bluuebunny/crossref_metadata_2025 huggingface dataset:
Paper 13: Cylinder Heads
Authors: Henshall S. H. , Gallois J.
Published: June 2010

Stresses in cylinder heads, gas loading, thermal loading, and tightening are dealt with in this paper.

The rigidity of heads, internal ribs, valve apertures, gas passages, and water passages are also referred to, as are different types of heads, e.g. two- and three-deck heads, heads with two or four valves, and heads without valves.

The effect on the design of heads of the cooling water route, connections, gaskets, and joints is also dealt with and some mention of materials, casting techniques, and coring of intricate passages is made.
Paper 3: The Design of a Space-Frame Crankcase for a Large Medium-Speed Diesel Engine
Authors: Morland G. W. , Flear B. S.
Published: June 2010

The basic arguments which led to the choice of a framed crankcase structure for a new range of in-line and Vee engines is described. The underlying principles behind the evolution of the actual design are discussed in relation to criteria for strength, stiffness, manufacturing procedure, and noise reduction.

The relative merits of underslung crankshaft and bedplate types of structure are discussed, and the programme of model and prototype testing which led, together with manufacturing considerations, to a decision between the two is described. Extensive model and prototype testing, in conjunction with theoretical analysis, was used as a major design tool and to prove the design. This is described in some detail and comparative results presented and discussed.
Paper 4: Analysis of Diesel Engine Structures with Special Reference to Traction Application
Authors: Briner M. J. , Borgeaud P.
Published: June 2010

To judge the quality and safety of an engine structure today it is almost indispensable to employ experimental stress analysis methods. Merely testing prototype engines for locomotive service does not offer adequate security with regard to the danger of fatigue in the structure. This applies particularly to welded designs, because the scattering in production quality is an important factor here. The appropriate use of modern investigation methods is described with a number of examples. The decisive thing is to co-ordinate and exploit the available resources in design, research, and production so that optimum effectiveness is attained.
Paper 14: Test Rigs for Engine Components
Authors: Nestorides E. J.
Published: June 2010

The paper sets out the basic principles and describes the main features of test rigs which are used for determining static and dynamic stresses and displacements, fatigue strength, and load-carrying capacity of various engine components subjected to mechanical and thermal loads. It also discusses the relative merits of test rigs and gives details of the instrumentation required with some rigs in order to indicate the results.
Paper 13: Arthroplasty of the Hip Using Foreign Materials: A History
Authors: Scales J. T.
Published: June 2010

Arthroplasty is a surgical procedure which provides an artificial joint. The operation should give ( a) relief from pain; ( b) a stable joint; and ( c) an improvement in function. The loss of function of a joint may be caused by injury or disease.

Since 1894 there have been many attempts to restore function using various artificial materials either to separate or replace the joint surfaces, and the following is a list of the ‘milestones’ in this field:

(1) The use of foils to cover the femoral head. (2) Floating joint interposition. (3) The introduction of cobalt–chromium alloy. (4) The replacement of the femoral head. (5) The use of acrylic and other plastics for implants. (6) The replacement of the acetabulum. (7) Total hip replacement. (8) The introduction of acrylic dental polymer to anchor components in bone.

This paper will discuss the various materials and devices which have been used, and some of the complications which consequently have occurred.
Research Report 8: Current Status of Joint Lubrication
Authors: Dintenfass L.
Published: June 2010

Properties of synovial fluid and cartilage are reviewed and some thought is given to the nature of joint lubrication. It does appear, at this stage, that neither the classical hydrodynamic theory of lubrication nor the boundary lubrication can permit an adequate description of the mechanism of joint lubrication; a possible solution lies in application of the elastohydrodynamic theory of lubrication, although this theory is not yet advanced enough to handle the total complexity of joint lubrication.

It is suggested that, in principle, joint lubrication depends on the existence of thixotropic and elastic (normal stress phenomenon) fluid between the articular surfaces, that the area of the load-carrying film depends on the elasticity and resiliency of cartilage, and that the latter shows most variable, time- and load-dependent rheological behaviour.

Pathological changes in synovial fluid leading to the change of its rheology to Newtonian, will result in a damage to the articular surfaces; on the other hand, a presence of a healthy synovial fluid per se is not sufficient to maintain an efficient lubrication. Resiliency of cartilage is responsible for the existence of elastohydrodynamic conditions; a degeneration of cartilage will lead to boundary lubrication and mechano-chemical degradation of synovial fluid.

Complexity of the problems requires multi-disciplinary collaboration.
Paper 9: University Courses in Departments of Mechanical Engineering
Authors: Leah A. S.
Published: June 2010

The general aims in planning university courses are first considered in relation to the known needs of mechanical engineers. Thereafter, the recruitment of students is discussed at some length with special emphasis on the possibilities of obtaining more candidates. Pre-entry requirements, both academic and practical, are dealt with and this is followed by a look at the general structure of courses. A typical three-year course is next described in some detail, variants in different universities being mentioned. Finally some ideas on the possible future lines of development are given, the conclusion being that the scientific content must be counterbalanced by a correct proportion of design and production courses.
Paper 8: One-Year Post-Graduate Courses in Universities
Authors: Bannister F. K.
Published: June 2010

After a short historical introduction, the various kinds of formal post-graduate courses in mechanical engineering are briefly surveyed. These range from the short course of one or two days to the full-scale graduate course of 12 months or thereabouts and assessment is made of their respective suitabilities for different purposes.

The main emphasis in this paper is placed on the 12-month M.Sc. course and a variety of organizational and educational aspects of this type of course are considered. They include: (1) the problem of the initial assimilation into a common course of students of varying ages, industrial experience, and academic freshness; (2) the inclusion of project work in a basically formal course; (3) the possibility of subdividing the 12-month period into a number of shorter periods in order to facilitate the release of staff from industry; (4) the desirable proportion of overseas students in a course; (5) the relationship between a graduate course and the research activities of a department.

Connections with, and support from, industry are considered, as is the influence of S.R.C. Studentships on recruitment. The Robbins Committee recommendations on advanced formal courses are reviewed, and their effect on the growth in numbers of such courses is considered. Comment is made on certain implications of the Arthur Report and the probable future development of one-year post-graduate courses is discussed.
Paper 11: Training for Management
Authors: Turner B. T.
Published: June 2010

The paper emphasizes the importance of management in engineering and states the need for formalized education and training in management today. The content of some of the courses, seminars, and conferences covered at the English Electric Staff Training Centre at Dunchurch is then discussed together with some of the projects and exercises used. Some of the difficulties of running such a centre and ascertaining the real training needs are then mentioned. The importance of evaluation on a proper feedback basis by the use of management-by-objectives principles is also considered.
Paper 10: Steam-Piping Installations
Authors: Dimmock D.
Published: June 2010

This paper is intended to be of a practical nature and deals with the various aspects and problems which require to be considered and dealt with by a project engineer responsible for the layout, design, and engineering of a main steam piping system.

Two types of installation are considered:

(a) Main steam piping for power station plants operating within a temperature range of 482°C (900°F) and 568°C (1055°F), and (b) Long steam distribution lines operating up to a temperature of 468°C (875°F).

Although many of the problems are common to both types of installation such as pressure drops, terminal reactions on plant, expansion, layout, etc., these in both cases are discussed and procedures proposed for the preliminary and final stages of design, in order to arrive at a reliable and economic installation.

The necessity of preliminary and final detailed analysis is shown and the importance of considering the various types of supports, guides, and restraints in conjunction with this work.

Other features dealt with are the drainage of steam lines, cleanliness during erection, clean service conditions, lagging, and their contribution to satisfactory operation of the piping systems.
Paper 8: Maintenance Planning Applied to Plant Auxiliaries in the Central Electricity Generating Board
Authors: Wright V. J. , Seymour R. E. , Norris N. D.
Published: June 2010

The C.E.G.B. operates 230 power stations of various ages and output capacities representing a total capital investment of some £2400 million. The steam conditions, sizes of generating units, and complexity of the installed plant reflect the stage of technical development at the time of their construction. These factors influence the cost of production at individual stations as also do the nature and cost of fuel.

The economic level of maintenance at each station is thus dependent upon a number of factors and must generally be established locally. This places an obligation on the maintenance engineer to collect and consider economic, in addition to technical, data. Also, service experience must be fed back to the design engineer so that future plant designs may be improved. Unless a simple and effective control system is employed paper work can become an intolerable burden.

Power station maintenance can be broadly divided between:

(1) work which can only be carried out while a generating unit is shut down; (2) work which can be carried out with the main plant on load.

The first category has received the greatest attention, since the cost of keeping a modern generator out of service can be substantial. Planning of this work is based on Critical Path Analysis techniques which are now well known and widely practised.

However, the day-to-day maintenance of a large variety of auxiliary plant also presents a heavy planning burden upon the maintenance department. The basic minimum requirements for the effective local control of this work have been examined, while the most economic methods of:

(a) co-ordinating maintenance in a number of stations in the best national interest, and (b) ensuring that service experience is fed back to design engineers

are also receiving attention.
Paper 4: An Experimental Study of the Frictional Behaviour of Steels at Elevated Temperatures
Authors: Mitchell L. A. , Crawford T. S.
Published: June 2010

Many investigators, by the manner of presentation of results, have implied that for any given material combination and atmosphere, the coefficient of friction is a function of temperature alone. Experiments are described which were designed to evaluate the importance of the sliding and temperature histories on the unlubricated sliding performance of steels at temperatures up to 500°C. Only for a hardened steel, when mild wear prevailed, was the specimen history unimportant, and, in this case, μ was virtually independent of temperature. With materials exhibiting severe wear, sliding produced changes in friction which were attributed to hardening of the surfaces and when the thickness of oxide films became comparable with the size of transferred particles, exposure to temperature could modify subsequent frictional behaviour.
Paper 13: Fatigue Cracks of Bearing Metals Caused by Reciprocating Rubbing
Authors: Hirano F. , Goto S.
Published: June 2010

The authors carried out an experimental investigation on the fatigue failure of engine bearings by means of a combination of a slider and bearing metal on a reciprocating bed. Cracks were generated under the condition of mixed lubrication in the vicinity of the contact areas at the stroke ends of the reciprocating bed, where the friction force abruptly increased and reversed its direction. A unique relation similar to the usual fatigue curve was obtained by plotting the friction force against the cycles to failure in place of normal load. The conclusion was further confirmed by an experiment using another testing machine generating an alternating tangent force without sliding.
Paper 17: Study of Sintered Carbides and Surface-Treated Materials for Unlubricated and Elevated Temperature Rolling Elements
Authors: Scott D. , Blackwell J.
Published: June 2010

Materials and surface treatments potentially suitable for unlubricated and elevated temperature rolling bearings have been compared, wear resistance being assessed by loss of weight under unlubricated conditions. Tungsten carbide was superior to other materials tested. Grain size of the tungsten carbide and the amount of matrix material can have a considerable effect on performance. Use of solid film lubricants can eliminate or reduce wear. Soft nitriding can also be beneficial.

Metallurgical investigations of some selected failed specimens have been carried out.
Paper 14: Hydrodynamic Lubrication of Lightly Loaded Finite Cylinders
Authors: Boness R. J.
Published: June 2010

Theoretical results of the load-carrying capacity of lightly loaded finite cylinders indicate that the effect of side leakage can be secondary to upstream boundary condition considerations. Neglecting side leakage the calculations are extended to cover the experimental results of Crook into the régime where the fluid properties are pressure dependent.

The results support the adoption of the new velocity and velocity gradient boundary conditions suggested by Lauder.
Paper 15: Thermal Aspects of Hydrodynamic Journal Bearing Performance at High Speeds
Authors: Woolacott R. G. , Cooke W. L.
Published: June 2010

This paper describes a rig for testing journal bearings at high speeds under steady loads and reports on measurements of bearing and lubricant temperatures and lubricant flow-rates for hydrodynamic journal bearings operating at speeds up to 35 000 rev/min and mean bearing pressures up to 3333 lbf/in2.

Variations of temperature and flow-rate with load, speed, oil-inlet temperature and pressure, clearance, and oil-inlet grooving are also described, and the effects of bearing and lubricant temperatures on bearing performance are discussed.
Paper 26: Variability with Time of Bearing Clearance Due to Temperature and Pressure
Authors: Czeguhn K.
Published: June 2010

A method of calculation is described which allows the effects in time of temperature and pressure on bearing clearances to be investigated. The method is based on the fundamental hydrodynamic equation, the Fourier heat conduction equation, and the thermo-elastic equations, and combines these in a suitable manner. The iterative-numerical treatment of the calculations allows characteristic quantities, such as the revolutions per minute, to be altered during the course of the calculation. In order to simplify the calculations, an infinitely long bearing with lemon-shaped clearance and a centrally running shaft is assumed. This does not imply any limitation to the general applicability of the method, but merely serves as a means of reducing the effort required for the calculation work.
Paper 2: Development of a High-Speed Linear Bearing for Catapults
Authors: Mitchell C. C. , Buesnel F. J.
Published: June 2010

This paper is concerned with the experimental development of a linear bearing to take the launch uploads in the aircraft-launching steam catapult. The bearing employs a form of Michell tilting pad running on a continuous bearing strip and operates satisfactorily at bearing pressures of the order of 1250 lb/in2. Oil is supplied to the pads by a friction-wheel-driven gear pump. Pad life in service is limited by the starting conditions at commencement of launch.
Paper 8: Side-Leakage Factors for a Rigid Cylinder Lubricated by an Isoviscous Fluid
Authors: Dowson D. , Whomes T. L.
Published: June 2010

Many lubricated machine contacts can be represented by cylindrical surfaces, and some of these contacts such as gears and rolling contact bearings have been studied extensively in recent years within the developing subject of elastohydrodynamic lubrication. When high loads are carried by the contact, side leakage is of little importance, but there is little evidence to indicate the quantitative importance of side leakage when the loads are light. This question has assumed greater importance with the recent recognition that many nominally parallel surface thrust bearings rely upon thermal distortion for their effective load-carrying capacity, since the deformed shape can be approximated by a pad of cylindrical form.

In this paper solutions of the Reynolds equation are presented for the geometry of a cylinder near a plane lubricated by an isoviscous fluid. The resulting pressure distribution has been integrated to yield normal and tangential surface force components and the results are presented in the form of side-leakage factors to be used with the Martin solution for an infinite cylinder. The approximate ‘short-cylinder’ theory is presented and compared with the full computer solutions. The results are applied to two lubricated contact situations.
Paper 3: Lubrication of Rollers with Oils Containing Polymers
Authors: Hamilton G. M. , Robertson W. G.
Published: June 2010

The shear stresses in an elastohydrodynamic oil film have been calculated. In the inlet region they are of the order of 107 and in the outlet 109 dyn/cm2. While such stresses do not affect mineral oils they are liable to cause breakdown of polymers in multigrade oils. To test this film thickness measurements were carried out in a four-disc machine with a range of polymer solutions. It was found that the degree of viscosity loss varied greatly; some polymer solutions showed no loss whilst others merely exhibited their base oil viscosity. By measuring the viscosity of samples scraped from the disc surfaces it was possible to divide the observed viscosity loss into permanent and temporary components.
Lecture 1: The Contribution of the Physicist to Tribology
Authors: Tabor D.
Published: June 2010

These comments may be summarized in the following terms: the contribution that the physicist can make to tribology will be greatly increased by effective and enlightened collaboration with the chemist, metallurgist and engineer. In this work they will all need refined equipment. But, taking the longer view, men and ideas may well prove to be more important than machines and computers.
Paper 11: Lubrication of Involute Gearing
Authors: Kelley B. W. , Lemanski A. J.
Published: June 2010

This paper appraises the last ten years' work in the field of gear lubrication. The problems associated with the application of the critical temperature hypothesis to lubricant failure are discussed. Engineering characteristics of extreme-pressure lubricants are defined and illustrated.
Paper 22: Soft-Metal Bearings
Authors: Forrester P. G.
Published: June 2010

The rapid increase in the use of aluminium-alloy bearings is the most important development in soft-metal bearings over the last ten years. The context of this development is outlined, and reference made to other developments of high potential, notably oxide dispersion hardened tin, and metal-plastic composites.
Paper 23: Hard Materials
Authors: Scott D.
Published: June 2010

The present state of knowledge of methods of hardening and of strengthening materials and the use of hard materials for tribological applications is summarized. The essential properties of materials for various types of mechanisms such as rolling bearings, gears, cams, etc. are reviewed. Mechanisms of failure and controlling factors are discussed.
Paper 35: Selection of Bearings
Authors: Neale M. J.
Published: June 2010

The basic function of a bearing is to allow relative movement to occur between load-carrying surfaces, and there are various types available working on principles such as rubbing contact, rolling elements, fluid films, deflecting members and magnetic repulsion. The relationship between the allowable load and the speed for the various bearing types is compared with the way in which bearing loads change during the operation of variable speed machines. Various applications have also been studied to assess what bearing loads and rotational speeds would be expected in machines of different sizes. The information presented is intended to assist designers with bearing selection.
Paper 3: The Assessment of Vehicle Ride and Handling
Authors: Hales F. D. , Barter N. F. , Oliver R. J.
Published: June 2010

The paper deals primarily with MIRA's contribution in the areas of vehicle ride and handling. Vehicle ride and handling are defined in broad terms to delineate the areas under consideration, ride being concerned with passenger reaction, and handling with the driver-vehicle relationship. The most difficult problem of all ride and handling studies is considered to be the human subject since human variability, adaptability, sensitivity and absence of a fixed scale of values render study in the simpler engineering senses difficult.

Instrumentation systems used in the measurement of vehicle ride and handling studies are considered in a general way. A typical ride instrumentation system is illustrated.

Assessment of vehicle ride is considered under two headings, subjective and objective. The methods for subjective assessment of stimuli are discussed and as an illustration of the techniques involved the design of a subjective ride experiment is given. Brief details of the objective measurement technique and the ways of analysing the subsequent data are presented, and typical spectra obtained from the data analysis are shown. The correlation between the subjective and objective results is discussed.

Objective assessment of vehicle handling is considered in some detail. The ways of determining steady state behaviour based on the under/over-steer concept are detailed. The use of a tethered testing technique to overcome difficulties of steady state testing while braking and under limiting adhesion conditions is outlined. Assessment of handling under transient conditions is investigated by means of step input and frequency response tests. Typical results are used to illustrate vehicle behaviour.

Further ride work and subjective assessment of handling are briefly discussed, as are probable future techniques that may be used in the assessment of vehicle ride and handling.
Paper 9: Measurement of Vehicle Characteristics for Ride and Handling
Authors: Ellis J. R. , Sharp R. S.
Published: June 2010

The paper describes some apparatus which has been developed to measure those characteristics which are of interest in vehicle ride and handling. These are:

Vertical, lateral and fore-and-aft tyre stiffnesses and damper characteristics. Suspension spring rates and friction, suspension geometry and suspension roll stiffnesses. Steering gear geometry and dynamic characteristics, moments and products of inertia of the vehicle and vibration characteristics of the seats.

Some relevant theory and sample results are included in the Appendices.
Paper 11: Testing Automobile Components
Authors: Love R. J.
Published: June 2010

Test procedures on components fall generally into four categories: ( a) overcoming service troubles; (6) design studies; ( c) acceptance testing; ( d) quality control. Some tests may be undertaken in complete vehicles, but the use of special test rigs, in which components can be tested in isolation, offers a number of advantages. Rig tests are generally a compromise between simplicity and realism. It is important to be able to reproduce the type of deterioration which occurs in service, and the study of service failures is helpful. Measurements of service loadings and environmental influences are in many cases desirable, and where examples of service failure are not available, these measurements are essential.

Most laboratory tests merely indicate, with some approximation, whether one component is better than another, and it is usually not possible to determine confidently whether a component is suitable for service. To maintain a high level of reliability in components in service, coupled with efficient design, it is necessary to introduce more realism, both in laboratory tests and proving ground tests. This is being done to a limited extent, and a method is also available for relating both proving ground performance and laboratory performance to behaviour in service. Much more needs to be done to establish the most suitable techniques.
Paper 13: The Magnetic Tape Control of Engine Test Beds
Authors: Harris W. J.
Published: June 2010

A 4-channel magnetic tape recorder is used to collect data from the vehicle under test during actual test conditions. Recordings of engine speed, engine load and generator system load are transferred to a 14-channel tape recorder and used to automatically programme up to three engines mounted on test beds in the laboratory.

The techniques of recording and replaying the engine test data are described.
Paper 14: Gas Flow Passages in Nuclear Reactors
Authors: Lewis W. E. , Holmes M. J.
Published: June 2010

The design of flow passages for gas-cooled nuclear reactors is complicated by considerations of nuclear physics and structural design. This paper outlines these difficulties and describes experimental work aimed at establishing design criteria for complex ducts of particular shapes. The results concerning the effects of turning vanes and increasing duct width show that conventional procedures for reducing pressure losses in individual bends are not always successful in complex ducts.
Paper 16: The Performance of Annular Diffusers
Authors: Stevens S. J.
Published: June 2010

Tests have been carried out to investigate the influence of inlet conditions on the performance of symmetrical annular diffusers having 4:1 area ratio and 2·5° and 5° wall angles. The conditions at inlet were varied by using either approach lengths or annular gauzes. Tests on the 2·5° diffuser showed that the ‘efficiency’ deteriorated with increase in outer wall momentum thickness. In addition to the overall performance characteristics a detailed study has been made of the boundary layer growth in the 5° diffuser.

A theoretical analysis, based on the assumption of power law velocity profiles, of the flow in conical and annular diffusers operating with fully developed flow at inlet, has been carried out. While it is necessary to estimate the loss in stagnation pressure along the streamline of maximum velocity, the method does not require the use of an empirical auxiliary equation for the variation of the shape parameter. Comparison with experimental data shows good agreement for the point of separation and the axial static pressure distribution.
Paper 13: The Building—A Climatic Modifier
Authors: Hardy A. C. , O'Sullivan P. E.
Published: June 2010

The authors first introduce the concept of the climatic modification characteristic of a building and discuss on what factors this concept depends. The high climatic modification characteristic of traditional methods of constructions is briefly described, and the reasons for the reduced climatic modification characteristic of post-war buildings are investigated. Finally, the implications of considering the climatic modification characteristic of a building as a method of design in terms of building form, method of illumination, and heating and cooling load are discussed in some detail, supported by the results of some of the authors' recent research work.
Paper 11: Gaseous Fuel Installations
Authors: Sherratt A. F. C.
Published: June 2010

This paper investigates the reasons for the changing face of the gas industry and discusses the wide range of installations utilizing gaseous fuel for space and comfort heating. The gaseous fuels available in the U.K. are examined and the fundamental principles of combustion and control and the safeguards incorporated in appliances are outlined. The problems of conversion from town gas to natural gas are also dealt with. The main part of the paper is a review of types of gas installation used for space heating and cooling. Domestic, commercial and industrial installations and district heating are dealt with separately and the engineering and design details are given, supported by extensive references. Particular reference is made to installations peculiar to gas. The paper suggests a promising future for gas, and an attempt is made to indicate future trends in utilization and fuel costs.
Paper 15: Practices in the Commercial Field
Authors: Dale K. W.
Published: June 2010

The paper deals with the established methods of heating and ventilating which are used in commercial buildings. It discusses the changes in building design and use which limit the extent to which heating and ventilation alone can be employed if comfort conditions are to be maintained throughout the year. Modern building design makes it practically essential to provide air conditioning. Whichever method of heating, ventilating, or air conditioning is used, it must be decided upon as early as possible so that sufficient cost can be allowed and the building can be designed to keep capital and operating costs to a minimum.
Paper 4: Controls for Low-Pressure Hot-Water Heating
Authors: Porges F.
Published: June 2010

The paper describes modulating control for low-pressure hot-water systems. Compensators and mixing valves are described, and their advantages and disadvantages discussed.

The use of time switches is described and typical programmes given. Frost-protection devices for overriding time switches are reviewed, and a strong plea is made for greater simplicity.

Difficulties which can arise from faulty positioning of thermostats are discussed. Thermostats detecting lower temperatures than they are intended to can cause safety devices to shut the plant down unnecessarily, and examples are given of such occurrences.

Heat retained in the boiler refractories can cause the water temperature to go on rising after the burner has shut off. A heat balance is drawn up and suggestions made for preventing this phenomenon from operating high-temperature safety devices.

The difficulties of sequence control of two or more boilers in parallel are discussed. It is difficult to find a method of detecting part load which does not make the boilers hunt; this problem is discussed and a solution for one particular case is offered.
Paper 10: A Survey of Ventilation System Noise in Lecture Rooms
Authors: Richards E. J. , Dunmore J. H. , Croome D. J.
Published: June 2010

A survey has been carried out in 72 lecture rooms to investigate the effect of ventilation system noise. In many cases the systems have to operate at reduced speeds to permit tolerable noise levels and the reduced air volume results in the rooms becoming overheated. A lack of knowledge among architects and consultants, a misapprehension about the cost of providing sound control and the non-specification of acoustic standards appear to be the main reasons for this trend. This paper presents details of the characteristics of ventilation system noise and also suggests proposals for future work which will cover the acoustics of high-velocity air conditioning systems.
Paper 16: Education in Architectural Environmental Engineering and Design
Authors: Scott D. R.
Published: June 2010

Present use of the term environmental engineering is examined, and the limits of architectural engineering are defined. Attention is drawn to the difficulties of the construction industry arising from lack of co-ordination between specialists, both at the design stages and on site. Educational developments with the aim of improving the situation are described, including first degree courses in Environmental Engineering at Liverpool and Strathclyde Universities, an M.Sc. course at Bristol, and a proposed C.N.A.A. Honours degree course at the National College. Stress is laid on joint project training, and the need for students from different but allied disciplines to come together at the conceptual stage of a design. What they necessarily do as professional men as members of a design team must begin at student level. Finally, examples are given of the modern trend towards greater academic integration.
Review Paper 1: Surface Measurement
Authors: Greenwood J. A.
Published: June 2010

This review paper considers the various measures of surface roughness such as mean slope, mean curvature, bearing area curve, and the density of peaks which are needed to supplement the usual c.l.a. roughness value. The problems of using a stylus instrument are discussed, and different electronic systems for processing the output signal are outlined. The emphasis throughout is not on surface measurement as such, but on surface measurement in tribology.
Report 9: Measurement of Transient Surface Temperatures in Metal Cutting
Authors: Braiden P. M.
Published: June 2010

This report is concerned with measuring the varying thermal stresses in a metal-cutting tool, due to the temperature variations occurring at the tool-chip interface, in the course of intermittent cutting operations. During cutting, the tool is rapidly heated, developing compressive thermal stresses in addition to the mechanical stresses due to the cutting action, but during the non-cutting, or cooling, part of the cycle these latter stresses are absent, and a tensile stress develops on the tool surface. It is believed that these rapidly alternating stresses lead to tool failure by eventual chipping of the cutting edge.

The temperature at the interface is measured by means of the tool-work thermocouple technique, in which a tungsten carbide cutting tool contacts a steel workpiece, thereby forming the hot junction of a thermocouple system.

The technique is well established for temperature measurements during continuous cutting operations, but care must be taken if it is to provide reliable results. The extension of the technique to include intermittent processes is described, and results are shown for processes having a frequency of 15 c/s. Cutting times as small as 0·026 s have been used and temperature records for this, and greater cutting times, are presented.

A disadvantage of this method is that a temperature record is obtained only whilst the tool and work are in contact, and a method to overcome this is outlined.
Report 23: Considerations in the Design of Plain Sliding Test Rigs
Authors: Earles S. W. E. , Powell D. G.
Published: June 2010

After outlining the relative merits of rig-testing of materials compared with testing in situ the fundamental considerations in the design of the testing machine are discussed. Of basic importance is a realistic appraisal of the conditions under which the material is to be used and the subsequent incorporation of accurately simulated conditions in the experimental rig. In particular the thermal resistances in the rig should be approximately proportional to those existing in the proposed application. The paper outlines ways of measuring normal force, frictional force and wear rates and emphasizes the need to record some variables continuously.
Report 25: Evaluation of Lubricity
Authors: Pannett D. J. , Cameron A.
Published: June 2010

The effect of adding rape oil to mineral oil in a compounded axle-box lubricant was investigated, using critical temperature, friction, voltage discharge, and electrical resistance. The critical temperature was measured in a Bowden-Leben machine. The other quantities were determined by using a 1-in steel ball rubbing against 3 planes in a micro cup.

All these methods gave compatible results.
Report 27: Some Rigs for Investigating the Properties of Self-Lubricated Bearing Materials with Reciprocating and Oscillating Motion
Authors: Sheppard P. F. , Crump W. J. J.
Published: June 2010

Self-lubricated bearing materials find many of their applications in bearings with peculiar motions which will not support a hydrodynamic film. With motions other than continuous rotation or continuous sliding very little information is available. To provide these data for the designer and to investigate the suitability of these materials for specific duties several special test rigs have been developed.

This report describes some of the rigs developed for this work and the relevance of the results to field experience. The rigs are capable of subjecting the test bearings to a wide range of speeds and load with reciprocating, oscillating and semi-rotary motions in atmospheres of controlled humidity. Results are usually based on attained life, but both wear and friction are measured.
Report 28: A Low-Shear-Rate Viscometer for Use at Pressures up to 120 000 Lb/In2
Authors: Galvin G. D. , Jones B. , Naylor H.
Published: June 2010

As the first part of a programme in which the properties of lubricants under conditions encountered in the elastohydrodynamic régime will be measured, a low-shear-rate viscometer operating at pressures up to 120 000 lb/in2 has been constructed. It is of the falling body type in which the time of fall under gravity of a hemispherically ended cylindrical sinker through the test fluid is measured.

The relationship between viscosity and fall time is of the form:

A major correction is applied for the effect of pressure on the density of the fluid and a smaller one for the changes in dimensions of the viscometer under pressure. A means of measuring the change of density of the fluid is incorporated in the viscometer.
Paper 2: Experiments on a Model Simulating Heat Transfer between the Inlet Valve of a Reciprocating Engine and the Entering Stream
Authors: Annand W. J. D.
Published: June 2010

The experiments described in this paper are intended to show the approximate magnitude of heat transfer rates between a poppet-type inlet valve and the fluid flowing through it. A model inlet valve, containing an electric heating element, was placed in a short, straight, concentric duct and discharged into a larger, concentric cylinder. Heat transfer rate measurements suggest an increase of Nusselt number proportionate to the 0·6 power of the Reynolds number—the constant of proportionality depending on the valve lift. Calculations show that the effect of this heat transfer on volumetric efficiency is no more than 1 or 2 per cent, and the effect on the temperature reached by an inlet valve in a running engine is also of minor importance compared with those of heat transfer from the gases in the cylinder and of conduction to the seat and guide.
Paper 12: The Development of an Apparatus to Measure the Normal Emissivity of Small Plane Samples in a Controlled Atmosphere
Authors: Furber B. N. , Broderick R.
Published: June 2010

The heat transfer from fuel elements in magnox reactors under all normal conditions is predominantly by forced convection. However, in safety assessments a burst in a bottom main coolant duct is postulated, a reversal of the carbon dioxide coolant flow takes place, and heat transfer from the fuel elements at this instant could be by radiation only. The effective emissivity of the fuel element or the normal emissivity of plane specimens of fuel element material and a geometrical factor are therefore required to enable the maximum fuel element temperature to be determined.

The paper is mainly concerned with the development and calibration of an apparatus suitable for measuring the normal emissivity of small plane samples at temperatures up to 650°C. Though the design of the apparatus has been influenced by the special requirements involved in testing magnox specimens, the apparatus has a general application and the normal emissivities of other materials are also given.
Paper 21: A Quasi-Steady Flow Representation of Centrifugal Compressor Performance Characteristics in Non-Steady Flow Systems
Authors: Benson R. S. , Whitfield A.
Published: June 2010

This paper describes a theoretical and experimental study of the non-steady flow performance of a centrifugal compressor. The experimental work was designed to study the effect of pulse frequency on the compressor performance, for a given delivery configuration, using a rotary valve pulse generator. The experimental rig was designed so that it was possible to study the reverse flow and the pressure pulsations in the suction side of the compressor. The objective of the investigation was to discover how the compressor performance deteriorated with pulse frequency, and also to determine the frequency at which reverse flow through the compressor first occurred.

The objective of the theoretical work was to predict the onset of reverse flow through the compressor and the mean and transient delivery pressure ratio using the conventional stationary pipe non-steady solutions by the method of characteristics. The compressor unit was replaced by a boundary condition within the pipe system equal to the experimentally known steady flow characteristics of the compressor. The physical size of the compressor was replaced by an equivalent pipe length; this technique is described. The theoretical results are compared with an extensive series of experimental results. This work is a direct extension of that given in reference (3).
Paper 23: An Investigation of the Losses in the Rotor of a Radial Flow Gas Turbine at Zero Incidence under Conditions of Steady Flow
Authors: Benson R. S. , Cartwright W. G. , Das S. K.
Published: June 2010

The performance of a radial flow turbine, operating on compressed air, is measured over a range of pressure ratio and speed. Separate tests on the nozzle assembly alone enable the rotor performance to be separated from the overall characteristics. In particular, the conditions at each pressure ratio for which the nozzle exit whirl velocity is equal to the rotor tip speed may be deduced. Also, it is possible to evaluate the enthalpy ‘loss’ in the rotor, that is, the difference between the specific enthalpy drop actually occurring in the rotor and its isentropic value.

An attempt is then made to relate this loss with the relative velocities within the rotor passages as predicted by inviscid, two-dimensional analytical techniques. The method developed by Stanitz and co-workers has been programmed to analyse the rotor internal fluid flow properties in the blade-to-blade plane for the conditions of zero incidence. The region investigated does not include the whole rotor, but extends from a boundary upstream of the blade tip to a downstream boundary at a radius equal to 72 per cent of the tip radius. The analysis is performed for overall turbine static to static pressure ratios of 1·2 to 1·6.

The result of the theoretical analysis is to show that the variable ratio of rotor outlet to inlet specific volume with changing pressure ratio is accommodated almost entirely without any change in the flow distribution; that is, over the region of the impeller investigated, and at overall turbine pressure ratios up to 1·6, the compressible flow through the rotor may be considered as being through stream tubes of fixed geometry. There is thus a sound basis for the correlation of rotor loss coefficient in terms of parameters which describe compressible flow with friction along variable area pipes. Consideration is given to the manner in which the zero incidence loss coefficient may be defined in order to remain constant at varying pressure ratios.
Paper 26: The Concurrent Measurement of Momentum and Stagnation Enthalpy in a High-Quality Wet Steam Flow
Authors: Ryley D. J. , Kirkman G. A.
Published: June 2010

This paper describes the problems encountered in the design, operation, and calibration of a small momentum balance fitted within an isokinetic sampling probe located in the test section of a wet steam ‘wind’ tunnel. The probe is suitable for use in air, dry steam, or wet steam. It has an opening of ½ in diameter, a maximum diameter of 1¼ in, and a length of 4½ in, and will detect momentum forces greater than 0·001 lbf. The signal is transmitted by causing the impulse cage to compress a bellows. Turpentine enclosed therein raises the level of its meniscus in a capillary tube and the change in level is observed with a micrometer microscope. An electrical superheating calorimeter is employed in series with the impulse-measuring probe to determine the stagnation enthalpy of the sample. Results are reported for air and steam. For steam the ranges of the respective variables are: pressure, 20–25 inHg vacuum; velocity, 200–500 ft/s; and wetness, 0–10 per cent by weight. Owing to the small size of the momentum cage it was not possible to isolate the contribution to the total momentum made by the entrained liquid.
Paper 31: An Experiment on Erosion Control, Using a 60-Mw Steam Turbine
Authors: Todd K. W. , Gregory B.
Published: June 2010

A twin-exhaust steam turbine of 60-MW output was used for a field study of a method of wet steam erosion control which had been examined previously under laboratory conditions. The last stage of one exhaust was modified so that measured quantities of steam and water could be extracted, or steam injected through slots in the trailing edges of the diaphragm blades.

Variations in erosion rates of the last-stage moving blades in both exhausts were compared by recording continuously the changes in emissivity of radio-active labels attached to sample blades. An introscope was used to study flow conditions during the experiment, and after some five months' operation the set was opened up for inspection, which confirmed the estimates that water extraction reduced erosion by a factor of 5.
Paper 34: A Study of Laminar Convection for Flow down Vertical Annuli
Authors: Sherwin K. , Wallis J. D.
Published: June 2010

Laminar convection in vertical systems is affected by buoyancy so that it becomes a combination of natural and forced convection. In downflow the buoyancy forces oppose the main flow. The problem has previously been studied for flows in vertical circular tubes and is here extended to flows in vertical annuli with uniformly heated inner surfaces. This configuration retains the simplicity desirable for both analysis and experiment, but also represents quite closely certain practical systems such as flow in nuclear reactors in which cylindrical components are placed axially in vertical coolant channels.

Buoyancy forces opposing the main flow cause the fluid to be slowed down near the heat transfer surface until it is eventually reversed. In simple theory this flow reversal is associated with a decrease in heat transfer performance.

An experimental study has been performed in a vertical annulus of ¾ in inner and 2¼ in outer diameter using water. Flow visualization by dye injection indicates that while small reversed flows may occur in a stable form, higher buoyancy forces give rise to radial components of the flow. These radial components cause the reversed flow regime to become unsteady and the Nusselt numbers to be higher than those predicted by laminar convection analysis.