Search

Continuous flow chemistry is currently a vibrant area of research, offering many advantages over traditional batch chemistry. These include: enhanced heat and mass transfer, access to a wider range of reaction conditions, safer use of hazardous reagents, telescoping of multi-step reactions and readily accessible photochemistry. As such, there has been an increase in the adoption of continuous flow processes towards the synthesis of active pharmaceutical ingredients (APIs) in recent years. Advances in the automation of laboratory equipment has transformed the way in which routine experimentation is performed, with the digitisation of research and development (R&D) greatly reducing waste in terms of human and material resources. Self-optimising systems combine algorithms, automated control and process analytics for the feedback optimisation of continuous flow reactions. This provides efficient exploration of multi-dimensional experimental space, and accelerates the identification of optimum conditions. Therefore, this technology directly aligns with the drive towards more sustainable process development in the pharmaceutical industry. Yet the uptake of these systems by industrial R&D departments remains relatively low, suggesting that the capabilities of the current technology are still limited. The work in this thesis aims to improve existing self-optimisation technologies, to further bridge the gap between academic and industrial research. This includes introducing multi-objective optimisation algorithms and applying them towards the synthesis of APIs, developing a new multiphasic CSTR cascade reactor with photochemical capabilities and including downstream work-up operations in the optimisation of multi-step processes.

Aims: The aim of the study was to explore and examine the processes and experiences of goal setting at an inpatient rehabilitation unit by video recording and rating goal setting sessions. Another aim of the study was to explore staff, patient and carer perspectives in encouraging patient centred goal setting behaviour by using a newly introduced tool for the purpose of facilitating these behaviours. Methods: Data was collected using three different methods. Goal setting sessions were video recorded and the interactions were coded using a checklist of behaviours. The checklist was compiled from structured observation tools in patient centred care. Simple rating scales were used to record the experience of the sessions. Results from the rating scales were reported using simple descriptive statistics. Focus groups were used to explore staff, patient and carer perspectives in use of a tool that enabled patient centred behaviour. Data from the focus groups was analysed using thematic analysis. Results: The behaviour checklist coded four categories of behaviour – goal setting, goal setting related patient-centredness, generic patient centred behaviours and documentation. A fifth category of behaviours observed from the recorded sessions were also noted. Patients, carers and staff also reported experiencing the sessions as satisfactory with sufficient support and involvement in treatment planning. Focus group results identified three main themes of benefits, barriers and suggestions for using the tool. Conclusions: Exploratory research into the processes involved in setting collaborative goals is crucial in identifying factors that contribute to successful outcomes. The checklist of behaviours could be further developed and used to train and monitor staff. The goal setting tool may be useful as a teaching aid to develop and encourage these behaviours.

Mineral scale deposition/adhesion is one of the major challenges in the oil and gas industry. Besides, the new regulations in the oil and gas industry suggest substituting conventional inhibitors by more environmentally-friendly strategies which may include anti-scaling surfaces as a potential methodology. The objective of this work was to study a new potential application for surface modification near the wellbore to reduce mineral scale deposition in the rock. To achieve this purpose, it was required to form a thin layer of a chemical, which has a strong bond with quartz and does not block the oil path; and has a potential to reduce the scale deposition/adhesion on the rock. 3-aminopropyl-triethoxysilane (APTES) and p-aminophenyltrimethoxysilane (APhS) with various concentrations were chosen to create self assembled monolayer to alter the physical and chemical properties of the surface. The kinetics of the APTES (2-8%) film formation on the surface was studied by QCM. Langmuir isotherm was used to interpret the QCM results and to calculate the surface coverage of APTES film on the surface. Also the performance of quartz surfaces which were treated by different concentrations of APTES and APhS in terms of reduction of scale deposition was studied in low=4.77 and high=54.8 saturation ratios. The best film performances (up to 95%) were obtained by 0.06% APhS and 6% APTES, respectively. It was assumed that the reduction of scale deposition could be related to the reduction of nucleation sites on the treated surfaces due to changing the surface charge of quartz surface from negative to neutral (slightly positive) surface. Surface composition, wettability and the roughness of APTES and APhS films were characterised by XPS, Contact angle Goniometry and surface profiler, respectively. Based on the film characterisation results, the most effective parameters in reduction of scale deposition were the surface composition and film conformation.

Understanding the cement injection behaviour in cancellous bone and accurately predicting the cement placement within the vertebral body is extremely challenging. We propose a novel method using reproducible and pathologically representative 2D and 3D bone surrogates to help study the influence of cement properties on injection behaviour. Bespoke methodology was developed to control the injection volume and flow rate, measure the injection pressure, and allow visualization and quantitative analysis of the spreading distribution. Morphology analysis showed that the variability in the 2D and 3D bone surrogates was very low, indicating that the geometrical structure of the surrogates was constant. The overall pore size of the surrogates was very similar to that reported for human osteoporotic vertebral cancellous bone, indicating that the surrogates were pathologically representative. Injections performed into the 3D surrogates revealed that an increase in the fluid starting viscosity significantly increases the injection pressure in all surrogates, decreases the risk of leakage for osteoporosis surrogates only, decreases the mean spreading distance for multiple myeloma surrogates only and increases the sphericity causing a more uniform spreading pattern for the metastasis surrogates only. Injections performed into the 2D surrogates highlighted the influence of cement formulations and model structure on the injection behaviour and showed that (i) cements with similar composition/particle size have similar flow behaviour, (ii) cements with a high liquid-to-powder ratio cause irregular filling patterns and have a high risk of leakage, and (iii) the injection behaviour of certain cement formulations improves in the presence of lesion or fracture, suggesting the notion of pathology specific bone cements. The developed methodology provides a fast, robust tool for discerning subtle differences in bone cement formulations and allows comprehensive assessment of cement flow behaviour through controlling the surrogate morphology, controlling the injection parameters, measuring the injection pressure, and allowing the visualization and quantitative analysis of the spreading distribution. The advantage of this methodology is that it provides a clinically relevant representation of cement flow patterns and a tool for validating computational simulations.

The aim of this project was to benchmark energy utilisation of bread manufacturing and to provide methodologies and results with the aim of improving efficiency in commercial bakeries. The bread industry is an important provider of staple food products across the world. Owing to the large energy use in bread manufacturing, bakeries have come under increased scrutiny to reduce their environmental impact. The proving process exposes dough to heat and humidity in order to encourage yeast activation. Provers (responsible for 5 % of carbon emissions in bakeries) are over-engineered to the extent that energy costs impact upon performance. The industry standard practices that use large volumes of airflow to maintain food safety have not been scientifically justified. Experimentally validated Computational Fluid Dynamics (CFD) simulations showed the residence time distribution profiles for different numbers of air changes. The results have indicated that it is possible to reduce airflow by 33 % and electricity demand by over 70 %. A system-level thermodynamic analysis was developed in order to measure and model heat streams in industrial bread ovens. The model was subjected to a sensitivity analysis to ensure the calculations could be trusted to give suitably accurate results. A number of measurement techniques were employed and the methodology was designed to increase the potential for industry-wide use to assess the efficiency of ovens. The results showed that between 40 and 49 % of heat is wasted in industrial ovens. The model has been successfully distributed to industry. Experimental measurements of heat transfer for a range of regimes used in baking ovens were undertaken. The results were validated by previous correlations published in literature. Investigation focussed on three particular novel research areas. Firstly, comparisons between nozzle types showed that rows of circular jets could be approximated as slot nozzles for mean heat transfer. Secondly, the ratio of convective to radiative heat transfer was investigated. Thirdly, the prevalence of secondary peaks in local heat flux profiles was compared for two nozzle sets. These unique results can be used to help design baking ovens with energy efficient operating conditions.

A data centre can be defined as an infrastructure facility that houses file servers, processors and other computer equipment, along with a standby power supply. These servers are kept inside cabinets and those cabinets are called racks. These racks are located close to each other inside a data centre to form rows. These rows are located front to front and back to back to form the aisles. These aisles could be used to supply the chilled air and also to provide room for operational purposes. Data centres are now widespread due to the high demand of infrastructure requirements, such as the network to operate Internet services. In this thesis, research is focused on the air cooling method, a popular method of cooling that is used to cool many data centres. The aim of this thesis is to understand the capabilities and limitations of Computational Fluid Dynamics (CFD) analysis of cooling air flow in data centres. The data centre components, which are the server blade and rack, have been simulated in order to study the environmental conditions (temperature, pressure and velocity fields) inside the data centre; as such, CFD analysis has been carried out at server, rack and room levels. The proposed method of a porous media model has been implemented to simulate servers and racks and has been tested and validated through corresponding experiments. It is shown from the results that the porous media model provides good agreement with experimental data of an actual case at the server level. The server racks have been simulated as a porous media with different permeability values in each direction (x ,y, z). In addition, a 3-dimensional CFD model has been used to explore the performance of three different room level cooling strategies based on the aisle containment (cold and hot aisle containments) and back door cooler. It is shown that using either cold or hot aisle containment within a data centre provides significant improvement inside the data centre with respect to temperature distribution and the avoidance of hot spots. Finally, the power input to the computer room air conditioning (CRAC) unit has been analysed for different cooling configurations when assuming the Coefficient of Performance (COP) of either direct expansion CRAC unit or a chiller system. Furthermore, the comparison between active and passive back door coolers has been done to evaluate the power consumption in the CRAC unit. It is shown that the supply temperature inside the data centre has a significant effect on the CRAC power input (compressor work) of the DX CRAC unit. With respect to comparison between the active and passive back door coolers, it has been found that the reduction of the CRAC unit load is higher when using the active back door cooler compared to the passive back door cooler, so the active back door cooler is better than passive back door cooler with respect to reduction of load on CRAC unit.

Material wear due to erosion-corrosion in slurry transport equipment is prevalent in process industries such as the oilsands industry. Damage to equipment can cost a typical oilsands industry nearly £200 million annually, along with an associated health and safety risk to man and environment [6]. New materials are continuously developed in order to endure wear under adverse erosion-corrosion conditions better and laboratory testing offers a good option to test new materials prior to commission. Traditionally the performance of a set of new materials are assessed based on their overall wear behavior in a laboratory test and is ranked accordingly, with the best performing material generally used for application. However, due to differences in prevailing conditions on the material surface and geometrical variations between actual and test geometry, accurately correlating data from a laboratory test to field scenario can be highly complex. Also the ranking system is not capable of predicting wear profiles for specific conditions and hence a new wear prediction method was developed and is presented in this thesis. This method has been developed, using a combination of standard laboratory based experiments and Computational Fluid Dynamic (CFD) simulations. As a starting point only wear due to erosion is considered and this thesis provides validation of such an approach. The method involves two stages in which (i) a universal wear map is generated for the material and abrasive combination in question using a standard laboratory test Uet impingement test) to generate a wear scar on a simple geometry. The local wear rate from this is interpreted using a CFD simulation of the test to generate a map giving local wear as a function of particle impact velocity and angle; (ii) a CFD solution is calculated for a series of different erosion configurations giving the particle impact data at each point on the surface. The wear map from the first stage is then used to give the local wear rate. The power of this method is that once a material-specific map has been generated then wear on any geometry can be calculated through the simulation of flow using CFD. As validation of this, wear on a typical plant geometry (1.50 90 0 elbow bend) is undertaken and the general applicability of this method is demonstrated.