakage criterion is proposed.

Previously published results of the friction and wear measured in ring–traveller mechanisms are re-interpreted in the light of the parameters suggested by the present work.
Paper 3: An Experimental Determination of the Temperature at Scuffing
Authors: O'Donoghue J. P. , Manton S. M. , Askwith T. C.
Published: June 2010

Since the publication of Blok's critical temperature hypothesis, much of the test data produced from research into scuffing of gears and discs has given support to the concept, whilst more fundamental work has extended the physics of lubricant breakdown. This paper outlines the development of a simple technique for direct measurement of critical temperatures and shows that the results may be used to predict scuffing loads.
Paper 7: Load Capacity, Stiffness and Flow Characteristics of a Hydrostatically Lubricated Six-Pocket Journal Bearing Supporting a Rotating Spindle
Authors: Hunt J. B. , Ahmed K. M.
Published: June 2010

This paper contains the results, plotted non-dimensionally, of extensive tests carried out on a 1–625-in diameter grinding machine spindle lubricated hydrostatically. The horizontal spindle is directly coupled to a variable-speed motor at one end and loaded vertically at the other. The spindle is not constrained to rotate at arbitrary eccentricity values, but is able to seek an equilibrium position depending upon oil flow and rotational speed. The attitude, oil film thickness, and eccentricity are measured by mutually, perpendicular capacitance probes arranged in the bearing housing.

The results indicate considerably decreasing load-carrying capacity as the rotational speed increases, because the hydrodynamic effect tends to centralize the shaft in the bearing housing, thus nullifying the hydrostatic effect. Paradoxically the same effect causes an increase in oil film stiffness as it is generally defined.

A summary of earlier work is included, notably that of Raimondi and Boyd who considered bearings of fixed eccentricity, and the paper also presents a theoretical analysis based on the pressure- and velocity-induced circumferential flow theories.
Paper 8: Comparison of Accelerated Service Simulation Laboratory Tests for Rolling Elements
Authors: Scott D. , Blackwell J.
Published: June 2010

Although the ultimate assessment of materials for rolling elements is performance in service, full-scale testing is both expensive and time-absorbing, and an accepted accelerated service-simulation laboratory test to screen potentially suitable materials would be desirable.

Using reference materials of known service performance, results obtained from the National Engineering Laboratory rolling four-ball test, a high-speed rolling four-ball test, and the washer-type Unisteel fatigue machine have been compared. Variables in the different test methods which may influence the results are discussed.
Paper 11: Capacitance Measurements and Oil Film Thickness in a Large-Radius Disc and Ring Machine
Authors: Astridge D. G. , Longfield M. D.
Published: June 2010

This paper describes a large-radius disc and ring machine which was designed and built by A.E.I. and loaned to the Department of Mechanical Engineering in the University of Leeds. The machine was designed for the purpose of investigating the characteristics of oil films in nominal point contacts where rolling and sliding may be present.

Preliminary results are presented for the inter-specimen capacitance for various running conditions. Some of the difficulties encountered in the interpretation of capacitance measurements for a machine of this type are described. Various ways of interpreting the results are explored.

A method of dealing with capacitance measurements is described, which leads to a satisfactory agreement with theoretical predictions.
Paper 20: Stability of Self-Generated Oxide Films on Unlubricated En 1A Steel Surfaces
Authors: Earles S. W. E. , Powell D. G.
Published: June 2010

Previous work has shown that within the range 20 < N1/2 U < 600 lbf1,2ft/s friction and wear between unlubricated En 1A steel surfaces is determined primarily by the condition of self-generated oxide films. The stability of these films has been examined using a contact resistance technique and metallurgical examination. At a sliding velocity of 100 ft/s, periodic changes have been observed to occur in the contact resistance between the surfaces. During a cycle the contact resistance increases rapidly at first and then more gradually until a critical value is attained when the film disintegrates. Simultaneous with the surface breakdown there is an increase in the coefficient of friction, pin wear rate, and bulk surface temperature. Conditions are such that rapid re-oxidation occurs, resulting in the formation of a new film

A metallurgical examination has shown that even using pin specimens of cold-drawn low carbon steel, subsurface grain re-orientation can be responsible for pearlite-rich layers in the stratified structure produced; hence the hardenability of the substrate, and therefore the support provided for the oxide film, can undergo significant changes as wear proceeds.

It is concluded that the unstable nature of self-generated oxide films on steel surfaces is responsible for the periodic increases in friction and wear which have been observed.
Paper 9: Thoughts on Vehicle and Road Design for Safety
Authors: Austin W. T. F. , Nash H. E. C.
Published: June 2010

Modern roads and vehicles are unlikely to be the cause of accidents when properly used. The outstanding problem remaining to be solved is that of spray. But not all roads are modern and the limiting factor in modernization is cost. Costs are given for some safety features of roads. The soporific effect of modern motorways is discussed, as is the problem of obstructions caused by roadworks and broken-down vehicles. Vehicles which may have left the road may be protected by wide verges, guard rails or by ‘break-away’ type lamp standards. Electronic aids to vehicle control are next discussed. The simplest are the flashing amber warning lights. These can be made more effective by a ‘step down’ procedure which indicates suitable rates of speed reduction when approaching a hazard, and can be backed up by a television surveillance system. The next development is to control these warning systems by means of vehicle detectors buried in the road, coupled to a computer. From this follows the principle of providing audible or visible indicators in the car itself. Next, these can be used automatically to control the speed and steering of the vehicle, which brings us to the ‘automatic driver’ which could be switched on when entering a motorway, and returned to manual control when leaving it.

A police traffic superintendent was heard to say that the defect which caused practically every accident was in ‘the nut which holds the wheel’. A patrol-car driver of his expressed the same thought differently, attributing most accidents to ‘traffic thrombosis’—a clot behind the wheel. Both were definite in their opinions, based on long experience, that modern roads and vehicles are very unlikely to be the cause of accidents when properly used.
Paper 1: Design and Development of a New Range of High-Powered Quick-Running Light-Weight Diesel Engines
Authors: Groth K. , Syassen O.
Published: June 2010

The basic desiderata which led to the development of the first series of very compact high-speed high-output diesel engines of V design developing 1400−1000 hp (metric) and having 8, 12 and 16 cylinders with ‘square’ cylinder dimensions are mentioned and the results obtained. Stroke and bore are 230 mm, the rated speed is 1500 rev/min. These engines are intended mainly for rail traction purposes but also for marine plants and generating sets, etc. Special importance was devoted in design work to the provision of a simple structure and maintenance, with a small requirement of special tools. The engine is the one with the largest single-cylinder swept volume and the highest UIC cylinder output of all 1500-rev/min engines existing today.
Paper 3: Development of the Napier Deltic Charge Cooled Engine
Authors: Taylor R. P. , Davison C. H.
Published: June 2010

This third generation of Deltic engine, of higher horsepower, is basically similar in design to the earlier units but a redesigned turbo-blower of increased efficiency has been introduced and charge-air coolers are interposed between the blower and cylinder blocks, thus enabling a greater mass of air to be trapped at a lower temperature with the charge pressure remaining unchanged. By this arrangement the power of the engine, for fast patrol boat application, has been increased to 3700 b.h.p. from 3100 b.h.p. at 2100 crankshaft rev/min.

The engine is generally of light alloy construction and for marine use includes an integral ahead and astern gearbox.

The paper gives a survey of the design changes made to the engine and the development problems encountered before a 1000-hour endurance test was satisfactorily completed.
Paper 7: Development of the Owen Organization's B.R.M. H-16 Formula I Racing Engine
Authors: Rudd A. C.
Published: June 2010

The paper sets out to show why B.R.M. selected the H-16 layout, the parts and techniques it inherited from earlier B.R.M. engines. The reasons for the various design features are given, such as casting the cylinder heads in pairs, and isolating the output gears from the crankshafts.

The problems encountered during development, including the need to change the engine's characteristics to suit those of the car, are described. The author concludes that the engine in its original form was far too heavy, that its original troubles were mainly due to over-cautiousness in trying to design out possible faults. The more advanced features gave no trouble.
Paper 2: Holographic Techniques in Engineering Metrology
Authors: Ennos A. E.
Published: June 2010

Holography is a novel method of photography using coherent light from a laser source. Its unique feature is that it records a faithful three-dimensional image of the object. This allows one to compare the shape of an engineering component at one moment in time with its shape after some change has taken place, e.g. by deforming it under load. In some cases the holographic image of a ‘master’ component can be used as a template against which similar components can be matched with high precision.

The techniques of holography, the interpretation of the results obtained, and the present limitations of the method will be discussed.
Paper 4: Lasers in the Determination of Form Errors in Large Mechanical Structures
Authors: Harrison P. W.
Published: June 2010

This paper discusses alternative approaches to the use of the laser as a metrological tool, and considers the particular qualities required of it when the laser beam is to be used as the reference. Ways in which its usefulness can be extended by associating it with other optical equipment in order to measure parameters other than straightness are referred to. In conclusion some consideration is given to the limitations imposed by the atmosphere upon instrument performance and the ways in which, in part, they can be countered.
Paper 13: Exhaust Emissions of Vehicles Tested to the Draft European Procedure
Authors: Haynes C. D. , Southall M.
Published: June 2010

The work in this report was prompted by the probability of legislation in most European countries to limit the emission of carbon monoxide and possibly unburnt hydrocarbons from the exhausts of petrol-engined vehicles. A draft method of testing has already been agreed upon and this work was carried out in accordance with this draft procedure.

The object of the work was to establish the baseline emissions of vehicles currently in service in Great Britain and, to achieve this, approximately 100 cars, representative of the age and engine capacity distribution of the population of Great Britain, were tested.

The full test procedure consists of four cycles of a specified speed–time relationship driven from cold in which the exhaust gas is collected in bags for subsequent measurement of gas volume and carbon monoxide and hydrocarbon concentrations. For greater convenience, most tests were run from the hot condition and corrections applied to give the equivalent cold start data. These corrections, obtained by comparison of emissions from hot and cold start tests, were factors of 1·05 for mass and 0·95 for concentration.

The results of tests indicated that the average emission of carbon monoxide for cars in service in Great Britain is 172 g for the four cycles of the test procedure from a cold start, which is equivalent to a concentration of 3·4 per cent; the range of emissions is from 0·60 to 7·36 per cent. Although considered of less importance in Europe, hydrocarbons were also measured and gave an average emission of 11·0 g from a cold start.

Simple engine maintenance, such as corrections of ignition faults and carburettor maladjustments, was carried out on about half of the vehicles tested; these vehicles were representative of the sample as a whole and the maintenance resulted in a 20 per cent reduction in average carbon monoxide mass emissions and 10 per cent reduction in average hydrocarbon emissions.

Idle emission measurements were carried out with the vehicles hot. These varied from 0·2 to over 11·6 per cent carbon monoxide, with an average level of 6·1 per cent. The average hydrocarbon emission was 1550 p.p.m. Engine tuning reduced the average idle carbon monoxide and hydrocarbon emissions by 29 and 40 per cent respectively. The idle setting was found to have a marked effect on emissions over the cycle, probably because of the large percentage of time in the cycle which is at very light throttle opening or closed.

Some comparisons were also made between the results in relation to the U.S. Federal and proposed European test methods, but results were too scattered to warrant firm conclusions.
Paper 5: Some Experiments on the Mode of Action of a Diesel Smoke Suppressant Additive
Authors: Knight B. E. , Wang C. H. T.
Published: June 2010

The use of a smoke suppressant additive is very effective in reducing smoke but has only a marginal effect upon all aspects of engine performance. Photographed flame in the engine appeared to burn out earlier with the additive and at a time when gas temperatures were high. Thus, the additive was not just a catalyst for low-temperature burning of carbon. Quantitative measurements of carbon formation could not be achieved, so it is not possible to state with certainty whether the additive reduces carbon formation. The photographs do not show an observable difference of carbon formation. The most likely mechanism of action of the additive is by assisting the burning of carbon at the early stages of the engine expansion stroke.
Paper 2: Education and Training of Engineers in the U.K.A.E.A.
Authors: Hill J. F.
Published: June 2010

The U.K.A.E.A. educates and trains its staff over a very wide range of staff and subject matter. A large amount of this is done internally in a number of schools and the paper describes the arguments in favour of this and, in some detail, the way in which it is done. The different groups of the Authority vary somewhat in their methods of training, but the overall principles and objectives are similar. Particular attention is given in the paper to the education and training of already formally qualified engineers because it is in this area that there are particular differences from what is normal practice, and special attention relevant to the nature of the atomic energy industry has to be given.
Paper 4: Courses in Nuclear Science and Technology at the Royal Naval College, Greenwich
Authors: Edwards J.
Published: June 2010

The Royal Navy now has twelve submarine pressurized water reactor systems operational, or under construction, as part of its developing nuclear propulsion programme. The academic nuclear training of naval officers and civilians in support of this programme is given in the Department of Nuclear Science and Technology at the Royal Naval College, Greenwich.

Approximately 180 students per year attend the five main types of nuclear courses offered at R.N.C., which range from short introductory courses of two weeks' duration, to M.Sc. courses lasting one year. Between them, these courses provide the specialist nuclear knowledge needed by engineers and others engaged in the various supporting fields of research and development, design and construction, testing and operation, and maintenance and safety. The standards of comprehension and competence to be achieved in the longer courses are high, and the students' subsequent qualifying tests and examinations are rigorous. The academic training at R.N.C. is a complementary part of a wider training system, embracing further practical training and qualification at the Admiralty Reactor Test Establishment, Dounreay, and in the submarines, and is closely co-ordinated with the ratings' nuclear training. Feedback from the operational plants to R.N.C. is rapid, and syllabuses are continually up-dated.

The various nuclear courses at R.N.C., their aims, the topics covered, and the laboratory facilities available are described. The entry and the qualifying standards of the students are outlined.
Paper 7: Fuel Equipment for Hinkley Point ‘B’ and Hunterston ‘B’
Authors: Fortey J. , Treliving N. R. , Cooke B. F.
Published: June 2010

For economy, the same design of fuel-handling equipment is used for these two stations. On each, a single, gantry-mounted, charge machine is used for both reactors and includes, as far as possible, the features which have already been developed on earlier gas-cooled reactor stations. The charge machine, although taller, is similar to these earlier machines but considerably simpler in design, except where additional equipment has been added to suit requirements of the A.G.R. fuel assembly. These are described but are under examination to re-assess their necessity.
Paper 3: An Analysis of the Dynamics of Automobiles during Simultaneous Cornering and Ride Motions
Authors: McHenry R. R.
Published: June 2010

A mathematical model of an automobile is described, which permits the study of simultaneous cornering and ride motions on irregular terrain. A major departure from previous analytical treatments of vehicles is abandonment of the concept of a vehicle-fixed ‘hinge’ to approximate the changing virtual axis about which roll takes place.

Eleven degrees of freedom and all major non-linearities are included in the equations of motion, which are programmed for time-history solutions on a digital computer. Empirical relationships used to generate tyre forces over extreme ranges of operating conditions are presented in detail. To ease the task of interpretation of the extensive output information, a computer-graphics display technique has been developed to produce detailed perspective drawings of the vehicle and terrain at selected intervals of time during a simulated manoeuvre.

Comparisons are presented of analytically predicted vehicle responses and test results. Future applications of the described mathematical model, in research related to highway safety, are briefly discussed.
Paper 2: Driver Behaviour in Controlling a Driving Simulator with Varying Stability
Authors: Hales F. D. , Jurkat M. P.
Published: June 2010

The main content of the paper is concerned with the way people compensate their driving behaviour for degraded vehicle stability. It also outlines briefly the background of man–machine simulation and the use of driving simulators in the U.S.A. The problem was investigated by means of a fixed base driving simulator at the Davidson Laboratory as part of a larger programme concerned with driver behaviour.

The simulator has a two-degree-of-freedom analogue simulation of the vehicle dynamics. The display system is photographic using a real road film, and the vehicle is subjected to random appearing disturbances of the wind gust type. The disturbance, vehicle, and driver behaviour are recorded both as analogue and digital signals for experimental control and later data analysis.

The paper describes and gives the derived results from an experiment with nine subjects, driving two vehicles, one understeer and one oversteer, simulated to be travelling at 60 mile/h. While driving, the vehicles were subjected to a random appearing gust spectra having a maximum amplitude equivalent to 10 mile/h. Methods of assessing overall driving performance and what the drivers did in the two vehicles are developed and the results, in terms of a driving error and a control response function, are presented.

The driving error results show that, in general, drivers had significantly higher error scores with the over-steering vehicle. The driver control response function gives a measure of the reaction to the various disturbing frequencies of the disturbance. The results show that seven out of nine drivers had a control response function that was higher with the oversteering car. The remaining two subjects had the highest error scores with the understeering vehicle.

A driving effort function is derived and it is shown that, with exceptions which are discussed, the driving error may be regarded as a function of driving effort. The results substantiate the hypothesis that the driver will try to compensate for degraded vehicle stability, but show that the compensation is only partial and increased errors result.

The implications for real driving situations are that degraded vehicle stability, either of a basic vehicle or occurring during manoeuvring, will be only partially compensated for by the driver, and increased driving errors from the driver–vehicle system are likely to result.

The techniques used for the simulator experiment are suitable with only minor modifications for real driving situations.
Paper 1: Grease Lubrication of Ball Bearings in Helium
Authors: Jones J. A. , Moore H. D. , Scarlett N. A.
Published: June 2010

Ball bearings lubricated with a silica gel–mineral oil grease fail prematurely when run in helium at 200°C, failure being mainly in the form of surface damage to the bearings. Various additives have been incorporated into the grease in an attempt to overcome this difficulty, but only a combination of sodium nitrite and sodium stearate has proved completely satisfactory. The sodium nitrite, acting as an oxidizing compound, re-forms the oxide film removed by mechanical abrasion from the bearing surfaces, and the sodium stearate, acting as a boundary lubricant, minimizes this abrasion. These additives do not detract from the high-temperature and radiation-resistant properties of the grease. Depletion of the sodium nitrite, which occurs at high operating temperatures, does not limit the useful life of the grease or bearing. The grease is considered suitable for the lubrication of ball bearings in certain applications in the Dragon nuclear reactor.
Paper 3: Influence of the Atmosphere on the Endurance of Some Solid Lubricants Compared at Constant Layer Thickness
Authors: de Gee A. W. J. , Begelinger A. , Salomon G.
Published: June 2010

Friction and endurance of five powdered solid lubricants were studied on a pin and ring machine. Simple methods were developed to produce layers of constant thickness (1 μm). The ease of rubbing-in varies widely with structure and with particle size. Ease of layer formation is completely unrelated to endurance: NbSe2 is rubbed in readily, but is rubbed off directly on loading.

Layers of constant thickness from MoS2, WS2, and WSe2 powders behave roughly similarly, but MoS2 has a much longer life. The lubricant films are gradually destroyed by oxidation and therefore endurance increases in the series oxygen, air, and nitrogen (with 100 p.p.m. oxygen). The process of lubricant degradation is the same for the synthetic crystalline powders as found previously for MoS2: blistering of the run-in film surface on release of loading. Oxygen accelerates this process, leading finally to descaling and the onset of seizure. The endurance of MoSe2 goes through a pronounced maximum in oxygen–nitrogen mixtures. It is suggested that oxygen plays a dual role, first by enhancing film formation, and second by causing oxidative embrittlement of the lubricant.
Paper 3: An Externally Powered Prosthesis for the Complete Arm
Authors: Simpson D. C.
Published: June 2010

The arm which is being developed at the Princess Margaret Rose Orthopaedic Hospital, Edinburgh, has voluntary control of four degrees of freedom of the hand (three positional and one rotational), prehension, automatic control of a further degree of freedom (rotational), and can provide an indication of ‘feel’.

The control and use of a multimovement arm such as this would present an unacceptably severe task if it was attempted on a time/velocity basis. Over the last two and a half years we have been fitting a position-servo system to our present simple arm (two movements and prehension) and the children who use it have achieved a considerable degree of unconscious control and position awareness of the limb.

The results that have been achieved with position-servo control of the present arm have depended on using the proprioceptive information which has been provided by the shoulder control sites as a reflection of the positional state of the limb, and they demonstrate the quality of the match of the characteristics of the arm to those of the user.
Paper 5: Portable Power Supplies for Prostheses
Authors: Klein P. M. V. , Montgomery S. R.
Published: June 2010

Some of the problems involved in providing power storage and conversion units for complete arm prostheses are described. A comparison between existing pneumatic and electric systems shows that each has certain disadvantages. Three other power sources are considered as potential alternatives in the light of the limited available performance data and these show the need for more detailed data on the variation of power demand with time. Other factors influencing the design are discussed and suggestions are made regarding the need for further work in the field.
Paper 11: The ‘Belgrade Hand Prosthesis’
Authors: Rakić M.
Published: June 2010

The first model of a multifunctional externally powered hand prosthesis known as the ‘Belgrade Hand Prosthesis’ was developed in the Institute ‘Mihailo Pupin’ in Belgrade in 1964, and in the course of 1966–67 an improved model was developed. The further programme of work envisages a two-year engineering and functional evaluation of the prosthesis on the patients.

A detailed description of the improved mechanical solution of the ‘Belgrade Hand Prosthesis’ is given in this paper, and two variants of control logic are described.
Paper 15: Efferent and Afferent Control of an Electromyographic, Proportional-Rate, Force Sensing Artificial Elbow with Cutaneous Display of Joint Angle
Authors: Mann R. W.
Published: June 2010

The ideal replacement for an amputated human limb would achieve a symbiosis with the intact human system. It should not only appear anthropomorphic; it should perform as if it were a natural extension of the human central nervous system. A prosthetic elbow for above-elbow amputees has aimed at this objective and has undergone considerable engineering refinement in parallel with simulation and evaluation studies with amputees. Efferent control is achieved by surface detection of electrical potentials generated by neuromuscular activity in the otherwise non-functional muscles in the amputees stump. Electrical intensity, related to conscious effort on the part of the amputee, controls in a proportional fashion the battery power delivered to the electric motor–gear–chain–ballscrew–linkage which rotates the elbow. Afferent reflexive feedback to the human nervous system of force-sensing information is achieved by means of a strain gauge element whose electrical output opposes the EMG signal in the limb control system. Thus a sudden increase of terminal load must be compensated for by an increase in human-generated EMG or the elbow joint will relax. Volitionally, the support or movement of greater terminal loads requires greater conscious effort. Afferent nervous system information on elbow angle will be provided by a novel vibratory display on the skin of the amputee's stump to supplement the usual visual cues. Research on this cutaneous presentation of kinaestheses indicates information transmission approaching that provided by the normal intact physiological system.
Paper 16: A Preliminary Investigation into the Effects of Applying a Locking Device to a Position-Controlled Externally Powered Prosthesis
Authors: Pottinger J. M. , Ring N. D.
Published: June 2010

The application of position control to externally powered prosthetic arms leads to increased function and versatility when compared to a prosthetic system with open-loop control. However, various compromises are necessary owing to the limited number of available control sites. An investigation is being conducted into the possibility of combining the advantages of position control during the dynamic phase of movement with the locking facility of velocity–time control during the static phase, which leads to a larger number of available control sites and thus a greater number of degrees of freedom.
Paper 19: Emgor: An Implantable Sensor for Myoelectric Signals
Authors: Reilly R. E.
Published: June 2010

Shortage of independent control signals limits the ‘cleverness’ of externally powered limbs. Surface methods of sensing muscle activity give very crude reproduction. Implanted sensors ought to extract some of the untapped skill of muscles, and help establish how it may be applied.

The Emgor is a sensor for myoelectric signals which is intended to be permanently implantable, with this aim in view. The paper describes the sensor and its associated electronics, and gives details of its performance.