Ethanol is one of a group of hydrocarbon fuels produced from bio-mass which is attracting interest as an alternative fuel for spark ignition engines. Major producers of ethanol include Brazil, from sugar cane, and the USA, from com. Reasons for the growing interest in ethanol include economic development, security of fuel supply and the reduction of net emissions of carbon dioxide relative to levels associated with the use of fossil fuels. Unlike gasoline, which is a mixture of hydrocarbon compounds suited to meet a range of start and operating requirements, ethanol is a single component fuel with characteristics which make engine cold starting difficult, for example. Hence, ethanol is generally used in a blend with gasoline, accounting for <5% in EU pump-grade gasoline to 85% by volume for so called flex-fuel vehicles. Although ethanol is already available in the marketplace, there are aspects of its effects on engine behaviour that are unresolved, including its effects on engine thermal behaviour and heat transfer. These have been investigated in the experimental study presented in this thesis. The aims of this work included determining the effect of ethanol content in blends on combustion characteristics, energy balance, gas-side heat transfer rate and cylinder instantaneous heat transfer. This study covers a range of loads, speeds, spark timings, equivalence ratios and EGR levels representative of every day vehicle use, and has been restricted to fully warm operating conditions. The investigations have been carried out on a modern design of direct injection, spark ignition engine. The performance of different ethanol-gasoline blends has been compared at conditions of matched brake power output. The emissions data for NO, HC, CO and C02, which was used to calculate combustion efficiency, show a decrease in their levels proportional to the increase in ethanol content in the fuel blend. This is owing to an increase in combustion efficiency and change in chemical structure and physiochemical properties. Compared to gasoline, running on 85% ethanol produces slightly faster rates of burning in rapid burn stages of combustion. Typically, the reductions in rapid burn angle are 4%. Results show that the effects do not vary in proportion to the ethanol content in the fuel blend. This is attributable to the fact that, at low and medium ethanol content, the enhancement in combustion gained by oxygen availability is offset by its higher enthalpy of vaporisation and lower heat content. Energy balance data show an improvement in thermal efficiency proportional to the increase in ethanol ratio. This is due to improvement in combustion efficiency and a reduction in coolant and exhaust losses. Results for gas-side heat rejection show that a correlation developed for engines run on gasoline can be used without any modification. The heat rejection rate has been inferred from measurements of heat rejection to coolant adjusted to allow for the contribution of engine rubbing friction. The apparent insensitivity to ethanol content is attributed to a combination of factors. These include the increase in fuel flow rate for a given energy supply being offset in its effect on charge flowrate by a reduction in stoichiometric air/fuel ratio. Gas-side heat transfer results from both the exhaust port and the cylinder show a clear decrease when running on 85% ethanol compare to gasoline. This reduction was also observed in the total measured heat loss to coolant. The magnitude and phasing of instantaneous heat loss is not sensitive to the use of ethanol during combustion. However, as the combustion starts to terminate, lower heat loss for medium and high ethanol content was observed due to the reduction in the combustion product temperature. The results from the C 1 C2 correlation and instantaneous heat transfer are comparable.

Family Mould Cavity Runner Layout Design (FMCRLD) is the most demanding and critical task in the early Conceptual Mould Layout Design (CMLD) phase. Traditional experience-dependent manual FCMRLD workflow results in long design lead time, non-optimum designs and costs of errors. However, no previous research, existing commercial software packages or patented technologies can support FMCRLD automation and optimisation. The nature of FMCRLD is non-repetitive and generative. The complexity of FMCRLD optimisation involves solving a complex two-level combinatorial layout design optimisation problem. This research first developed the Intelligent Conceptual Mould Layout Design System (ICMLDS) prototype based on the innovative nature-inspired evolutionary FCMRLD approach for FMCRLD automation and optimisation using Genetic Algorithm (GA) and Shape Grammar (SG). The ICMLDS prototype has been proven to be a powerful intelligent design tool as well as an interactive design-training tool that can encourage and accelerate mould designers’ design alternative exploration, exploitation and optimisation for better design in less time. This previously unavailable capability enables the supporting company not only to innovate the existing traditional mould making business but also to explore new business opportunities in the high-value low-volume market (such as telecommunication, consumer electronic and medical devices) of high precision injection moulding parts. On the other hand, the innovation of this research also provides a deeper insight into the art of evolutionary design and expands research opportunities in the evolutionary design approach into a wide variety of new application areas including hot runner layout design, ejector layout design, cooling layout design and architectural space layout design.

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It is highly desirable to devise a systematic approach to predict cell – material interactions, especially for novel biomaterial surfaces, and to further understanding in the complex area of attachment and spreading. The aim of this research was to produce a new method of studying morphology in real time, whereby data from live spreading cells can be collected for mathematical modelling. There is an abundance of models for sub-cellular elements, however, there are few calibrated models of whole cells; in particular, three-dimensional models predicting attachment, spreading and cell morphology have yet to be produced. Live HOS cells were imaged using LavaCell membrane stain and CLSM every 5 min for a period of 75 min in this study, capturing sufficient detail to produce three dimensional representations of cells during initial attachment and spreading. In order for the contact line to be measured, the interface between the cell membrane and the substrate had to be imaged in sufficient resolution for accurate measurements of the angles to be made. An image processing algorithm developed using Matlab was able to detect the edge of cells in the CLSM z-stack optical sections. These were then used to create contour plots onto which a surface representing the cell membrane could be added. These reconstructions of cells can be easily manipulated to enable the dynamic contact line of attaching cells to be measured for a model based on two-phase poroviscous flow equations. The three dimensional representations not only showed the changing morphology of spreading cells, but gave data on contact radius and area, contact angle and cell height. The main modelling prediction is a near contact line law, which is given by; Θ3 - Φ3 = 3 µ(n)ln(R/λ) (3nV - J(V,n,... )) γ where Θ is the dynamic contact angle (which remains to be determined by experimental means as the cell is spreading), Φ is the static contact angle, n the network density at the contact-line, J is the mass transfer rate from G- to F-actin at contact line and V equals the outward normal velocity of contact line. Once the method had been developed for glass surfaces, the influence on attachment and spreading of various material substrate and protein conditioning layers was investigated. This was achieved by using transparent thin film coated surfaces of titanium nitride and titanium oxide and pre-coating glass with fibronectin and albumin respectively. Three dimensional representations showed the ability to reproduce the different cell response to each surface and gave comparable morphologies to cells fixed for SEM and immunocytochemical staining.

The thesis describes "Plant Layout System" or PLS, an Expert System which automates all aspects of conceptual layout of chemical process plant, from sizing equipment using process data to deriving the equipment items' elevation and plan positions. PLS has been applied to a test process of typical size and complexity and which encompasses a wide range of layout issues and problems. The thesis presents the results of the tests to show that PLS generates layouts that are entirely satisfactory and conventional from an engineering viewpoint. The major advance made during this work is the approach to layout by Expert System of any kind of process plant. The thesis describes the approach in full, together with the engineering principles which it acknowledges. Plant layout problems are computationally complex. PLS decomposes layout into a sequence of formalised steps and uses a powerful and sophisticated technique to reduce plant complexity. PLS uses constraint propagation for spatial synthesis and includes propagation algorithms developed specifically for this domain. PLS includes a novel qualitative technique to select constraints to be relaxed. A conventional frame based representation was found to be appropriate, but with procedural knowledge recorded in complex forward chaining rules with novel features. Numerous examples of the layout engineer's knowledge are included to elucidate the epistemology of the domain.

The use of coal in the production of energy, will continue around the world into the next century, and onwards. From an environmental perspective, as well as a financial one, man has attempted to increase the efficiency of energy production from initial raw materials. Environmentally, the poor conversion of coal to energy means a waste of earth's resources, as well as the production of more waste. From a financial viewpoint, poor combustion means less energy per tonne of coal, hence less profit. Poor combustion will also mean higher levels of carbon in ash. Increased carbon levels will change the physical properties of the ash, and therefore reduce the possible number of outlets for its disposal. It is essential, from a coal buyer’s point of view that he makes an 'informed' choice, as to the type of coal he is buying, especially if coals in question are imported. There is sufficient evidence to suggest that most techniques that currently exist are unable to characterise world coals successfully. The reason for this has been linked to the unusual petrographic nature of various world coals. It seems logical therefore, that an analytical technique based on the petrography of a coal, would be capable of providing a better characteristic assessment of any given coal type. The use of image analysis in providing petrographic information has been investigated, along with several different techniques for the characterisation of char and coal particles. Char production itself has been studied, mainly concerned with the production of representative char samples. A range of different operating conditions were used, including temperature ranges of 1000°C to 1400°C, oxygen contents of 0 to 3 %, and residence times of 100 to 200 milliseconds. From the experiments carried out, it was possible to correlate char structure to the initial coal using a reflectance/fluorescence program, specially designed for the measurement of a coals 'reactivity'. Other prediction systems, such Rank, Fuel Ratio and Reactive Macerals did not correlate as well to the combustion products from the Drop Tube Furnace.

The work presented in this thesis is aimed at evaluating the potential for using supercritical carbonation (SCC) in conjunction with novel processing techniques, to fabricate new blended calcareous matrix composites with superior engineering properties and lower environmental impacts than conventional cement-based materials. Taking combinations of waste materials such as steel slag (SS) and fuel ash (PFA), binders such as hydrated and cement and various aggregate types to manufacture green forms and exposing them to supercritical carbon dioxide has produced a number of promising ceramic materials. The project looked at novel ways to process the ‘green forms’ from these composites, such as dry- and wet-compression moulding, 3-D printing and hand lay up technique that was adapted from the fibre-reinforced polymer industry. Work concentrated on optimising mix designs, green processing and SCC conditions to produce the highest strength materials. Three main avenues were explored. The effects of mix design, different curing regimes and SCC treatment, on the microstructure and chemistry of the composites was investigated using SEM, TSP, DTA, XRD, helium pycnometry and other techniques. Investigation showed that SCC process significantly enhances the mechanical and microstructural properties of carbonated products. It was shown that SCC treatment activates materials such as steel slag, that in the unground state are not activated by high temperature curing, to form useful composites. It was revealed that the relationship between the ‘degree of carbonation’ and strength is not straightforward and the order in which the various phases in the concrete react is important. Microstructural investigations hinted that the bond between carbonate limestone aggregate and the carbonated matrix was much stronger and more intimate (less porous) than for other aggregates. Chemical analysis also determined how much carbon dioxide could be ‘locked-up’ in the samples and this data was then used in the life-cycle assessment (LCA) of potential products. LCA was used to assess the green credentials of the SCC process and results were encouraging; a net reduction in CO2 emission of around 50% can potentially be achieved. Overall, the project has made many significant advances both in the practical application of SCC to ceramic composite manufacture and in the science of the reaction between sc-CO2 and cementitious phases. The technology could now be exploited by the manufacturing industry as a lowtemperature, rapid, low raw material cost and a sustainable route for manufacture of a wide range of ceramics.

Computer simulation has long been recognised as a useful tool in improved process operation and design studies. Commercial simulation packages now available for batch distillation studies typically assume constant tray efficiency. Here, on the basis of both practical work and computer simulation, the effects of tray efficiency variation with tray liquid composition on model accuracy and column performance are investigated. Detailed modelling studies were carried out on a pilot batch distillation unit and tray efficiency was found to be an important factor affecting the model fidelity. Distillation of different methanol/water mixtures revealed that tray efficiency varies with the mixture composition on the tray, the form of the variation being for the efficiency to pass through a minimum at intermediate compositions. This variation of tray efficiency with tray composition is a known phenomenon, which has not been included in batch distillation simulations even though tray compositions change significantly during a batch run. The model developed in this work (Variable Efficiency Model) includes the tray efficiency variation with mixture composition and results in an evident improvement in model accuracy for methanol/water distillation. The potential effects of strong tray efficiency dependence on mixture composition, at a more general level, are investigated using two case studies, based on hypothetical extensions of the tray efficiency concentration dependence observed for methanol/water mixtures. In extreme cases, the efficiency-composition dependence could introduce a significant additional non-linearity to the process behaviour, resulting in unexpected composition and temperature movements. To quantify the potential significance of these effects, the economic performance of a column based on simulation using the Variable Efficiency Model was compared with its performance, using an overall column efficiency (which is the common practice). Using fixed column efficiency was found to under-predict column performance for low purity products and over-predict performance for high purity products.