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The Power Electronics Research group at Aberdeen University is working towards providing a complete time domain model of an electrical drive for marine applications. Effects such as vibration, shaft and propeller induced oscillations and noise in ships due to the use of cycloconverters will be studied in this way. This thesis therefore reports the investigation of machine vibrations resulting from electromagnetic forces. The machines of primary interest are ac induction machines, but much of the work reported in this thesis has broader significance. To assess the vibration problems of propulsion motors, the exciting force and the vibration behaviour of the motor must be modelled. The investigation has therefore been carried out in five principal areas. The development and use of a new time domain magnetic force model. The development of a method to calculate machine stator natural frequencies. A laboratory investigation of system parameters of both a stator and also an entire motor, which draws important conclusions not previously reported. A machine vibration prediction method based on analysis of interactions between the magnetic forces and the motor system parameters. Vibration measurements on a machine to provide data for correlation with predicted results. The Saber simulator has been used throughout to develop the force calculation model. The force model is used to calculate the time and space dependent magnetic force wave, in particular, when the motor is loaded and fed from a nonsinusoidal converter, which makes this model particularly useful for machine vibration calculations. The computer model can be readily used with previously developed cycloconverter models to achieve a complete cycloconverter propulsion simulation.

Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1977. / Bibliography: leaves 125-126. / Microfiche. / x, 126 leaves

To date, the 50 km/h General Urban Speed Limit (GUSL) has been implemented to some local residential streets in the City of Port Adelaide Enfield (hereafter referred to as Port Adelaide), South Australia as a Local Area Traffic Management (LATM) scheme since March 2003 aiming to reduce travel speeds and traffic volumes so as to enhance road safety and amenity of residential areas. Port Adelaide is located approximately nine kilometres away from the North-west of Adelaide Central Business District (CBD). There are major express highways and freight roads enclosing Port Adelaide, and within the boundaries is composed of many arterial and collector roads. All of these arterial roads and some major collector roads line in north-south direction. As a result of these geographical characteristics, Port Adelaide is a city covering the major direct routes for residents and major freight route for goods transport in the north-west suburbs. / However, one of the problems occurring in Port Adelaide seems to be characteristics of grid road networks lacking clear road hierarchy, which can be seen from many local streets connecting directly with nearby arterial and/or collector roads. Furthermore, as described previously Port Adelaide consists of many freight routes, arterial routes, and these characteristics cause another problem. Traffic is induced to divert to local streets, which are relatively straight, and uses them as an alternative route causing many problems to residents in the local area due to travel demands during rush hour. To this point, it can be seen that the 50 km/h GUSL scheme might not be as efficient as it should be in deterring through traffic since the implementation of traffic management has not covered a macro scale, which in this case is arterial roads forming a connective grid. / This study seeks to present the analysis of traffic data in terms of traffic volumes, mean speed and 85th percentile on three different local residential streets during weekday and soma crash data analysis is also done on two study streets. The expected results of this study may be taken as samples for further research in future. / Thesis (MTransportSysEngineering)--University of South Australia, 2006.

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It is well known that high-speed liquid jetting is one of the most powerful techniques available to cut or penetrate material. Recently, it has been conjectured that high-speed liquid jets may be beneficial in improving combustion in such applications as SCRAM jets and direct injection diesel engines. Although there are practical limitations on maximum jet velocity, a fundamental study of the characteristics of high-speed liquid fuel jets and their auto-ignition feasibility is necessary. Important benefits could be increased combustion efficiency and enhanced emission control from improved atomisation. The generation of high-speed liquid jets (water and diesel fuel) in the supersonic to hypersonic ranges by use of a vertical single stage powder gun is described. The effect of the projectile velocity and projectile mass on the jet velocity is found experimentally. Jet exit velocities from a range of different nozzle inner profiles and nozzle hardness are thoroughly examined. The characteristics and behaviour of the high-speed liquid jet and its leading bow shock wave have been studied with the aid of a shadowgraph technique. This provides a clearer picture of each stage of the generation of hypersonic liquid jets. It makes possible the study of hypersonic diesel fuel jet characteristics and their potential for auto-ignition. The fundamental processes by which a supersonic liquid jet is generated by projectile impact have been investigated. The momentum transfer from the projectile to the liquid and the shock wave reflection within the nozzle cavity are the key items of interest. A new one-dimensional analysis has been used in order to simplify this complex and difficult problem. The impact pressure obtained from the projectile was firstly derived. Then, an investigation of the intermittent pressure increase in a closed end cavity and a simple stepped, cross-sectional nozzle were carried out. The nozzle pressure and final jet velocity were estimated and compared to a previous method and to experimental results. Some interesting characteristics found in the experiments relate well to those anticipated by the analysis. The characteristics of a hypersonic diesel fuel jet and its leading edge shock wave were assessed for their potential for auto-ignition using fuel with cetane numbers from 50-100. The investigations were performed at normal ambient air and at elevated air (110 ???C) temperature. So far, there is no sign of auto-ignition that may occur because of the temperature rise of the induced shock.

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