bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Simplified Analysis of Rolling Elliptical Contacts in the Elastic–Plastic Range
Authors: Yeung K W , Lingard S 
Published: February 2007

The paper presents an analysis of the deformations and stresses in the rolling contact of solids of revolution. The simplified model is based upon traction-free rolling and materials which are ideal elastic-plastic solids, but produces upper and lower bound solutions for groove formation and residual stress distributions which are realistic. Data for the three-dimensional problem are presented showing the process of cumulative deformation during a number of rolling cycles up to a steady state.
Design Study for a Low Heat Loss Version of the Dover Engine
Authors: Hay N , Watt P M , Ormerod M J , Burnett G P , Beesley P W , French B A 
Published: February 2007

The paper describes an analytical and hardware design study aimed at evolving a low heat loss version of a current turbocharged production diesel engine, the Ford Dover engine. The analytical approach was done using the Ford engine simulation program and aimed to establish whether reduction in heat loss would be advantageous for this particular engine. Various levels of insulation were assumed on the piston crown, the cylinder head and the cylinder liner, and the effect on power output and fuel economy was assessed. It was found that reduced heat loss could be implemented without any major design changes and would result in benefits in both power output and fuel economy. New pistons and alterations to the combustion space were then evolved and specified in detail to bring about the desired reduction in heat loss. Thermal analysis of these designs using finite element and other approaches confirmed their suitability. The paper describes the approach, the various stages in the development of the designs, their assessment, and the predicted performance of the proposed low heat loss Dover engine.
Research in the Automotive Industry
Authors: Rossi C E 
Published: February 2007

Industrial research as a source of technological innovation has acquired a central role in companies in the 1980s. Large manufacturing companies have been developing research systems made of structures co-ordinated with and complementary to one another, in an effort to achieve a rapid and proper flow of innovation. This paper discusses the research system of the Fiat Group, with special attention being paid to the inter-disciplinary, integrated research project developed by the Fiat Research Centre in co-operation with the ‘Progetto Finalizzato Trasporti’ drawn up by Consiglio Nazionale delle Richerche (CNR). Such a project implies the design and development of a research car aimed at becoming a reference for future projects for the energy saving cars to be produced in the 1990s.
Analysis of the Forces on a Nuclear Fuel Transport Flask in an Impact by a Train
Authors: Miles J C , Molyneaux T C K , Dowler H J 
Published: February 2007

The majority of fuel transport flask movements is on the public rail network and there has been concern over the possible consequences in the unlikely event of an accident involving a flask. To allay these concerns the Central Electricity Generating Board (CEGB) embarked on a programme of research into the behaviour of flasks in accidents culminating in the public demonstration of a train imapct in July 1984. The train crash demonstration was preceded by extensive analytical work directed at estimating the forces, effects and resulting motions of the primary impact. The mathematical modelling and analyses are described, with an earlier study of a high-speed train (HST) impact, and subsequent comparisons between the predictive estimates and the results of the demonstration. The impact effects expected and found are given in detail, with conclusions on the success of the estimating work and the relative severity of the IAEA (International Atomic Energy Agency) 9 m drop test compared with the train crash.
Tactile Sensors for Robot Handling
Authors: Foroughi F , Rahnejat H , Bera H 
Published: February 2007

First and second generation robots have been used cost effectively in high-volume ‘fixed’ or ‘hard’ automated manufacturing/assembly systems. They are ‘limited-ability’ devices using simple logic elements or primitive sensory feedback. However, in the unstructured environment of most manufacturing plants it is often necessary to locate, identify, orientate and position randomly presented components. Visual systems have been researched and developed to provide a coarse resolution outline of objects. More detailed and precise definition of parts is usually obtained by high resolution tactile sensing arrays. This paper reviews and discusses the current state of the art in tactile sensing.
Training in Advanced Engineering Design
Authors: Lickley Robert 
Published: February 2007

Engineering design and the education and training of more high-calibre engineering designers to ensure an increased flow of advanced technology, high-quality products from British shores, is becoming critical. This is recognized by an increasing number of top managements in industry, the Science and Engineering Research Council, Department of Trade and Industry and other leading bodies in the country. There is no doubt that comprehensive capable engineering designers cannot be produced solely from undergraduate courses and therefore urgent attention should be paid to establishing more postgraduate courses and other means of continuing education in advanced engineering design and development—including those which are project based—and to examine methods by which this might be achieved. A discussion meeting with invited senior participants, held at the Institution of Mechanical Engineers, London, and chaired by Sir Robert Lickley, is reported.
On the Computation of Inertial Coefficients in Squeeze-Film Bearings
Authors: Ramli M D , Ellis J , Roberts J B 
Published: February 2007

Inertial coefficients for full squeeze-film bearings are evaluated theoretically using Smith's differential equation relating fluid-film pressure to journal acceleration (1). The variations of the non-dimensionalized inertial coefficients with static eccentricity ratio in the radial and transverse directions are compared with some corresponding values obtained from Reinhardt and Lund (2) and Szeri et al. (3). The results from these three methods show good agreement, especially for short bearings (that is bearings with low values of length–diameter ratio). However, Smith's approach has the advantage of computational simplicity and leads to fairly simple, asymptotic, analytical expressions for very short, and very long, bearings.
Performance of an Electromagnetic Bearing for the Vibration Control of a Supercritical Shaft
Authors: Bradfield C D , Roberts J B , Karunendiran R 
Published: February 2007

The flexural vibrations of a rotating shaft, running through one or more critical speeds, can be reduced to an acceptably low level by applying suitable control forces at an intermediate span position. If electromagnets are used to produce the control forces then it is possible to implement a wide variety of control strategies. A test rig is described which includes a microprocessor-based controller, in which such strategies can be realized in terms of software-based algorithms. The electromagnet configuration and the method of stabilizing the electromagnet force–gap characteristic are discussed. The bounds on the performance of the system are defined. A simple control algorithm is outlined, where the control forces are proportional to the measured displacement and velocity at a single point on the shaft span; in this case the electromagnet behaves in a similar manner to that of a parallel combination of a linear spring and damper. Experimental and predicted performances of the system are compared, for this type of control, where various programmable rates of damping are applied.
Power Transmission Losses in V-Belt Drives Part 2: Effects of Small Pulley Radii
Authors: Childs T H C , Cowburn D 
Published: February 2007

Run-in AV10 wrapped, raw-edged and cogged V-belts have been used to transmit power between pulleys of equal radii R equal to 51, 36 and 21 mm. Separate measurements of the torque and angular speed losses between the pulleys have shown that these are approximately proportional to 1/R and 1/R2 respectively and are also greater than expected from current theories. The maximum useful belt tension ratio fell from 21 to 5 as R was reduced from 51 to 21 mm. A dimensionless belt deformation parameter (gEI/R4)1/2, arising from a simplified analysis of torque loss, has been found empirically to correlate with both torque loss and the speed loss in excess of that expected from belt extension and radial compliance. Subsidiary tests with thick flat belts on cylindrical pulleys have shown their power losses to be unexpectedly close to those of V-belts of similar cross-sectional area, suggesting that those V-belt losses usually attributed to wedging in the pulley groove are of more general origin. It is speculated that belt carcass warping or shearing distortions must be considered to explain losses on small-radii pulleys.
Comparison of Methods for the Calculation of Mass Fraction Burnt from Engine Pressure—Time Diagrams
Authors: Stone C R , Green-Armytage D I 
Published: February 2007

Calculations of the mass fraction burnt as a function of time in a spark ignition engine have been made by two methods. The simple method assumes that the mass fraction burnt is in proportion to the fraction of total pressure rise due to combustion. The complex method assumes a two-zone combustion model, and computes the mass fraction burnt that is required to give the observed pressure rise for each 1° crank angle increment. The complex model allows for dissociation, variable gas properties and heat transfer from the burnt and unburnt gases. Notwithstanding the substantial differences between the two models, the results are in surprisingly close agreement. This can be attributed to the fact that the temperature of the burnt gas remains nearly constant during combustion.
Danish State Railways Push-Pull Operation by Diesel and Electric Locomotives with Three-Phase Drive
Authors: Adelkvist V 
Published: February 2007

In 1973 the Danish State Railways (DSB) began regular push-pull train operations with diesel-electric locomotives on the east coast line between Copenhagen and Elsinore. The internal train control system was based on transmission via a two-wire transmission line extending through the train. The transmission of information through the train between a driving-trailer coach and one or two locomotives, was accomplished by a digital technique. The push-pull service was gradually extended and now comprises all lines on Zealand. In 1981 the new diesel-electric locomotives (class ME) with three-phase drive was put into push-pull service and 37 M E locomotives now perform the main part of the service (an average of 210000 km per locomotive per annum). The reasons for choosing three-phase locomotives, the experience gained with push-pull service, as well as the maintenance system and costs of maintaining three-phase drive locomotives in comparison with conventional diesel-electric locomotives are described. DSB is carrying out electrification (25 kV, 50 Hz) of all lines east of the Great Belt. The push-pull service with electric three-phase drive locomotives (class EA) commenced in March 1986. The advantages of choosing three-phase drive in connection with the introduction of electrification with a 25 kV, 50 Hz system are discussed. Class EA locomotives are equipped with a new generation of internal train control system based on a time multiplex system, which is able to transmit more information between locomotive and driving-trailer coach than the old system. Present experience regarding the push-pull service with class EA locomotives and the time multiplex control system is also described.
Co-Generation in Arid and Cool Climates: A New Unified Perspective Using Exergy Analysis
Authors: Barclay F J 
Published: February 2007

Co-generation plants are the norm in the arid climates of the Middle East, producing electricity and fresh water from the sea. In cool climates such as that of the United Kingdom combined heat and power, and district heating are under reappraisal. An attempt is made in the paper to use exergy theory to generate a new unified sense of proportion for these forms of co-generation. From the new perspective springs a realization of the benefits to network operation and investment which would flow from the development of a range of large vapour compressor heat pumps. Doubt is cast on a concept, in current use, known as the ‘fuel utilization’ or ‘energy efficiency’. In the Middle East the concept has distorted co-generation system operation theory and capital investment principles. In United Kingdom documentation an unjustified aura of efficiency is ascribed to district heating, and condensing plants are wrongly denigrated. The paper is an attempt to propagate ideas. Realization of those ideas is in the references or is deferred for later papers. It is important that qualitative thinking is correct before quantification begins.
Flameproof Diesel Engines in Underground Coalmines in Britain—design Features and Operational Experience
Authors: Currie J A N 
Published: February 2007

The use of flameproofed diesel engines in underground mines of the British coalmining industry has a history approaching fifty years. During that time, the design of the flameproof package has seen considerable changes, due both to normal evolutionary processes and to changes to statutory requirements, the most recent of which is the introduction of BS 6680 (1). This paper briefly reviews the design changes that have occurred and describes the design features of typical current units. Today's units are inevitably more complex than those which were first introduced, owing to more stringent safety requirements; this has an impact on reliability and maintenance which is discussed, along with general operational experience. The implications of the introduction of BS 6680 on future designs are also discussed, together with recent and current research and development aimed at reducing the size and cost of the flameproof unit.
Submarine Power Systems Using the V4-275R Stirling Engine
Authors: Nilsson H 
Published: February 2007

The Stirling power module V4-275R, integrated with a liquid oxygen system, is currently built for submarines for the Royal Swedish Navy and for the offshore company Comex in France. Since mid 1985 the Stirling engine system for the Swedish Navy has been successfully tested in a full-scale submarine test section. The next step in this programme will be an integration of the Stirling system into an operational Swedish submarine. A contract has been signed having Kockums as the main contractor. The French programme means a 500 ton manned diver lock-out submarine, the SAGA I, which is under final construction at Comex in Marseille. The energy system for the SAGA submarine consists of two V4–275R Stirling engines of maximum 100 kW power each. The oxygen storage, manufactured by AGA Cryo in Gothenburg, consists of two liquid oxygen tanks providing a total capacity of 10000 kWh, allowing the submarine to perform missions of up to 14 days submerged.
Training Placements for Sandwich Students in Small Companies: The Group Scheme for Technologist Industrial Training at Bradford University 1972–87
Authors: McArthur G M , Seale W J 
Published: February 2007

Group Schemes for technologist industrial training were established in the early 1970s on the initiative of the Engineering Industry Training Board (EITB) to help small companies to take sandwich course students for single periods of industrial training. The Group Scheme at Bradford University has provided industrial training places for 40 students on the mechanical engineering course during the last 15 years, and the participating companies have recruited six graduates. Details are given of the operation of the Scheme including recruitment, the provision of basic engineering training, and the response of small companies to changes in grant aid. The provision of grant aid has proved a critical factor in the readiness of a company to take a student. The introduction of Engineering Applications 1 (EAI) and changes in funding from the EITB has altered the Group Scheme from a body offering sponsorship in a collective of small companies to one providing closely monitored training for ‘college-based’ students. The work of the Group Scheme could be improved by giving the EITB responsibility for encouraging engineering training in all industries.
Training and Skills for Computer Aided Design and Draughting
Authors: Riley P , Hannam R G 
Published: February 2007

This paper presents and discusses the results of a survey of the training of users of computer aided design and draughting (CADD) systems. The survey sample was taken from selected companies using more sophisticated systems so that both the use and the training for use of a large range of software facilities were covered. As with any new technology, CADCAM systems have necessitated their users learning new skills and this has to be provided by training. Training for CADD has significant implications for both industry and academe. Industry is often criticized for failing to train adequately and academe is criticized for failing to prepare graduates for industry. What is the appropriate training for CADD system users and what aptitudes are desirable? How effectively is industry training its personnel and how far should undergraduates be given CADD skills? These and related questions are discussed with reference to the results of the survey.
Thermal Analysis of a Spur Gearbox Part 1: Steady State Finite Element Analysis
Authors: Joule D , Hinduja S , Ashton J N 
Published: February 2007

The accuracy of previously published thermal analyses of machine tools has been severely limited by imprecise thermal boundary conditions, in particular the values and distribution of heat inputs and heat-transfer coefficients. This paper describes an attempt to overcome some of the difficulties by determining the thermal boundary conditions for calculating the temperatures in a gearbox using the finite element method. A spur gearbox test rig has been designed and constructed, and a finite element model of the test gearbox developed. Temperature measurements and lubricant flow observations from experimental work have been combined with relevant theory to derive the boundary conditions. In the first part of this paper the experimental work and finite element steady state results are described. Sufficient agreement is evident between the two sets of results to indicate that the approach adopted here could be usefully extended to the analysis of other similar problems.
Forced Convection Air Cooling of an Array of Electronic Modules Using the Finite Element Method to Analyse Module Heat Transfer
Authors: Hardisty H , Abboud J , Vertman S 
Published: February 2007

Because of the current trend in manufacturing to pack a greater number of electronic components into a given volume, the thermal failure of microelectronic systems is becoming an increasingly difficult design problem. This paper describes heat-transfer research into the important case of air cooling by forced convection of an array of electronic modules on a printed circuit board (PCB). Because of the interrupted nature of the airflow over the surface and the complex three-dimensional nature of the heat flow path, theoretical analysis is difficult and heat-transfer data for design are relatively scarce. A research rig was designed and constructed which provided control of module power dissipation and continuously monitored the temperature of individual packages. An automatic data-acquisition system was successfully developed to record the large amount of experimental data that was generated. Realistic finite element models of the electronic package, leads and substrate were developed and used to reveal the temperature distribution. These models were also used, in conjunction with the experimental data, to determine heat-transfer coefficients. Correlations were established that related the value of the heat-transfer coefficient to distance from the leading edge of the PCB. It is intended that these correlations, together with the thermal analysis contained in the paper, will provide useful data for designers.
Two-Dimensional Elastohydrodynamic Lubrication Part 1: The Associated Dry Contact Problem
Authors: Hall R W , Savage M D 
Published: February 2007

Associated with each elastohydrodynamic (EHD) lubrication problem there is a dry contact problem with the same contact zone, |x| a, surface displacement, υ(x), and pressure distribution, p(x). This paper considers the two-dimensional dry contact problem and shows how Poritsky's closed-form solution can be used to derive results of fundamental importance to EHD lubrication. In particular, it is shown that singularities in pressure and pressure gradient arise from discontinuities in dυ/dx and d2υ/dx2. In addition, with υ(x) expressed as a Fourier cosine series of the form υ(x) = Σn Bn cos nη (where x = a cos η, 0 ≤ η ≤ π), it follows that at the end points of the contact zone, Reynolds boundary conditions are natural conditions yielding straightforward conditions on the Fourier coefficients, Bn.
Ideal Characteristics of a Variable Ratio Belt Drive
Authors: Bekircan S 
Published: February 2007

A fundamental theory concerning the theoretical power-torque envelopes over the speed ratio range of a general variable ratio belt drive is presented, to the best of the author's knowledge, for the first time. This theory applies to both V and flat belt drives, and is independent of the detailed designs. The analysis is based on two limiting factors, namely the maximum tension and the tendency of the belt to slip bodily on one or both pulleys assuming that the centre distance and the belt length are constant. These above factors determine the power and torque envelopes. The most suitable envelopes for the design purpose of the variable ratio belt drive are those of compact size, maximum belt tension and relatively high transmitted power.
Performance Predictions for a Pneumatic Active Car Suspension System
Authors: Sharp R S , Hassan J H 
Published: February 2007

A mathematical model of a pneumatic active car suspension system in a single wheel station form excited by realistic road roughness input is set up. The active control is exerted through a d.c. motor-driven air-pump. The model is used to show that essentially all the advantages of active control, within the terms of reference, are obtained by employing the control only at low frequencies and having the suspension parameters adapt to the running conditions as they vary. Control laws are derived using limited state feedback, linear stochastic optimal control theory and power consumption, and space requirements are evaluated. System performance is shown to be good in comparison with other known arrangements and encouragement for further work to extend the results is given.
Methane Combustion in Laminar Diffusion Flames
Authors: Abam D P S 
Published: February 2007

This paper is concerned with methane combustion in laminar diffusion flames. Data on methane concentration distributions in different diffusion flame geometries are correlated against a conserved scalar called mixture fraction. The correlation is used to determine a global methane combustion rate applicable in the rich to stoichiometric regions of laminar diffusion flames. The global rate is consistent with methane disappearance through the forward kinetic step: CH4 + H → CH3 + H2 with [H] equilibrated according to [Formula: see text] on the rich side. This equilibration results from the three-body reaction [Formula: see text] which is equilibrated in the region 1.1 ≤ φ ≤ 2.74, 1300 K ≤ T ≤ 2000 K. These results indicate that initial radical attack on the fuel molecule provides the rate-controlling step for methane combustion.