bluuebunny/crossref_metadata_2025_split huggingface dataset:
Third Paper: The Development and Test Data of the Lucas Direct Flame After-Burner
Authors: Clarke J. S. , Soltau J. P. 
Published: June 2010

In designing an after-burner it was decided to use the California emission test cycle since this was the only recognized test standard. It also gave a fair coverage result, but for British conditions a modified cycle with longer idling and 15 mile/h cruising periods was used. Experience in gas turbine design was invaluable in tackling this design problem. Modern American automobiles have carbon monoxide emissions of 1·5–4 per cent when measured over the standard test cycle, but on some European vehicles 3–5·5 per cent has been observed. The dimensions of the after-burner had to be restricted to the available space in cars, and designed as simply as possible. Prototypes were made and extensive testing carried out. Eventually a satisfactory unit was produced with good performance on the road. The reduction in pollution was very satisfactory and values for the Californian cold test procedure were 1·5 per cent carbon monoxide and 100 parts per million hydrocarbons.
The Use of Fuel Cells in Automobiles: Examination of the Problems Involved in the Motor and Transmission
Authors: Watson E. A. 
Published: June 2010

This paper examines the limitations that are imposed by the characteristics of an electric motor employed in a vehicle powered by fuel cells and having a performance comparable with a petrol- or diesel-engined vehicle of present-day design. It is not, in the first instance, intended to deal with the substitution of fuel cells for the storage battery on an electric truck. As a result of certain desirable characteristics, such as absence of fire risk, silence in operation, manoeuvrability, and ease of control, the battery-operated electric truck has already found a special market despite its relatively high cost of operation when due allowance is made for battery replacements. It cannot compete in any way, however, with the ordinary internal-combustion-engined vehicle for rapid transport over distances of 20 miles and more. The object of the paper is to consider what limitations may arise that are due to the characteristics of the electric motor even if the fuel cell is developed to the extent of becoming an extremely light and efficient unit.
A Theoretical Analysis of the Lateral Properties of Suspension Systems
Authors: Hales F. D. 
Published: June 2010

The suspension system of a vehicle interconnects its wheels and body and provides the means by which forces and movements are transferred from one to the other. The lateral properties of suspension systems are required for lateral handling and other suspension studies, and this paper contains a theoretical analysis of such properties for a range of suspension systems: viz. double wishbone, Macpherson strut, swing axle, beam axle, and beam axle-Panhard rod. The lateral motions of a wheel on a road, resulting from prescribed motions of the vehicle body, are derived for the range of suspension systems considered. Attention is concentrated on the two principal body motions of vertical and rolling velocity, and the resulting suspension movements are determined in terms of these suspension derivatives. In the case of the double wishbone suspension, the various types, each with differing characteristics, are distinguished. Regions are defined within which suspension systems will have certain properties, and the boundaries of these regions are determined. By a suitable choice of defining parameters, the Macpherson strut suspension is shown to be equivalent to a double wishbone suspension, and therefore the analysis of the double wishbone suspension is applicable to the Macpherson strut. By comparison with the double wishbone suspensions the remaining suspensions considered have only limited ability to vary their suspension characteristics. The effects of suspension design on the steady state roll angle, suspension jacking, and load transfer are investigated. A single end suspension is first considered, and the dependence of the roll angle and suspension jacking on the suspension derivatives is demonstrated. This dependence enables the significance of the various regions derived earlier to be stated. For the complete vehicle, the suspension derivatives again determine the roll angle, and in this case the wheel load transfers are also dependent, via the body transferred rolling moment, on the suspension derivatives. The suspension derivatives are required in handling studies and the method of analysis is capable of giving considerable insight into the general behaviour of suspension systems.
An Introduction to the Dynamic Properties of Vehicle Suspensions
Authors: Ellis J. R. 
Published: June 2010

While the general outline of vehicle suspension behaviour is fairly well known little interest has been shown in the detailed dynamic performance of the various designs. From such a study it is possible to predict the natural frequencies of the suspension systems and their response to various disturbances whether these are due to cornering forces, wind gusts or road disturbances. Initially some typical suspensions are considered using the equation of Lagrange. Body movements are considered to consist of vertical and lateral displacements together with rotation about a geometrically defined point, the instantaneous centre of roll. Wheel movements are controlled by the geometry of the particular suspension. The suspensions considered do not exhaust the subject but serve as a guide for the analysis of particular systems which may be required from time to time. The linearized equations of motion are given in matrix form, from which the natural frequencies of the system may be derived. No attempt is made to produce formulae for the natural frequencies since in practice it is more satisfactory to substitute numerical values for the symbols at this stage. Some of the differences between the tyre behaviour in static and rolling states are mentioned. This is of particular relevance in view of the development of extensive vehicle vibration test rigs.
Discussion in the United States of America on Some Experiences with a Differentially Supercharged Diesel Engine
Authors: Dawson J. G. , Hayward W. J. , Glamann P. W. 
Published: June 2010

The paper* Was first presented at an Ordinary Meeting of the Automobile Division of The Institution of Mechanical Engineers, at Headquarters, 1 Birdcage Walk, Westminster, London, S.W.I, on Tuesday, 14th April 1964. It was again presented at the S.A.E. National Powerplant Meeting, Baltimore, Maryland, U.S.A., on 20th October 1964, under the Chairmanship of Professor Philip S. Myers†. The discussion papers and the authors' reply which followed this second presentation of the paper were forwarded to the Institution by Professor P. S. Myers on 16th December 1964 and were approved for publication in this volume
Torsional Stiffness Analysis of Car Bodies
Authors: Cooke C. J. 
Published: June 2010

Expressions are provided for calculating the torsional stiffness of a car body passenger compartment. The two main reaction systems which contribute towards the torsional stiffness, i.e. the couple due to shear forces in the roof and floor and the rectangular frame formed by the sill torque boxes and the end bulkheads of the passenger compartment, are considered separately. This enables the behaviour to be studied qualitatively as well as quantitatively. It is shown theoretically and diagrammatically that the first system is dependent on the bend stiffness of the members forming the door apertures. Simplifying assumptions permit the expressions developed to be sufficiently straightforward for them to be acceptable for repeated use in the design office to optimize the distribution of material. Alternative approaches are suggested for cases where greater accuracy is necessary. The basic expressions relate to a simplified structure but a technique is supplied for assessing the contribution of extra members. The effect of the horizontal offset of the wheel centres from the ends of the passenger compartment is discussed and the influence of suspension and structure geometries on the effective offset is mentioned. Ways in which the deflections of the passenger compartment affect the front and rear end structures are discussed qualitatively.
Second Paper: Studies on the Skidding Resistance of Passenger-Car Tyres on Wet Surfaces
Authors: Maycock G. 
Published: June 2010

This paper reports investigations into the effect of tread pattern, pattern modifications, tread material and tyre casing construction, on the skidding resistance of passenger-car tyres at speeds between 25 and 80 mile/h on a range of wet road surfaces. The technique used was to brake the front wheels of a car until these wheels locked, and to record the resulting deceleration of the vehicle. From the deceleration record, both the peak and locked-wheel values of the braking force coefficients were obtained. The method is described and an assessment of the errors involved is given. The experiments showed the importance of adequate drainage of the region of contact between tyre and road, particularly at the higher speeds, in order to remove the lubricating film of water. Such drainage can be provided either by a tread pattern or a coarse road surface, and the present results indicate the importance of each and their inter-relation. The results of various modifications to a standard tread pattern are given; these show that on smooth surfaces worth-while increases in wet road adhesion at high speeds can be obtained by suitable design of tyre tread patterns. The magnitude of the increases in friction due to changes in tread material are given for both peak and locked-wheel coefficients. Ratios of peak to locked-wheel coefficients have been calculated over a wide range of surface and tyre combinations, and they show the potential value of devices enabling a vehicle to make use of these high coefficients.
Cooling Rates of Brake Drums and Discs
Authors: Newcomb T.P. , Millner N. 
Published: June 2010

An investigation has been made of the rates of cooling of vehicle brake drums and discs. Thermocouples were inserted in the drums and discs and in the wheel hubs and their outputs fed via slip ring units to meters mounted inside the vehicle. The drums or discs were heated to a uniform temperature of 300°-400°C by drag braking and the rate at which they cooled measured while the vehicle was driven at constant speed. Measurements were made at various speeds in the range 0 to 90 mile/h. From the log (temperature) against time plot a cooling coefficient bv was determined. It is shown that at a vehicle speed v the quantity bv can be expressed in the form bv = b0 +Kv0·8 where b0 represents the loss of heat to the hub and K is a constant depending on the size and shape of the drum or disc. Values of these constants have been determined on a variety of cars having discs and drums varying from 7 in to 11 in diameter and on a lorry fitted with 16·75 in diameter drums. Cooling rates are shown to depend on shape and size of the disc or drum. Results show that the cooling rates of front brakes are about 20 per cent higher than the rear brakes and that front discs cool about 25 per cent more quickly than the corresponding drum size recommended for the same vehicle. The cooling rate of front discs did not change when wire wheels were fitted instead of solid wheels. Ventilated discs and solid discs were also compared. The effect of fitting dust shields on disc brakes is shown to reduce the cooling rates by about 30 per cent. The effect of otherwise disturbing the air flow was studied.
Engine Cooling System Design and Development
Authors: Stratton D. G. , Stringer R. E. , Taylor S. R. G. 
Published: June 2010

Engine cooling is a complex multi-stage process of which only the latter stages, that of heat exchange between water and air, are considered. Cooling system performance targets as air temperature to boil values are indicated. The relationship between engine heat rejection to the coolant, radiator matrix specific dissipation and air temperature to boil is established in a form suitable for simple calculations. Measurement of cooling system quantities and performances of individual components requires suitable test rigs and a full size vehicle wind tunnel. Data acquired from such measurements provides the basis for the application of an analytical approach to the design and development of cooling systems to achieve given cooling performance targets in the most economical manner. A computer programme, capable of embracing the wide range of cooling system parameters, is seen as the most effective way of fully examining both new and alternative designs.
Second Paper: The Effects of Physical Factors on Ignition Delay
Authors: Lyn W-T. , Valdmanis E. 
Published: June 2010

The effects of physical factors on ignition delay have been studied on a motored research engine using a single injection technique. The fuels used included a high cetane number reference fuel, gas oil and M.T. 80 petrol. The primary factors investigated are those pertaining to the fuel spray, such as injection timing, quantity, and pressure (affecting drop size, velocity and injection rate); hole diameter (affecting drop size and injection rate) and spray form (nozzle type); and those pertaining to the engine, such as temperature, pressure and air velocity. Engine operating variables such as speed and load affect the ignition delay because they change the primary factors such as injection pressure, compression temperature, pressure and air velocity. It has been found that under normal running conditions, compression temperature and pressure are the major factors. All other factors have only secondary effects. Under starting conditions, when ignition is marginal, mixture formation becomes as important as compression temperature and pressure. Such factors as air velocity and spray form which affect the mixing pattern can have a very pronounced effect on ignition delay. Published data on ignition delay are compared with those obtained in the present investigation and a generalization of the data is recommended for engine design and computational work.
First Paper: Full-Scale Studies of the Performance of Plant in the Compaction of Soils and Granular Base Materials
Authors: Lewis W. A. 
Published: June 2010

The installation and test procedure employed at the Road Research Laboratory for studying the performance of compaction plant is described. The results of tests on a wide range of equipment are summarized and an outline is given of some investigations of more fundamental factors likely to affect the performance of compaction plant. The author would like to acknowledge the help given by his colleagues and particularly Mr A. W. Parsons of the Laboratory who assisted in much of the work described in the paper. The work described in this paper was carried out as part of the programme of research of the Road Research Laboratory and is contributed by permission of the Director of Road Research. Reproduced by permission of the Controller of H.M. Stationery Office, Crown copyright.
Second Paper: Meeting the Spark Plug Requirements of European Engines
Authors: Robson J. V. B. 
Published: June 2010

Modern engines and driving conditions have imposed serious problems on the spark plug designer. Colder or ‘harder’ spark plugs are now required yet they must resist cold fouling in city driving. These conditions are largely being met by spark plugs in which the insulator core nose protrudes beyond the steel shell. Design features are discussed and techniques for engine evaluation of spark plugs are described. If the spark plug temperature exceeds 950°C it is liable to become a source of pre-ignition though the actual pre-ignition temperature will depend on the fuel used. Transient pre-ignition from hot areas and deposits in the combustion chamber will increase the temperature of even very cold spark plugs and may force them into run-away pre-ignition. Detonation and the relationship of the spark plug to run-on are discussed. Improper installation and operation of ignition systems will precipitate apparent spark plug problems. Variations between identical engines may require careful investigation. Two-stroke engines have their own problems of pre-ignition and fouling and some are now operating on surface discharge spark plugs. Some require small size spark plugs. Racing engines and Wankel engines have particular requirements which do not necessarily relate to other engines.
The Use of Alternators on British Passenger Cars
Authors: Edwards L. E. , Winkley A. W. 
Published: June 2010

The need for generators of higher output ratings and improved performance at low engine speeds has resulted in the development and growing employment of alternators for battery charging systems on British passenger cars. This paper discusses some theoretical and practical problems in the specification, design and application of such alternators. Part 1 covers the method of assessing the ‘Effective Output’ of an alternator by means of engine time-speed histograms, and shows the way in which this effective output is influenced by the drive ratio of the alternator. Empirical rules are put forward for deciding the effective output needed for a car with given electrical loading, and correlation is shown to exist between the empirical assessment and the results of practical vehicle running tests. The manner in which the alternator characteristics can be modified by the designer within a given overall size of machine, and the influence upon the effective output of such changes, are discussed. Part 2 surveys the practical experience gained to date by the authors' company in the use of alternators on British passenger cars. The reasons leading to the present standard fixing arrangements for alternators arc described, together with suggested designs for the alternator mounting bracket which forms part of the engine. The different forms of noise emanating from an alternator are discussed. The practical implications of achieving the desirable drive ratios lead to the conclusion that improved performance of the conventional belt drive arrangement will become necessary. The paper concludes with some remarks on the philosophy of warning light indication, and describes some systems which meet the present requirements.
Optimum Stiffness-Weight Design of Peripheral and Ladder Frames
Authors: Sharman P. W. 
Published: June 2010

The equation for the torsional stiffness of a rigid jointed rectangular plane frame is given and non-dimensionalized to provide simple comparative criteria. The effect of extreme variation in member properties is discussed. Design charts for certain cases are given. It is shown that the equation may be modified for ladder frames of uniform spacing, under certain simplifying assumptions. The equations have been applied to model frames giving good agreement with experimentally determined values. The members are analysed in terms of their stiffness-weight ratios and the weight parameter is calculated for families of peripheral and ladder frames. For frames of the same torsional stiffness the optimum designs are then discussed. The effect of a constraint on minimum flexural stiffness on the optimum design of a ladder frame is discussed.
Run-on in Gasoline Engines
Authors: Affleck W. S. 
Published: June 2010

When the ignition of a car engine is switched off, the engine normally comes to rest within a few revolutions but, occasionally, it may continue to fire erratically for a few seconds or longer. This phenomenon is known as run-on and, for the majority of European engines, is the result of spontaneous ignition of the fuel-air mixture in the combustion chamber. Part 1 of this paper describes experiments in a single-cylinder research engine which have been made to establish the principles controlling run-on. In particular the effects of air/fuel ratio, the nature of the fuel and the pressure-temperature-time history of the fuel-air mixture in the combustion chamber have been studied, as it is known that these factors play an important part in spontaneous ignition in experiments in laboratory vessels. From these observations it has been possible to formulate a theoretical model of the run-on process which explains the salient features of the phenomenon. In particular, it shows how the gradual cooling of the engine limits the duration of run-on and also how the duration of run-on may be considered as a measure of the extent to which fuel or engine factors must be altered to eliminate run-on. Part 2 describes the application of these principles to car engines using normal commercial-type fuels. It is concluded that the following are important features in the control of run-on: the use of fuel of sufficiently high Research octane number, minimum opening of throttle at idle, sufficient time for cooling of the combustion chamber before the ignition is switched off, efficient engine cooling, and small valve overlap. Current devices for reducing exhaust emissions are likely, through their effects on these features, to increase the tendency of an engine run-on. Combustion chamber deposits, though, appear to have little influence.
A Rational Approach to the Aerodynamics of Engine Cooling System Design
Authors: Paish M. G. 
Published: June 2010

The aerodynamic inefficiencies of motor vehicle cooling systems are generally of secondary importance to their production costs. However, the advent of the inexpensive moulded fan has meant that an improvement in cooling system aerodynamics can be more readily achieved which could reduce costs and radiator sizes, with the additional benefits of predictable performance and improved economy. In the investigation described, the design objective was to meet the top gear cooling targets entirely with ram-induced airflow, and to design the engine driven fan so that it consumed negligible power for top gear conditions, whilst being capable of meeting the cooling targets in the intermediate gear ratios. The work divided itself into the following three sections: (1) The prediction and achievement of the maximum ram-induced airflows. (2) Designing the cooling fan to be effectively free-wheeling and, therefore, consuming negligible power during top gear motoring, and to measure the performance of the resulting fan throughout the ram and fan assisted airflow regimes. (3) Designing and predicting the performance of a cooling system which was subsequently built and installed in a test vehicle in order to check its performance and making an overall comparison with regard to the original system. The paper shows that the design objectives were closely achieved. The 1·7 litre test vehicle was cooled satisfactorily with a one foot square radiator with the expenditure of only 0·9 hp in the cooling system when travelling at 70 mile/h.
An Exercise in Steam Car Design
Authors: Palmer R. M. 
Published: June 2010

In recent years atmospheric pollution by the exhaust emissions of vehicles has become of increasing concern, particularly in America. One consequence of this has been a review of alternative power sources to the petrol engine, with the object of finding a suitable system with significantly lower quantities of toxic emission products. The merits of various possible systems have been amply discussed elsewhere and are not covered in this paper. Among others, the Rankine cycle engine using steam or other vapour has been put forward and indeed has many ardent supporters. It has been the subject of considerable publicity in the technical and popular press, for the most part extolling its virtues but seldom mentioning any vices.