bluuebunny/crossref_metadata_2025_split huggingface dataset:
Paper 9: Combustion Aspects of Industrially Applied Aero Gas Turbines
Authors: Pilkington G. , Carlisle D. R. 
Published: June 2010

This paper concentrates on the combustion experience gained by the application of the Rolls-Royce Avon aero gas turbine to industrial usage and each of the following subjects is considered in detail. A brief summary of the design philosophy which has dictated the configuration of the basic aero combustion equipment. The particular implications of industrial operation as this affects the combustion system. This includes the effect of different fuels and operation for long periods in a ground level environment. The operational problems experienced to date with the basic aero equipment and the design and development work undertaken to overcome them. These problems comprise frettage, flare distortion, smoke output, starting, corrosion and combustion stability. The design and development of an improved system, now under way, which will be capable of satisfactory operation with a wide range of liquid or gaseous fuels without component change. The use of steam injection into the combustion system as a means of improving overall cycle efficiency. Consideration of the range of industrial fuels available, from diluted gases to distillate and residual oils, and their suitability for gas turbine usage. Future trends in combustion technology.
Paper 12: Gas Turbine Fuel and Control Systems
Authors: Warne E. H. 
Published: June 2010

Following a preliminary introduction on the necessity for fuel and control systems, it is proposed to deal in some detail with the requirements of modern gas turbine engines from the point of view of both pumping of fuel and the control. In general the paper deals with aircraft type systems. Over the last 20 years specifications have been increasing in size and the need for the additional requirements will be discussed in relation to the various types of engines. Considerations of control for two- and three-shaft engines for both civil (subsonic and supersonic) and military use are covered, as also are the somewhat different requirements for helicopters. In addition to main engine control, the effects of reheat, supersonic nozzles and variable engine geometry will be discussed. Reference is also made to the increasing severity of environment on high speed aircraft. Following this, the problems of pumping are considered and a review of the types of pumps available is made comparing their relative advantages and disadvantages in relation to the application, and indicating the general trends in this field. On control systems the types of control available will be discussed including hydromechanical, electric and fluidic, and the basis on which the optimum choice can be made for any particular engine will be dealt with. The requirements for control, both for steady running and limiting will be explained, and once again a typical example of a control system is briefly described.
Paper 13: Recent Developments in the Control of Industrial Gas Turbines
Authors: McArthur M. J. , Charles P. W. 
Published: June 2010

This paper describes the control systems required for the application of gas turbines to fully automatic generating stations, and mechanical drives such as natural gas compressor stations. Gas turbine power plant has definite advantages in that for the power output it lends itself to relatively simple fully automatic operation of the overall plant and rapid starting and loading. The relatively low capital cost and size have resulted in widespread applications of this type of plant. The large gas turbine plant can be divided into two main categories: (1) Aero powered gas turbines. (2) Pure industrial gas turbines. The role of the control system is not only to adapt the gas turbine to the particular application but to ensure the safety and protection of the plant at all times. The control functions include: Those necessary for the particular application, e.g. power turbine speed control. Those necessary for the protection and correct operation of the gas turbine system, e.g. balance of multiple gas generators discharging into power turbine. The peripheral systems, e.g. automatic sequence systems for starting. This paper is based on the author's recent experience in this field.
Paper 14: The Advancement of Controls with Modern Gas Turbines
Authors: Abraham G. A. 
Published: June 2010

One of the claims attributed to gas turbines by their pioneers was their simplicity of design. Although this claim can still be applied to some engines, others with variable intake geometry, bleed valves, movable guide vanes, multi-staged turbines and recuperators have stretched the definition of simplicity. The control of these engines to satisfy the varying demands has also become complex and aggravated by the mixing of control media. The paper discusses advancements in control technology and how these advancements can affect both the design and application of gas turbines.
The Hydrodynamic Lubrication of Piston Rings
Authors: Lloyd T. 
Published: June 2010

Although the piston ring is a critical component in a reciprocating engine and although its successful functioning depends upon adequate lubrication, very little work has been done on the analysis of piston ring operation as a phenomenon of hydrodynamic lubrication. This paper outlines briefly the theoretical and experimental work that has been done, and produces a new analysis particularly suited to solution by computer. The analysis assumes: that the shape of the piston ring face is parabolic, but not necessarily symmetrical; that the lubricant viscosity is constant under the ring, but may vary in any fashion over the piston stroke; that oil film disruption may be represented by calculating oil pressure assuming no disruption and then discarding negative pressures; that the pressure upstream and downstream of the ring and the load on the ring may vary cyclically over the stroke; that there is circumferential symmetry; and that the motion of the ring parallel to the cylinder face is that of the piston, while the motion perpendicular to the cylinder face satisfies the force balance. Using the simple example of the symmetrical ring face, isoviscous lubricant, constant load, zero upstream and downstream pressures, and sinusoidal piston motion, it is shown that there exists a parabolic shape which maximizes the minimum oil film thickness. Comprehensive results are presented for this case. The use of the more general analysis is illustrated for a diesel engine design for which the ring face shape has been measured.
Paper 3: Reliability Prediction
Authors: Green A. E. 
Published: June 2010

Reliability has been described as a parameter of design. Where there is a large amount of capital at stake, or a risk to human life, the characteristic of reliability becomes very important. The designer may base his estimates of reliability on: (1) field experience; (2) sample testing; (3) prediction. In high risk situations it is suggested that prediction techniques play an essential part in early design. The need is stressed for the quantification of reliability; this will tend to remove the subjectiveness and thereby help communication. The methods of prediction are considered, based on a suitable reliability definition. These methods range from obtaining a consensus of opinion from a body of people to the mathematical modelling techniques employed by individual designers and assessors. The reliability data available on component parts are surveyed and used as the basis for describing current techniques for predicting the reliability of equipments and systems. In particular, the techniques for the safety analysis of various modes of failure are considered. The correlation between predicted and practical results is described for some applications. Conclusions are drawn on the general applicability of the prediction methods and the requirements for an organized reliability data bank.
Paper 11: The Control of Quality in Power Plant: (A Large User's Campaign against Manufacturing Defects)
Authors: Burgess N. T. , Levene L. H. 
Published: June 2010

As an extensive user and purchaser of engineering products, the C.E.G.B. has a national responsibility for ensuring a continuous improvement in the quality and reliability of power plant. There has always been close collaboration between the C.E.G.B. and its suppliers in research and design; this collaboration has become closer in recent years as technology has rapidly advanced in the power station field. To permit timely and trouble-free commissioning of large boiler/turbo-generator units with satisfactory reliability in service, the C.E.G.B. and its suppliers are now appreciating the need for an equally close relationship throughout the manufacturing and erection stages. To assist in this, a Quality Control Unit was set up at C.E.G.B. Headquarters to encourage plant suppliers to accept the principles of quality control, and so bring about improvements in their organization and product. An account is given of the work of the C.E.G.B., which collaborates with contractors on quality assurance matters and certain manufacturing problems at works and on sites. There is also co-operation on specifications, standards of acceptance and non-destructive testing, and the assessment of sub-contractors. In addition, the Quality Control Unit acts on feedback data from the field, and details are given of some recent operational failures resulting from manufacturing defects, and their cost to the Board.
Paper 13: Creep Deformation and Fatigue Failure of Structural Materials
Authors: Darlaston B. J. L. 
Published: June 2010

In support of the vast amount of stress analysis work on components, considerable effort is required to provide suitable materials behaviour models. Simple laboratory tests on uniaxially loaded specimens under constant temperature condition provide the bulk of data, but methods are required to translate these data to multiaxial conditions with non-uniform cyclic loading and cyclic temperature. The material behaviour laws, therefore, are aimed at meeting two requirements: first, to predict the deformamation response in terms of the imposed loading conditions and the previous history of the material; and second, to analyse the stress or strain cycles to predict failure. This paper reviews the steps being taken at Berkeley Nuclear Laboratories, C.E.G.B., and elsewhere to achieve these two objectives.
Paper 16: The Management of Maintenance and its Impact on Safety and Failure of Components
Authors: Fair D. R. R. , Maxwell E. W. 
Published: June 2010

The various influences exerted by management at different levels of an organization to secure reliable and continuing operation of electricity generating plant are dealt with. Consideration is given to the requirement at the top executive level for the strategic planning and scheduling of plant outages for maintenance and overhaul, to ensure the minimum cost of production from an integrated supply system consistent with obtaining long-term reliable operation of individual plants. Also considered is the requirement for various management levels at those plants to provide detailed planning of work content, resources, and logistics associated with maintenance of individual plant items. The collection and analysis of plant performance data, to determine correct work content and frequency of routine maintenance to provide an economic balance between outages due to maintenance and outages due to failure, are studied together with the constraints imposed by statutory inspections. Diagnostic testing of electrical and mechanical plant to help reduce plant outage time, and the influence of non-destructive testing techniques on reducing expensive cascading failures, are examined. The influence of correct utilization of tools, maintenance equipment, and methods of working on minimizing plant down time and the use of special equipment to facilitate inspection of inaccessible plant in both the conventional and nuclear fields are also considered.
Paper 21: Planning for Failures
Authors: Brook R. H. W. 
Published: June 2010

When a serious failure situation has developed, an expensive crash programme is usually required. If in-service data are analysed as a routine, then impending trouble may be foreseen and management decisions made to minimize the cost. A reliability analysis can help to establish a failure pattern compatible with intuitive engineering assessment so that, from a realistic prediction, alternative courses of action can be considered. A recent gas-turbine engine problem which has caused six component failures is analysed, and alternative replacement strategies are considered. It is suggested that to adopt the intuitive compromise strategy could be the most expensive in this case.
Paper 27: Supplier/Customer Relationship
Authors: Shaw J. F. St G. 
Published: June 2010

The need for definition of the rights and duties of each party to a contract is discussed. The development of standard conditions of contract is traced. The risks undertaken by both parties are considered in relationship to the type of contract agreed upon and the guarantees which may be expected both on technical performance and completion. The types of organization provided by both customer and supplier to carry out their relative responsibilities are reviewed in relation to the efficient and timely completion of the works and to the avoidance or settlement of disputes. The status of the ‘engineer’ is defined, and his function in securing proper observance by both parties of their responsibilities is enlarged upon.
Paper 29: Systematic Design Review and Fault Analysis
Authors: Green J. 
Published: June 2010

Comprehensive failure analysis methods are currently available to electronic designers, extending to the use of computers to estimate the probability of failures. The mechanical designer has few such tools at his disposal. The paper presents two practical methods of reviewing a mechanical design to improve its reliability. The first is a potential fault analysis, which considers each component and its relation to the function of the whole. The use of this analysis as a project control method is also shown. The second method is a systematic design review method, which aims to consider every aspect and function of a design and its components, to ensure that no factor has been overlooked. The application of these methods is discussed.
Paper 30: Cause and Effect of Failure—an Insurer's View
Authors: Brown J. C. 
Published: June 2010

Engineering insurance has its origins in a nineteenth-century co-operative for the inspection of boilers, and plant inspection remains a large part of the business. The companies concerned together employ about 2250 surveyors throughout the country. The paper describes some of the more common types of plant failure met by the insurance companies and discusses their causes and remedies. Failures may cause damage not only to the item concerned but to surrounding plant and property and may affect the ability of an undertaking to remain in profitable business. The availability of insurance cover for most engineering risks is explained.
Hydrodynamic Studies of Two-Phase Upflow in Vertical Pipelines
Authors: Jepsen J. C. , Ralph J. L. 
Published: June 2010

The object of this study was to obtain data on the radial variation of gas- and liquid-phase mass flux profiles in two-phase upflow in vertical pipelines. Experimental data were obtained on the radial gas-liquid flux, impact pressure, and linear liquid-phase velocity profiles for superficial gas- and liquid-phase velocities ranging from 20 to 125 ft/s and from 5 to 15 ft/s, respectively. Studies were made on 1-in, 4-in, and 8·4-in vertical pipelines and in a 1-in i.d. by 8·4-in o.d. vertical annular flow pipeline. Gas-liquid systems studied were air-water, air-aqueous glycerol, and air-tetrabromoethane. In Part 2 time-averaged radial liquid hold-up and linear-phase velocities were estimated from radial mass flux and impact pressure data. Estimates were also made on the magnitude, frequency, and velocity of the flow disturbances. Empirical correlations for mean liquid hold-up and pressure drop were developed from experimental data.
A Study of the Performance of Inertia Air Filters
Authors: Gee D. E. , Cole B. N. 
Published: June 2010

This paper presents an experimental and theoretical study of the design and performance of inertia air filters, with particular reference to rail traction duty. Using a specially constructed test rig, performance testing of commercially available filters was carried out over a wide range of operating conditions. Subsequently, a more fundamental study of some design variables was carried out in a small-scale test rig. The testing was supported by a theoretical approach using a digital computer model of the inertia filtration process. The results of the work indicate that the inertia filter is suited to high-volume, low pressure drop applications. However, operational difficulties, owing to dust build-up occurring within the filter and variations of bleed ratio, may be encountered. The theoretical model was shown to reproduce all the major operating characteristics of the filters measured in the test programme, and to respond to design changes in a similar way to that indicated by earlier published work. A hypothesis of the mechanism of separation is proposed, and it is suggested that the performance of new filter layouts can be examined at the design stage. Supporting work describes the selection, measurement, and production of a suitable range of polydisperse solids for the test programme.
Two-Phase Air-Water Flow in a Slot-Type Distributor
Authors: Madden J. M. , St. Pierre C. C. 
Published: June 2010

Experimental data have been obtained for two-phase air-water flow through a slot-type distributor. Air and water flow rates through the slot were measured as the pressure drop across the slot was varied for fixed values of the main stream quality, the total mass flux, the slot length, and the slot width. Five different slots were cut in the side of a vertical 1-in internal diameter plexiglass tube and a controlled pressure drop across the slot was used to remove a portion of the main stream. Three slot lengths were used: 1·66 in, 4 in, and 6 in. The mass flux was varied from 200 000 to 500 000 lb/h ft2 and the air quality ranged from 0·2 to 0·7 at a system pressure of 50 lb/in2 (abs.). The orifice equation employing discharge coefficients was successful for calculating cross-flow rates. Two-phase flow discharge coefficients are correlated as a function of the ratio of slot velocity to mainstream velocity. At low cross-flow velocities or large mainstream velocities the hydraulic resistance to cross-flow increased by as much as an order of magnitude. The axial pressure rise across the slot was also measured for both single-phase air and two-phase air-water flows. Values of the momentum correction factor, which accounts for the diverging stream not leaving at right angles to the main flow channel, were determined.
Some Experiments on Sonic Velocity in Two-Phase One-Component Mixtures and Some Thoughts on the Nature of Two-Phase Critical Flow
Authors: Barclay F. J. , Ledwidge T. J. , Cornfield G. C. 
Published: June 2010

The pressure drop characteristics and flow rates encountered in measurements of flashing water flow in parallel-sided pipes cannot be simply related to the thermodynamic equilibrium theory of the velocity of sound in homogeneous two-phase one-component mixtures. It is shown in the paper that the velocity of propagation through such a mixture is different in magnitude, both to the thermodynamic equilibrium theory and to the theory postulating no phase change. Measurements of the velocity of propagation of compression and rarefaction waves in atmospheric pressure stagnant boiling water are described and interpreted. Some aspects of bubble motion in a pressure gradient are discussed. Measurements in stagnant water are not precisely relevant to the case of flowing liquid in which the vapour component is slipping positively with respect to the liquid. The effect of slip is discussed. It seems to the authors that some relationship between the sonic velocity obtained from their tests and the critical velocity correctly defined in terms of local pressure slip and void fraction should exist. The data which should be extracted from a critical flow experiment are suggested.
Effect of Rapid Steam Off-Take on Natural Circulation in Boilers
Authors: Simpson H. C. , Rooney D. H. , Callander T. M. S. 
Published: June 2010

This paper describes investigations into the effect of a sudden change in system pressure, caused by rapid steam off-take, on a natural circulation loop. The work was carried out on a two-tube experimental boiler with a water drum connecting the bottom of the riser and downcomer tubes, which were respectively 2 in o.d. x 9 s.w.g. and 11/4 in o.d. x 6 s.w.g., giving a riser to downcomer flow area ratio of 3·9. The experimental range covered starting pressures of 1000, 800, 650, and 500 lbf/in2 (gauge), with pressure drops of 100 lbf/in2 at rates ranging from 1 to 34·5 lbf/in2 s. Heat fluxes to the riser tube ranged from 21 000 to 136 000 Btu/h ft2 and initial mass velocities from 0·70 to 1·11 million lb/h ft2 in the downcomer tube. During the transients, continuous recordings were taken of system pressure, circulation, pressure difference, and fluid density at a point in both the riser and the downcomer tube, using the gamma-ray attenuation method. The system behaviour was analysed theoretically by setting up the appropriate two-phase conservation equations and solving them using (1) a finite difference method, (2) a stepwise solution on the basis of quasi-steady flow. The first method was eventually discarded in favour of the second. The theoretical flow models considered in the analysis include a vapour core annular type flow in the riser, and a homogeneous type flow in the downcomer, during the transient. The theoretical results are compared with the experimental data.
Heat Transfer Rig for Hydrogen-Cooled Generator Field Windings
Authors: Davidson D. F. 
Published: June 2010

The maximum output from large turbine generators is limited mainly by the temperature rise of the rotating field winding. Hydrogen at a pressure of several atmospheres is normally used to cool this winding by direct contact with the copper. Accurate knowledge of surface heat transfer coefficients is essential to ensure that the average winding temperature rise does not exceed the specified value. A heat transfer rig was built to test full-size rotor coils in hydrogen and to compare actual with predicted copper temperatures. The construction of the rig is described, together with details of its operation and the various problems which had to be overcome. Tests were carried out on two designs of rotor coil. In one case the flow is laminar, and in the other it is turbulent. The test results are compared and the various heat transfer coefficients evaluated.
Some Designs for Mountings Incorporating Two Rolling Bearings and a Grease Relief System
Authors: Mullett G. W. 
Published: June 2010

The designs for grease relief systems of the valve type for a mounting containing a single bearing are already well known. In some machinery, however, the bearing requirements cannot be satisfactorily met by a single bearing. In these cases a pair of bearings in the one mounting is needed. The design of the mounting is further complicated if, in addition to pairing the bearings, a grease relief system is also required. The paper gives eight outline sketches covering various designs of two-bearing grease valve mountings. All have been rig tested and the efficiency of each design categorized. For the experimental work 3-in (76·2-mm) bore medium series ball and roller bearings were used. These were grouped into six pairs. Each pair was tested, either paired in contact or axially spaced apart. Shaft speeds ranged from 1070 to 3600 rev/min, DN = 82 000 to 275 000. In the relief systems, either one or two valve discs were variously positioned above, below, and between the bearings. The paper should be of value to design engineers.