bluuebunny/crossref_metadata_2025 huggingface dataset:
Torque Transfer in Automotive Brakes
Authors: Sinclair David
Published: June 2010

Recorded brake evaluation tests in automobiles and in a dual-brake inertia dynamometer show continual transfer of torque among the several brakes. The individual brakes seldom exert the designed relative braking torque, because the coefficient of friction is seldom the same in each. Experimental results are given to show torque transfer caused by fade following high temperatures and by recovery following lowered temperatures and wear. Differential equations are derived expressing the decrease in coefficient of friction (fade) as a function of time and the temperature rise induced by frictional work. The solutions show torque transfer similar to that observed.
Supercharging the 1 1/2-Litre V.16 BRM Racing Engine
Authors: Wilde G. L. , Allen F. J.
Published: June 2010

The BRM racing car project was initiated in 1945 by Messrs Automobile Developments Limited and supported by the British motor industry. The engine was a 1 1/2 litre V.16 cylinder supercharged unit required to give 400 b.h.p. This paper gives an account of the work carried out by Rolls-Royce Limited in the design, building and development of the supercharger, and also deals with the problems of estimating the power output of the engine based on a method for calculating the charge consumption. The problems encountered in the development of the power unit are discussed, and the experience gained may be of some interest to others who may be considering a supercharged engine for the new racing Formula in 1966.
Tyre and Vehicle Vibration
Authors: Barson C. W. , Gough V. E. , Hutchinson J. C. , James D. H.
Published: June 2010

An installation specifically designed for the measurement and analysis of vibrations generated at the tyre to road contact, of vibration through tyre, vehicle suspension and body structure is described. Results of tests on rolling drums, including tests on drums with special test surfaces and tests on hydraulic and electromagnetic vibrators designed to feed vibrations into the tyre at ground contact are given. As the hydraulic vibrator is capable of vibrations in the three directions, vertical, longitudinal and lateral, examples of the attenuation during transmission through tyre and suspension are given. Road test recording equipment is available and it uses the analysis equipment installed for the laboratory installation of vibrators and drums: elimination of

long delays in analysis is given attention.
First Paper: Tyre to Wet Road Friction at High Speeds
Authors: Allbert B. J. , Walker J. C.
Published: June 2010

The general problem of loss of tyre grip on wet road surfaces is discussed. The initial section of the paper covers a description of the testing techniques employed for the investigations reported. These include both road and indoor rig techniques developed to study limiting tyre braking and cornering properties under a wide range of operating conditions.

The level of friction between a tyre and a wet road is primarily related to the ability to remove a water film from the ground contact area. The contact area is considered to be separated into three effective zones. Initially the ‘bulk’ of the film is displaced leaving a thin residual film to be penetrated at, or absorbed from, the interface before substantially dry contact can be established. The size of this dry area, at the rear of the contact zone, has an overriding control on the level of available friction and is dependent upon the time occupied in displacing the water film in the frontal zones.

An increase in the peripheral speed of the tyre reduces the time available for water displacement and effectively shortens the area of actual ground contact. In the limiting condition the vertical load on the tyre becomes entirely supported on the water film and the condition of aquaplaning exists. The requirements for this condition to occur are briefly discussed.

Tread pattern and road surface design are shown to exert a considerable influence upon the rate of water displacement from the contact area and hence upon the relative sizes of the water-supported zones.

The forces developed in the dry zone at the rear of the ground contact are dependent upon the frictional characteristics of the tread material.

A section of the paper considers the wide scale effects of tread pattern, tread material and road surface characteristics and discusses the nature of the interactions between these three variables.

Some results of recent studies related to different types of tread pattern, specific pattern design features and the effect of tyre casing construction are included.

Future potential development of the tyre contribution is reviewed.
An Abrasion Test for Use in Agricultural Engineering
Authors: Davies G. R.
Published: June 2010

An abrasion test has been developed and used to compare the resistance to abrasion of a range of plastics and metals. The test is primarily intended for use in agricultural engineering and has been designed to cover a wide range of conditions such as occur in this industry. One of the main features of the test where it differs from most others is that it uses loose, and not bonded, abrasives. The results obtained so far, on about fifty plastics and metals, emphasize the importance of the resilience of the material in reducing abrasive wear. They also show that the resilience, or, more specifically, the vibration characteristics, of the support for the specimen, can. affect the rate of abrasion.

Plastics test specimens appear to wear into two distinct final shapes and this shape seems to depend on both the material and the test conditions; it could possibly result from the two forms of abrasive wear already described in the literature. The possibilities of further work are discussed.
Characteristics of New Ignition Systems to Improve Engine Performance
Authors: Teasel By R. C. , Miller R. D.
Published: June 2010

The increasing use of spark ignition engines throughout the world has confronted the engine designer with new problems such as air pollution, world-wide temperature extremes, as well as legislative, economic, and human considerations. To meet these situations and improve the competitive position of the spark ignition engine requires considerable research and development effort.

This paper reports on work conducted by Champion Spark Plug Company in attempting to evaluate the potential contribution that ignition system and spark plug designs can make towards improving spark ignition engine operation.

Almost all the work reported here covers investigations in current large displacement United States passenger car engines.

The three main characteristics of the overall ignition systems that are investigated are (1) the available output voltage characteristics of the ignition systems; (2) the effect of the ignition system spark discharge characteristics on engine performance; and (3) the effect of several spark plug design features on engine performance.

This investigation shows that the inter-relationship of the ignition system spark discharge characteristics and the spark plug design requires that the overall evaluation must consider the dependence of both items. It also suggests that significant improvements can result in other United States and European engines, through the careful evaluation of ignition system and spark plug designs.

The results of this work indicate that a fast rise time, short arc duration system results in reduced spark plug gap growth and better resistance to spark plug fouling. However, the arc duration must not be shorter than a minimum value, or a loss in engine performance may result. High output systems are desirable as they provide a higher voltage reserve to provide longer spark plug life, but the higher voltages that occur with the larger spark plug gaps can stress other ignition system components.

The spark plug designs which incorporate a projection of the spark plug gap result in better performance in the engines tested, and possibly even reduce exhaust emissions.

Certainly other features which engine manufacturers must consider, which are not discussed in detail here, are costs, durability, and maintenance of the new systems. At least one other important related problem is that of interference.
First Paper: Some Considerations on Detecting and Preventing Spark Knock in the Car Engine
Authors: Addicott J. L.
Published: June 2010

Spark knock is defined. Reasons are advanced for the continuing need to prevent knock but the claim that loss of power and engine damage will necessarily occur when operating at low engine speeds under knocking conditions is challenged.

An outline is given of the types of gasolines that are available on the market for the car engine. The necessity to have available in engine development work reference fuels which broadly represent the possible alternatives that will be met in the market is shown. Suggestions are advanced for suitable reference fuels.

Test bed, road and vehicle dynamometer work for engine development related to gasoline knock is discussed. The effects of engine component temperatures, of carbon deposits and distributor drive lash is given. The use of octane requirement survey data to the designer is shown.

The importance of the minimum advance for best torque curve, the choice of an ignition advance curve and recommended ignition settings related to knock-free performance are discussed.

The place for aural methods and instruments for the detection of knock is given.
Third Paper: The Influence of Engine Design on Spark Knock at High Speeds
Authors: Perrett J. B.
Published: June 2010

Modern motor roads permit cars to be driven at high speeds for many miles. In these circumstances it is possible for engines to be operating in a condition of spark knock for a considerable time. Such knock might not be detected by the driver, but could initiate a chain of events leading to damage to the engine.

A realistic procedure has been devised for carrying out tests for spark knock at high speeds, employing cars mounted on vehicle dynamometers. Tests on 30 European car models, all having manual transmissions, led to the critical knock speed concept for making comparisons between the high speed knock susceptibilities of various designs of engine. These comparisons have shown that, in service, over-advanced spark timing is frequently the prime reason for the occurrence of high speed knock.

With spark timing set at the minimum advance required for the engine to develop its best torque, octane requirement is influenced by compression ratio, brake horsepower per litre, cylinder swept volume and disposition of the exhaust valves. Also to a small extent, by combustion chamber design and the amount of induction heating employed. Given attention to the above factors, it is felt that the high speed anti-knock requirements of the present generation of engines can be met by currently marketed gasolines of 98/99 Research octane number (ON).
The Relationship between Gasoline Composition and Spark Knock at High Engine Speeds
Authors: Grevett By S. P. , Tharby R. D.
Published: June 2010

Since spark knock at high engine speeds is becoming an increasing problem with modern Western European cars, the relationship between this phenomenon and gasoline composition has been investigated.

The engines prone to high speed knock are generally those of relatively high specific output (high bhp/litre) compared to the general car population. In such engines, spark knock at high speeds was found to be more closely related to Research ON and olefin content than to either Research ON and sensitivity or Motor ON alone.
Second Paper: The Design of Ambulances
Authors: London P. S.
Published: June 2010

Although only about 5 per cent of the work of ambulance services concerns emergency cases, it is the seriously ill or injured patients that pose the most difficult problems in design. Much of this difficulty springs from the fact that only a few hundred ambulances are required each year, which means that vehicles produced as a result of special research and design would be very expensive.

The following objectives should be accepted.

(1) To eliminate jolts without causing nauseating swaying. (2) To provide a vehicle in which a stretcher trolley can be firmly fixed either in the centre of the vehicle or along each side, where trolleys could, if necessary, be used as seats. (3) To provide the stowage space for necessary medical and some light rescue equipment. (4) Easy entry for stretcher trolleys at the rear and easy passage between the crew and patient compartments. (5) Ideally, the suspension should be appropriate for a load of two crew, two stretcher patients and necessary equipment but in many cases economic considerations make it desirable to design ambulances that can carry up to ten seated persons.

The only justification that a surgeon with very little mechanical knowledge can have for addressing this Institution on the subject of the design of ambulances is an interest in the subject born of the awareness of its importance, combined with detailed knowledge of what facilities seriously ill or seriously injured persons need while being taken to hospital.
Optimum Damping in a Randomly Excited Non-Linear Suspension
Authors: Thompson A. G.
Published: June 2010

Analogue computer studies of an automobile suspension on a simulated random road show that optimum ride and road holding can be achieved with linear damping for all magnitudes of road roughness. Unsymmetrical damping, however, provides better isolation from large bumps and obstacles at the expense of only very moderate increases in the mean-squared values for random inputs. Optimum values for the ratio of bump to rebound damping rates are obtained by use of an integral-square criterion. For a linear system the effects of the seat dynamics and road power spectrum characteristics are illustrated using the results of a digital computer program. The influence of the non-linearities on mean-square values is analysed theoretically and the statistical describing function method applied.
First Paper: Emission Control by Exhaust Manifold Reactor—An Initial Study for Small Engines
Authors: Lawrence G.
Published: June 2010

This paper describes the experience gained in a first exercise to investigate the potential ability of exhaust thermal reactors to reduce specific exhaust pollutants from European sized engines below the control levels likely to be legislated in the longer term.

It concludes that such systems are both efficient and viable, subject to adequate development, and may become essential if the political trends towards increasingly stringent depollution standards continue.
Second Paper: Recent Developments in Exhaust Manifold Reactor Systems
Authors: Cantwell E. N. , Rosenlund I. T. , Barth W. J. , Ross S. W.
Published: June 2010

Exhaust emission control systems employing air injection and exhaust manifold reactors in place of conventional exhaust manifolds have been developed to control vehicle emissions to 0·25 gram (20 p.p.m.) of hydrocarbons and 5·0 grams (0·22 per cent) of carbon monoxide per mile. These low emission levels have been achieved with good driveability, good vehicle performance and very little loss in fuel economy. Durability tests of a number of exhaust manifold reactor systems indicate that acceptable life in consumer service can be attained. Non-nickel alloy steels developed by specialty steel manufacturers, and based on the iron-chromium- aluminium system, appear to be useful materials of construction for reactors. These alloys coupled with the now demonstrated simplifications in reactor design offer one route to lower ultimate costs of these units. The commercial development and application of exhaust manifold reactor systems seems entirely feasible.
Paper 1: The B.M.C. ‘A’ Series Engine
Authors: Appleby W. V.
Published: June 2010

This engine was first introduced in 800 cm3 form in 1952, and the paper traces its subsequent design history, culminating in the 1098 cm3 version for transverse installation.

Originally designed for the post-war Austin 7 saloon, this engine was reclassified as the ‘A’ series unit at the time of the formation of the British Motor Corporation. It was then decided that this unit and its derivatives would power all the smaller range of B.M.C. cars.

After a logical development to 950 cm3 a new design situation was created by the concept of the ADO.15 which subsequently evolved into the Mini 7 and Mini Minor. During this period both two-stroke engines and a two-cylinder version of the ‘A’ series were developed, but were discarded in favour of the 850 cm3 four-cylinder unit.

The reasons for this decision, which include both economic and technical considerations, are discussed in detail. The modifications required to suit the transverse installations are also considered.

A further design challenge was presented by the power requirement for the ADO.16, especially as the relatively high power/weight ratio of the Minis had set a high standard in this respect. The decision was complicated by the existence of an alternative engine in the design stage, and the rigid limitations imposed by existing production plant on the basic dimensions of the ‘A’ series.

Previous design criteria had to be discarded in order to make the 1098 cm3 possible, and to establish it as a reliable high-performance unit. The situation was complicated by the need for still greater performance in sports car installations.

Apart from specific details of changes in component design which included the adoption of new materials when required, the paper emphasizes the importance of close liaison between design and development.
Paper 10: Stresses in the Contact Zone
Authors: Ollerton E.
Published: June 2010

The paper deals with the contact-stress problem with particular reference to adhesion in the rail-wheel contact situation.

The methods of calculation of the size, shape and orientation of the contact area are described, and confirmed by the results of frozen-stress photoelastic tests. The test results are confined to the contact surface, since sub-surface stresses are not directly relevant in the adhesion problem.

The distributions of surface shear stress resulting from the application of tangential forces to different shapes of contact area are described for static and rolling conditions. Methods of calculating the creep of rolling bodies are also considered.

The problem of bodies rolling and spinning about an axis normal to the contact area is not so well understood, but a brief description is given. The effects of bending stresses in rails and of the size of the contact area in relation to the railhead are discussed briefly.
Paper 6: Complete Characteristics for a Single-Stage Axial-Flow Fan
Authors: Turner R. C. , Sparkes D. W.
Published: June 2010

The characteristics of an axial-flow fan, pump or compressor stage are usually established by prediction or test for the normal directions of rotation and flow only, the flow range being restricted to fairly narrow limits.

There are occasions, however, when it is desirable to know the performance over a wider range of conditions. Fans in certain types of aircraft jet engines may have to work in reverse through flow or may be required to windmill freely. Fans in high-pressure closed-circuits, or in parallel with other fans, may also have unusual conditions imposed on them if some part of the system fails.

This paper presents the characteristics of a single-stage axial-flow fan for normal and reverse rotation and for a wide range of normal and reverse through flow. Several methods of presentation are employed. Published data on the subject is scarce, and it is thought that these characteristics will give a general picture of the trends to be expected with other designs of fan operating under comparable conditions.
Paper 10: Unsteady Flow in Simple Branch Systems
Authors: Benson R. S. , Woollatt D. , Woods W. A.
Published: June 2010

The paper describes a theoretical and experimental investigation into unsteady flows in simple branch systems. In order to simplify the analysis one-dimensional unsteady flow theory is used to analyse the wave action in the pipes. The method of characteristics is used for this purpose, and both homentropic and non-homentropic flows are investigated.

The boundary conditions at the branch are represented by quasi-steady flow theories. Two such theories are examined, the first called the constant pressure theory assumed no pressure change across the branch at the junction. A full graphical treatment is given elsewhere (4). In the paper the assumptions and the formulation of the equations for an electronic computer are briefly discussed. The second method assumes a pressure drop across the branch at the junction. An approximate theoretical method of estimating the pressure drop with certain types of flow is given. Using experimentally determined steady flow loss coefficients at the junction the expressions used in the second method are formulated for direct computation using a digital computer.

The results are given of an extensive experimental investigation to test the validity and limits of the theories described above. Steady flow experiments to evaluate the loss coefficients at the junction over the range of pressure and flow directions covered by the unsteady tests are described. The unsteady flow tests on a special multi-cylinder pulse generator are discussed in detail. The results show that under certain conditions the calculated pressure diagrams using constant pressure theory do not agree with the experimental diagrams, both the pulse shape and amplitude being incorrect. Using the pressure drop theory together with experimentally determined steady flow loss coefficients there is considerable improvement in the theoretical diagrams. Agreement is obtained over a wide range of flows.
Paper 12: Turbulent Flow and Heat Transfer in Concentric and Eccentric Annuli
Authors: Lee Yung , Barrow H.
Published: June 2010

Fluid flow and heat transfer in non-circular passages, with peripheral variation of heat flux around their boundaries, is of particular interest in the nuclear engineering field. This paper deals with heat transfer to air (Prandtl number ⋍ 0.7) in fully-developed turbulent flow in an annular passage, the outer boundary of which is insulated.

Experiments have been conducted on annuii whose radius ratios are 1.632, 2.583, and 3.875 over a Reynolds number range 10 000–50 000. Pressure drop, velocity and temperature distributions in the cross-section have been measured over the whole range of eccentricity of the annulus geometry. The effect of eccentricity on average friction, average heat-transfer coefficient, and wall temperature distribution for uniform heat generation within the heated boundary has been studied. The results of the experimental programme are compared with the semi-theoretical predictions and experimental data of other workers in this field.

For completeness, a theoretical equation for the heat-transfer coefficient in an internally heated concentric annulus has been derived.
Paper 15: Performance of Extended-Surface Tube Matrices for Gas-Liquid Heat Exchangers
Authors: Rounthwaite C. , Nicholson V.
Published: June 2010

Heat-transfer experiments have been undertaken, using two different test facilities, on a wide variety of tube bundles arranged with warm gas flowing either across, or parallel to, the outside of the tubes and with cool water flowing inside them. The cross-flow tube bundles include radial-finned tubing in various ‘in-line’ formations, as well as a staggered arrangement of elliptical-section finned tubing. Of the two axial-flow tube bundles considered one is of radial-finned tubes and the other of longitudinal-finned tubes.

The gas-side heat-transfer and pressure-drop performance of all these tube arrangements are presented firstly in the form of the customary non-dimensional relations. The performances of the tube matrices are then compared using a number of utilization parameters, based on theoretical expressions of Colburn, covering not only the main factors involved in the cost of heat exchangers, but also the return of heat transfer for the gas-side pressure drop expended. By plotting graphs connecting these parameters, the relative merits of the various tube configurations in actual heat-exchanger applications can be assessed, and conclusions drawn as to the most suitable one to adopt for a particular purpose. A most useful graph is one connecting the parameters expressing the compactness of the tube matrix and the gas-side fluid resistance (see Fig. 15.8). Such a relation shows that the staggered cross-flow arrangement of elliptical tubes gives rise to reasonably compact matrices with only a moderate gas-side pressure drop. The cross-flow bundles of circular-section tubing, however, can result in extremely compact matrices having a high pressure loss, whilst the axial-flow configurations have exactly the opposite characteristics.
Paper 5: Actuator Disc Theory of the Compressible Flow in Free-Vortex Turbo-Machinery
Authors: Hawthorne W. R. , Ringrose J.
Published: June 2010

The actuator disc method, in which each blade row of a turbo-machine is represented by a plane, axisymmetric discontinuity in the flow field, is used to produce an approximate solution of the problem of compressible, irrotational flow through an axial compressor or turbine.

The flow equations are linearized and a solution for a single, isolated disc is found. The effects of mutual interference between neighbouring discs are studied for two adjacent discs. A method for extending the solution to any number of discs is outlined. Examples showing applications of the method are given and experimental measurements made near the inlet guide vanes of an axial compressor agree well with the theoretical predictions. A new exact solution for two adjacent actuator discs is also given.
Paper 3: Use of Higher Stresses in the Design of Pressure Vessels
Authors: Raymond M. J. M. , Osbeldiston K.
Published: June 2010

This paper summarizes very briefly the history of the use in Germany and elsewhere of design stresses for vessels which are higher by up to 50 per cent than those allowed by British Standard 1500 and the American Society of Mechanical Engineers' Code, and of the approach of Imperial Chemical Industries to this problem.

On the technical side the criteria which should govern local stresses in pressure vessels and their permissible values were then considered, an aspect of design which has received less public discussion than the estimation of stresses due to local loads. The conclusions reached have formed the basis of recommendations submitted in collaboration with other interested organizations to the British Standards Institution.

The use of higher design stresses implies that there is a smaller margin for errors in design or shortcomings in quality of materials or manufacture. The administration of the pressure vessel code in Germany is reviewed and comparisons are drawn with the bodies available for similar purposes in Britain.
Paper 7: Torsional Oscillation of Systems Which Embody Couplings Haying Periodically Varying Velocity Ratios
Authors: Porter B.
Published: June 2010

The results presented in this paper indicate the conditions under which oscillations of large amplitude occur in systems which embody couplings having periodically varying velocity ratios. Experimental results relating to one- and two-degree-of-freedom Hooke's joint systems are given and are compared with theoretical predictions.
Paper 1: A Survey of Marine Diesel Propulsion Machinery
Authors: Cook R.
Published: June 2010

The present supremacy of the direct-drive diesel engine for ship propulsion is illustrated statistically and this is followed by a consideration of factors peculiar to marine propulsion machinery. The principal technical factors of modern diesel propulsion machinery are then described and the lines along which development is likely to take place are discussed. Consideration is also given to the alternative forms of propulsion system which have been advocated in recent years and some conclusions are hazarded regarding future prospects.
Paper 7: A Comparative Examination of Some Potential Inorganic Lubricants on the Shell Four-Ball Tester and on a Crossed-Cylinder Wear Machine
Authors: Middleton K.
Published: June 2010

Several workers have reported the use of mixtures of solid lubricants in dry film systems and, in particular, combinations of various metallic sulphides with molybdenum disulphide (MoS2) in the dry state have been shown to be successful. Here, data obtained using a Shell four-ball tester is presented in which selected inorganic sulphides and oxides dispersed in oil have been examined; the variation in the size of wear scars with load in the range 20 to 800 kg is shown. Examples are also given of the variation in the wear-load curve with concentration of dispersed solid, where it is shown that the amount of wear decreases with increasing concentration of solid up to an optimum concentration of approximately 0·7 per cent by volume, with the exception of sulphur, which performs equally well at all concentrations between 0·2 and 20 per cent by volume.

The same solids have also been examined in the form of dry rubbed films in three atmospheres on a crossed-cylinder wear machine, and only MoS2 has been found to provide effective lubrication as a dry unbonded film.
Paper 9: Friction between Unlubricated Steel Surfaces at Sliding Speeds up to 750 Feet per Second
Authors: Williams K. , Giffen E.
Published: June 2010

A brief description of the apparatus used for making the measurements discussed in this paper is followed by a record of the intended scope of the investigation.

The experimental programme conducted is outlined, the results discussed and presented in graphical form. The experimental results are supplemented with photographs of the contact surface of the specimens when examined under the microscope.

The experimental results are analysed in terms of the effects of the variables in the investigation upon the coefficient of friction; the most important variables were sliding speed and normal load. The effects are also examined by reference to the photographs of the surfaces. The photographic evidence leads also to conclusions regarding the relation between the state of the oxide layer, the mechanism of the frictional process, and the resultant value of the coefficient of friction.
Paper 11: The Use of a Motored Engine to Study Piston-Ring Wear and Engine Friction
Authors: Pike W. C. , Spillman D. T.
Published: June 2010

The paper describes a study of the conditions which lead to mechanical, or attritive, wear of a top piston- ring. A motored single-cylinder engine was used, and piston-ring wear measurements were made using a radioactive tracer technique. By connecting the inlet and exhaust ports together and pressurizing the system with nitrogen, peak cylinder pressures could be matched to those in a firing engine and corrosive wear minimized. Ring belt oil viscosities were matched to those in service either by using low-viscosity oils or by restricting the cooling.

Wear was caused, under steady-speed conditions, by increasing the peak pressure or the cylinder-liner temperature. However, even under the most severe conditions, the wear rate eventually became negligible with the liner surface becoming highly polished. Under comparable conditions in a fired engine a steady rate of wear was observed.

It was found that large variations in piston-ring wear could occur without any detectable change in the motoring torque. Torque was linearly related to the peak cylinder pressure. The component of the motoring torque attributable to the piston assembly friction varied as the square root of the ring belt oil viscosity.

The results suggest that, in a fired engine, hydrodynamic lubrication should be attainable throughout the stroke if roughening of the surfaces by the effects of combustion products could be prevented.
Paper 21: Stability of a Balanced Shaft Running in Cylindrical Journal Bearings
Authors: Someya Tsuneo
Published: June 2010

The stability of a shaft, free of unbalance, running in cylindrical journal bearings, was studied mathematically. Stability charts, calculated through linear theory, show especially the influence of changing the width ratio B/D on stability. Calculation of non-linear vibration yielded good agreement with previous experimental results, both for the ‘half-frequency whip’ and the ‘natural frequency whip’. ‘External’ damping force proved to be necessary for the finite rotor amplitude. With a simple damping formula stationary whip was then calculated. This result also seems to be proved by the experimental results.
Paper 9: Ceramic-Metal Composites: Nucerite
Authors: Wood W.
Published: June 2010

This paper describes ‘Nucerite’, a new material of construction consisting of a ceramic-metal composite which has improved mechanical strength and abrasion resistance over glassed steel. A wide range of ceramics is available and these can be bonded to a range of base metals, thus giving a very wide choice of properties.

An outline of the induced crystalline structure in the ceramic shows how Nucerite is suitable for high temperature use together with good corrosion resistance. The application of Nucerite in the chemical and related industries shows how its versatility can be used to solve high temperature, corrosion, and abrasion problems.

Examples of items of equipment, together with the conditions under which they are being used, confirms that there is a big future for Nucerite as it is developed and its properties are improved even further.
Paper 3: The Influence of Track Twist on Vehicle Design
Authors: Batchelor G. H.
Published: June 2010

The paper draws attention to the importance of the torsional stiffness of vehicle bodies as well as the adequacy of suspensions in limiting pseudo-static wheel load variations caused by uneven track.

The magnitude and incidence of effective twist gradients in track are considered, together with suitable criteria for vehicle design. Expressions are quoted for the evaluation of wheel load change for bogie and four-wheeled vehicles on track with continuous twist and also effective twist due to local low points. Torsional stiffness data for a range of representative vehicle bodies are given together with several numerical examples which serve to illustrate the effect of the parameters involved.
Paper 4: Instruments Used in the Development of Diesel Engines
Authors: Daft C. H. J.
Published: June 2010

An account is presented of some experiences of the various techniques and instruments used in the development of diesel engines. The measurement of mass fuel consumption by electronic methods to reduce testing time is detailed, together with a discussion on the elimination of the consequent inaccuracy. The accuracy of single-cycle techniques and the point-by-point method for dynamic pressure measurements are considered together with frequency-modulated techniques, direct current techniques, oscilloscopes, and galvanometer recorders.

Details of the response time and repeatability of fast-response thermocouples for gas temperature measurements are discussed. The use of digital equipment such as voltmeters for strain and counters for speed and flow measurement is also described.
The Engineer's Viewpoint
Authors: Saunders Owen
Published: June 2010

This paper discusses the academic policy of a mechanical engineering department in a university and a college of technology and considers its relation to the policy of other departments with regard to the scope and range of undergraduate and postgraduate studies. The special circumstances of academic staff and the need to minimize the burden of administration is emphasized.

The considerations affecting the arrangement of facilities including lecture rooms, drawing offices, laboratories and workshops and the special problems occurring in the provision of services, suppression of vibrations and the disposal of exhaust fumes from engines are discussed and the need for providing student and staff amenities is made plain.

The appendices include details of the Mechanical Engineering Department at Imperial College.
Paper 1: The Architect's Approach to the Design of Mechanical Engineering Departments
Authors: Stillman John
Published: June 2010

This paper discusses decisions to be taken at three stages in the design of new mechanical engineering departments for universities and colleges of advanced technology. These decisions, which are to be taken within a framework of educational and financial policies, are concerned with the brief, the planning and the structure.

Planning and structure include all the three-dimensional aspects of design. Decisions are centred on the problem of flexibility and how this relates to a number of factors including costs, service provisions, and the architectural expression. Implications of the design decisions are illustrated by reference to the evolution of the plans for the engineering complex at Brunei College, now under construction, and by other British and continental examples.

In dealing with the construction of heavy laboratories notes are included on lighting, sound insulation and vibration, mechanical handling and methods of integrating services.

Throughout, emphasis is placed on co-operative working between the client and the professional team, which although it is led by the architect, must include the consulting mechanical, electrical and structural engineers and the quantity surveyors.
Paper 3: The Enlarging of an Engineering Faculty on an Existing Site
Authors: Webb C. R.
Published: June 2010

The paper deals with the execution of a post-war plan to create new buildings for the Faculty of Engineering at Queen Mary College, one of the four Engineering Schools of London University.

The buildings were to provide for an annual undergraduate intake of 150 together with sixty postgraduate students engaged in research.

The site of the new buildings was adjacent to that of the existing College; however, it faced a main traffic route unlike the secluded existing site, so that special problems arose. Current building regulations affected the design and planning of the facilities and, in general, added to the cost. Noise and vibration arising internally had to be carefully considered. With the need to site some heavy laboratories on upper floors, special measures were needed to deal with the handling of equipment.

To deal with unpredictable changes in the curricula, the maximum flexibility in the use of rooms was desirable and means for the easy installation of additional services at any time was built in.
Paper 4: The Adaptation of an Existing Industrial Building as Temporary Accommodation for a Department of Mechanical Engineering at a College of Advanced Technology
Authors: Chisholm A. W. J. , Taylor F.
Published: June 2010

A brief account is given of the reasons for deciding that a complete department should be moved to temporary premises rather than to use these premises to provide additional space for a number of departments.

Consideration of the requirements of each section of the department, such as headroom, materials handling problems, machine foundations and the like are considered.

A brief description of the building giving the main features of construction and an assessment of the accommodation it offered is given, together with details of how the accommodation was to be utilized by the various sections of the department. An account of the work to be done and the assistance obtained from consultant architects and from college staff is then provided.

The actual transfer of the equipment to the temporary premises and the problems encountered are considered, together with the phasing of the work. The final layout of the laboratories and the problems encountered since moving in are examined.

The paper concludes with a general examination of the value of the move in relation to the provision of permanent accommodation for the department concerned to be provided in the college building programme.
Paper 33: Heat Transfer Effects Arising from arc Rotation in Plasma Arc Heaters of the Self-Induced Magnetic Field Type
Authors: Bunt E. A. , Olsen H. L.
Published: June 2010

This paper is concerned with an analysis of the thermal behaviour of high input power (∼ 15 megawatt) arc heaters operating at values of total (bulk) enthalpy up to 2500 Btu/lb. Such heaters are currently in use to supply air for aerodynamic testing purposes, including subsonic turbulent pipe flow, the operation of propulsion tunnels with ‘full’ temperature simulation, and supersonic combustion ducts. The electrode system is essentially a ‘rail accelerator’ adapted for continuous operation by making it re-entrant, the self-induced magnetic field bringing about rapid movement of the arc roots to prevent destruction of the electrodes. The rate of rotation of the arc column (which is subject to aerodynamic drag) is shown to be a function of apparent electrode gap, current, and the stagnation temperature and pressure in the arc chamber. A distinction can also be drawn between ‘long’ and ‘short’ arcs, depending on whether the inter-electrode gap is large or small. The value of the arc rotation rate ω (which ranges between approximately 50 and 1000 per sec) has a considerable bearing on the thermal efficiency of short-gap arcs, on account of the dependence on it of the convective losses. Since the chamber gases radiate much more strongly than air uncontaminated by electrode material, convective and radiative losses are distinguished by solving for first-power and fourth-power dependence on temperature difference with the walls; the convective losses are examined in conjunction with a vortex model of the gas behaviour.
Paper 29: The Mechanism of Relative Eddy Flows in Mixed-Flow Turbo-Machines
Authors: Lewis R. I.
Published: June 2010

In mixed-flow turbo-machines the energy transfer results partly from fluid deflection and partly from Coriolis forces due to the radial motion. The relative motion produces another effect not occurring in axial machines, namely that of slip or relative eddy. In this paper a conformai transformation theory is developed for radial bladed conical flow machines along similar lines to that of Busemann.

The flow is regarded as the superposition of source/vortex prewhirl flow and a blade lifting vortex. The lift components due to Coriolis forces and deflection are thus separable. The theory also permits the calculation of surface velocities and streamlines. The main intention is to provide an exact theory for comparison with the extended Schlichting analysis of Pollard.
Paper 23: An Experimental Investigation of Non-Steady Flow in a Radial Gas Turbine
Authors: Benson R. S. , Scrimshaw K. H.
Published: June 2010

Comprehensive steady and non-steady flow tests on a small radial turbine turbo-charger are given. Steady flow tests included both full admission and partial admission over the whole speed and pressure range from zero flow to maximum flow.

Non-steady flow tests were carried out over a pulse frequency range from 30 to 70 pulses/s and turbine speeds from 30 000 to 60 000 rev/min with the turbine coupled to the exhaust system of a six-cylinder pulse generator under partial admission conditions. Extensive transient pressure and temperature measurements were taken upstream and downstream (pressure only) of the turbine. The total mass flow and power were also measured. A quasi-steady flow analysis was carried out using the steady flow test data.

The tests results showed that for a six-cylinder exhaust pipe configuration, with two exhaust pipes entering separate nozzle segments in the radial turbine, the quasi-steady flow analysis using partial admission data grossly underestimated the mass flow and power output of the turbine. Using full admission data the ratio of measurement mass flow and horsepower to the calculated mass flow and horsepower was nearly always greater than unity. Furthermore, the average turbine efficiency was greater under non-steady flow than under steady flow. The magnitude of the recorded effects was dependent on the pulse frequency and turbine speed.
Paper 22: The Extension of Schlichting'S Analysis to Mixed Flow Cascades
Authors: Pollard D.
Published: June 2010

An analysis is given which enables the performance of a rotating cascade in a mixed flow machine to be calculated. A method of singularities previously used for obtaining the flow through a cascade of blades in two dimensions has been modified to take into account the effects of the relative motion between the fluid and the machine, which includes vorticity.

The flow through the mixed-flow cascade is specified by a meridional stream surface which is mapped on to a two-dimensional plane by means of a conformai transformation. Distributed vorticity in the two-dimensional plane is related to the relative vorticity in the meridional plane through the transformation, and a solution of the flow through the cascade in the two-dimensional plane with the distributed vorticity gives a result which includes the ‘slip’ effect, as well as the usual cascade deviation.

Examples of the calculation of slip factors for radial flow machines are given and show excellent agreement with exact theories. The method can be used also for mixed flow machines, and flow angles and pressure distributions may be calculated.
Paper 12: Derivation of Furnace Heat Transfer from Fluid Dynamic Behaviour
Authors: Anson D.
Published: June 2010

The principles underlying radiant heat transfer in boiler furnaces are fundamentally simple, but their application requires a knowledge of empirical quantities describing the emissivity of the flame and the boiler surfaces and the relationship between their geometries.

This paper draws attention to the dependence of local heat release rates on fuel/air mixing. In the case of a downshot coal-fired furnace, the performance of which was investigated in detail, the size and position of the effective flame envelope could be derived from a knowledge of the flow and mixing rates. These in turn should be capable of being measured on isothermal models, and research should be directed to this end.
Paper 28: Laminar Radial Flow between Parallel Plates and its Application to Viscosity Measurements
Authors: Moses John Ll.
Published: June 2010

To supplement viscosity measurements of water made by the more conventional methods, for example by capillary or rotating cylinder viscometers, it was decided to make a ‘radial flow viscometer’ as outlined by H. Gümbel in Barr's ‘Monograph of viscosity’ (1)†.

The radial flow viscometer consists principally of two flat discs separated by a known distance, the fluid being forced to flow radially inward and leaving the discs through a hole in the centre of one of the discs.

Before the method could be adopted, it was essential to devise a formula which would account for the inertia term in the equation of motion, since disregard of the inertia term would render the final equation inaccurate.

An equation has been developed from the Navier-Stokes equations, which gives a solution involving elliptic integrals.

An attempt is made to compare the above solution with the well-known creeping flow solution and with experimental results. Preliminary tests for varying flows and varying widths of separation of the discs have shown discrepancies of under 2 per cent between experimental and theoretical values.
Paper 8: Fixed-Direction Probes for Aerodynamic Measurements
Authors: Lewis W. E.
Published: June 2010

This paper reviews the problems of using null-yaw and fixed-direction, multi-hole probes for aerodynamic measurements. The preparation of calibration charts for the use of fixed-direction three-hole probes in two-dimensional flow regimes and for the use of their five-hole counterparts in three-dimensional flow systems is described. Some of the sources of error in the use of these types of probes are also discussed.

In an Appendix, numerical examples demonstrating the use of the calibration charts are discussed.

A novel type of probe, fitted with a rotating sting is described. This probe is being developed to combine the advantages of null-yaw and fixed-direction probes.