This thesis describes the design, construction and operation of a small pilot plant scale reforming unit using industrial reforming catalysts. Two reactors were used; a tubular packed bed reactor and a spinning basket gas/solid reactor. The range of process conditions in the packed bed reactor was; temperature 300-550 °C, pressure 16-36 bar abs., overall space velocity 0.1-3 vol. liq./hr./vol.cat., hydrogen/hydrocarbon ratio 3-12. The feed hydrocarbon was a C5-naphtha dosed with methylcyclopentane. Axial concentration and temperature profiles were measured in the catalyst bed. In general, the concentration profiles showed rapid initial conversion of methylcyclopentane to benzene and the C6-paraffins. In many cases these profiles reached maxima in the bed before declining as cracking to light products became significant. Data uninfluenced by diffusional limitations was used to compare power function and Hougen-Watson type reaction models. For the methylcyclopentane/benzene reaction the following Hougen-Watson type model is proposed, based on desorption of cyclohexene from the acidic catalyst function as the rate controlling step. The spinning basket reactor experiments (using a methylcyclopentane/hydrogen feed) were carried out in the operating ranges; temperature 300-470 °C, pressure 18-37 bar abs., space velocity 0.1-1.2 vol. liq./hr./vol.cat., hydrogen/hydrocarbon ratio 115-270. Catalyst studies included a bimetallic platinum/rhenium reforming catalyst which was shown to be more active at lower temperature and more selective with respect to benzene production. Kinetic models were studied based on the assumption that the spinning basket could be treated as a continuous stirred tank reactor. This modelling technique was unsuccessful due to lack of stability during mathematical analysis.

Five power transmission systems for heavy vehicles have been studied in this work. These are a multispeed gearbox, a hydrostatic transmission and three split power transmissions. The three split power transmissions are hydromechanical transmissions and each consists of a hydrostatic transmission and an epicyclic gearbox drive. One of them the dual mode system was investigated as a main vehicle drive and also as a steering transmission for tracked vehicles. Four transmission systems were simulated on a digital computer and were also incorporated in a larger simulation which included a typical engine, the vehicle and the torque-speed characteristics of several specified test routes. It was possible to compare the fuel consumptions of these four transmissions, for various specified times to complete the test routes by utilizing a transmission ratio change strategy that selects the lowest engine running speed, It was found that on this basis, the multispeed gearbox had better fuel consumption than the split power transmissions, especially at high engine power levels when the specified times to complete the test route were low. If the different control strategy of maximising the overall efficiency by varying the transmission ratio is adopted, it results in each case, in superior fuel consumption. There was a 9% improvement with the % multispeed gearbox, while the improvements with the split power transmissions ranged from 21% to 29%, The difference in economy for the four systems studied depended on the duty, for instance, very little difference would be discerned between the four systems on the long distance route, However, on a typical U.S.A. urban route, wide range hyrostatic split power systems would show lower efficiencies than both gearboxes and narrow range transmissions, if similar control strategies were possible for these latter systems. In order to investigate the feasibility of this type of optimising control system, for continuously variable transmissions, a system was developed for a vehicle with a simple hydrostatic drive. Air consumption was used as an indirect measure of engine power and the control system scheduled engine speed so that the fuel consumption was minimised. This control system was designed, analysed and installed in a vehicle and comprehensive tests were carried out which show that such control systems are realisable and that the optimizing procedure does not, in any way, impair the controllability of the vehicle. The performance characteristics of a steering system for tracked vehicles, operating as a simple hydrostatic transmission at low track speed differentials and as a shunt transmission at high speed differentials has also been investigated. In the original design, sadden changes of track speed occurred when the mode was changed and it was shown that these changes could be minimised by changing the gear ratio in the mechanical path and also destroking one of the hydrostatic units. Increased vehicle inertia resulted in an increase in the sudden changes of track speed when the mode was changed.

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This work deals with the problem of container loading. It analyses the effectiveness of a layering approach to the problem. The approach is applied to three key areas within this field, the first being concerned solely with the production of efficient, yet stable, loading arrangements for a single container. Using this as a foundation, subsequent work considers the handling of certain practical aspects. The third area of research concerns extensions to the approach in order to tackle situations where all of the cargo needs to be stowed in a set of (several) containers. The work demonstrates that the proposed approach produces packing arrangements which are highly efficient in terms of volume utilisation, and are generally superior to results obtained from a variety of other approaches. Several modified versions of the approach are presented, but it is shown that the original algorithm (with some enhancements of secondary importance) provides a better basis for further work. Where separation of the cargo is required, e.g. when it consists of consignments for different destinations, the layering approach has some limitations. A method of column building, which overcomes these shortcomings, is presented and is shown to be complementaty to the layering approach in terms of the packing efficiency obtained. However, this method has severe drawbacks in relation to load stability. It is shown that practical criteria such as load-bearing ability of boxes and preferences relating to direct contact placements can be incorporated into the layering approach. The method developed uses opportunity cost concepts to govern the placement of boxes. It is demonstrated that the method can produce a significantly higher packing efficiency than is achieved when weight considerations are treated solely as constraints. A system of 'finetuning' is presented that allows the criteria involved to be given user-defined weighting factors. This is shown to be significantly enhanced by a mechanism which checks whether weight aspects are relevant in the current step of the algorithm. This research also demonstrates that the problem of loading multiple containers can often be optimally solved by using one of a number of techniques based on the single container layering approach. Sequential methods, in which containers are loaded one after another by the application of a single container algorithm, are examined. These are compared with procedures where simultaneous consideration is given to the loading of several containers. A computationally more complex method, based on a set covering philosophy, is also investigated as a possible approach. 'This process involves the generation of a number of single container loading configurations and subsequent selection, by integer programming, of a minimal subset which covers the total consignment. The potential of this type of approach is clearly demonstrated

The work presented in this thesis is related to the condition monitoring of rail-wheel interaction using Acoustic Emission (AE), the principle being that both normal and abnormal rolling give rise to AE, features of which are related to the mechanical intensity of the interaction and hence the stress range (or stress intensity factor range) to which sections of track is being exposed. Most of the work was carried out on a model wheel running on a model circular track, which was first characterised using a simulated source before studying the wave propagation from a continuously moving (wheel) source. Using a number of sensor arrays placed on the track, primary wave propagation characteristics such as wave speeds and attenuation coefficients and also secondary wave propagation characteristics such as reflection and transmission from and through the joint. A high speed camera was used to confirm, that wheel slip does not occur at the wheel speeds and loads of interest. A simple analytical model was derived using the measured wave propagation characteristics which describes the expected AE recorded at a track-mounted sensor as the wheel approaches and recedes. Using the analytical model, the effect of increasing wheel speed and axle load on the normal rolling signal was measured. Wheel rattling was observed, particularly at lower wheel speeds and loads, and this was eliminated in some trails by introducing a spacer. The effect of minor track defects and wheel flange rubbing on the track was also studied, where the comparison of the expected normal running signal with excursions above background allowed the locations of track defects to be identified. Finally, a set of experiments were carried out with simulated wheel defects. The signals were analysed using the principle of demodulated frequency resonance and matching to the expected pulse train spectra. . The findings of the work, along with a limited set of field tests on actual train-track interactions allows recommendations to be made for the deployment of sensors for cumulative damage monitoring on critical areas of track.

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