Metal foams, a new class of porous material with highly permeable structure and higher porosity (>0.60) compared with classical porous granular beds, are a viable solution to enlarge the thermal exchange area and provide a high heat capacity and high specific area. These metal foams are available in a number of solid materials with different porosities and pore size. There is a current lack of understanding regarding metal foam microstructure parameters’ effects on hydraulic and thermal parameters. This is a barrier to the design and implementation of various industrial applications. The current study aims to discover the effects of the pore shape and morphological parameters in terms of pore size and porosity at relatively low ranges of porosity on fluid flow and conductive and convective thermal transport phenomena. The manufacturing defects were tracked using the image processing technique for scanned surfaces samples. The effect of these defects on the thermal and hydraulic parameters was also studied.

Thermal instability in aviation fuels has been thoroughly explored over the last 50 years. The problem is complex, with coupling of fuel chemistry, heat transfer and fluid dynamics. Most efforts have been applied to the chemical kinetics of deposit formation and studying physical effects such as temperature, flow rate and Reynolds number in a multitude of small to large scale testing devices. However, much less attention has been paid to the effects of wall surface roughness. This is surprising - since for turbulent flow, wall roughness enhances momentum, heat and mass transfer by disrupting the quiescent viscous layer adjacent to the wall and interfering with structures of turbulence further into the boundary layer. Furthermore, a rough surface increases the wall surface area, presenting more active sites for heterogeneous catalytic reactions. Additive Layer Manufacturing (ALM) has been touted as ’game changing’ technology and is now being proposed as a method to create components for gas turbine engines. The technology results in near net shape parts with reduced weight, number of welds and material waste compared to conventional subtractive machining methods. However, the surface roughness of ALM components can be orders of magnitude greater than machined components and can be highly non-uniform. While reducing external surface roughness is trivial, typical methods of internal roughness reduction (ie. abrasive flow machining) may not be possible for small scale passages. This may result in internal fuel passageways with high relative roughness in components which are subject to high thermal loading - for example, injector feed arms which are exposed to compressor discharge air. The effect of wall roughness on deposition of thermally stressed aviation fuel was investigated in both laminar and turbulent flow regimes using small to medium scale test devices. Deposition over ALM components was tested in the laminar regime with a modified Jet Fuel Thermal Oxidation Tester (JFTOT) and in the turbulent regime with the Aviation Fuel Thermal Stability Test Unit (AFTSTU). The High Reynolds Number Thermal Stability Tester (HiReTS) was used to examine deposition in micro-scale tubes with very high relative roughness. As well as microscopy and 3D optical profilometry, momentum and heat transfer experiments were conducted to characterise the roughness as fully as possible. In the laminar regime, the effect of roughness was negligible. For turbulent flow, substantial differences in heat transfer and deposition rate were consistently observed for tubes with the highest relative roughness. The increase in deposition rate is thought to be related to the projection of roughness elements into regions of intense turbulent activity in the boundary layer. The turbulence structures, which are more energetic and have reduced anisotropy over rough walls, increase wall-normal transport - thereby replenishing the near wall region with deposit precursor and providing insoluble particles formed off the wall with inertia with which to deposit.

The process of urbanisation has a major influence in determining the microclimate condition in urban areas through physical and social developments. With the estimation of 67 % world population will be living in the urban areas in 2050, modification of urban climate through urban heating will continually occur by adapting artificial urban surfaces to accommodate the demands from urban dwellers. This thesis highlighted the mitigation strategy by applying solar collector system embedded underneath road pavements, RPSC due to the concern of heat release from the ground road surfaces to the nearby air temperature, which indirectly affects the outdoor thermal comfort and elevates the urban heat island (UHI) effect. The performance of hydronic RPSC system was determined by factoring the influence of building configurations, termed as urban canyon. 3D CFD simulation studies of Standard k-ε RANS model coupled with Solar Load and DO radiation model were carried out to simulate the integration of hydronic RPSC with urban canyons. Validations of the simulation results were done against previous published works and the thesis’ thermal data collections within Kuala Lumpur conurbation centre. Based on the simulation and data collection, it was found that building configurations with symmetrical canyon height had clearly increased the performance of RPSC system in surface temperature reduction and potential temperature collection as compared to other comparative settings. There was an increasing trend by changing the aspect ratio (AR) 1 to AR 2 with a slightly drop in the performance to AR 3 and AR 4 due to shadow effects. Findings from the data collection however, disagreed the trend due to a major factor from the solar intensity of the measured days affecting the temperature values. Furthermore, application of RPSC system in deep street canyons showed the potential of the system to reduce up to 4 °C air temperature at the pedestrian level; however, it was still insufficient to achieve an outdoor comfort temperature level.

According to the report, more than 41% of fatalities in flight were to find to be caused by fire. In recent years, composites used in aircrafts are carbon fibre/ glass fibre reinforced epoxy, due to light weights and high strength properties. However, these composites are known as highly flammable. Serious fire incident will be created in a short time after a spark of fire. Furthermore, ingredients for fibre and epoxies are, toxic and resulting in the release of toxic gases during fire, and cutting off fresh air to survivors and hindering their escape. In the meantime, biopolymers have attracted considerable attention due to their environmentally friendly and sustainable nature, Kenaf Fibre (KF) is one of the most famous natural fibre used as a reinforcement in Polymer Matrix Composites (PMC). Kenaf is also known as Hibiscus Cannabimus L., and is an herbaceous annual plant that is grown in a wide range of weather conditions, growing more than 3 meters within 3 months. However, the inherent drawbacks associated with Floreon (FLO) based composites include brittleness, lower strength and high moisture sensitivity, which in turn limit their application in the aircraft industry. In order to overcome such drawbacks, two modification techniques were employed in this study: (1) incorporated kenaf fibre into polypropylene polymer with magnesium hydroxide flame retardant and (2) reinforces kenaf fibre and magnesium hydroxide by different combination of volume. Consequently, KF reinforced FLO or polypropylene (PP) composites with magnesium hydroxide (MH) flame retardant specimens were successfully developed using extrusion followed by hot pressing. The increment of KF contents in PP composites had shown higher tensile modulus and decomposed mass loss at onset temperature, but lower values in tensile strength, elongation, flexural strength and onset temperature. In the meantime, 25 wt% KF contented PP composite shown a slightly higher flexural strength, while the higher volume of MH filler in composites caused lower strength, tensile modulus, elongation, but with higher onset temperature and the 2nd peak temperature in thermogravimetric analysis (TGA) testing. Furthermore, increasing the KF contents in PP matrix has found lower mass residue. However, increasing of KF contents in MH contented composite had increased the mass residue at the end of the testing. On the other hand, the increment of the melt flow properties (MVR and MFR) was found for the KF or MH insertion, due to the hydrolytic degradation of the polylactic acid (PLA) in FLO. The deterioration of the entanglement density at high temperature, shear thinning and wall slip velocity were the possible causes for the higher melt flow properties. In the meantime, increasing the KF loadings caused the higher melt flow properties while the FLO composites with higher MH contents created stronger bonding for higher macromolecular chain flow resistance, hence, recorded lower melt flow properties. However, the complicated melt flow behavior of the KF reinforced FLO/MH biocomposites was found in this study. The high probability of KF-KF and KF-MH collisions was expected and there were more collisions for higher fibre and filler loading, causing lower melt flow properties. Besides that, insufficient resin for fibre wetting, hydrolytic degradation on the biopolymer and poor interfacial bonding were attributed to low strength profile. Yet, further addition of KF increased the tensile strength and flexural. Nevertheless, inserting KF and MH filler have shown positive outcome on flexural modulus. Insertion of KF and MH showed the deterioration of impact strength, while the addition of KF increased the impact strength. Meanwhile, FLO is a hydrophobic biopolymer which showed only a little of total water absorption. In this regard, for the first 24 hours, the water absorption rates were high for all bio-composites. Hence, it is worth mentioning that the high contents of KF in bio-composites shown higher saturation period and higher total amount of water absorption while MH caused shorter saturation period but lower total amount of water absorption. However, interface bonding incompatibility has increased the water absorption of KF/FLO/MH composites. Moreover, some synergistic effect was located in char formation, Tg reduction and a lower tan δ peak shown in the three-phase system (KF/FLO/MH). The MH filler was found to be more significant in enhancing mass residual. The Tg were show deterioration for all samples compared to pure FLO biopolymer. The melting temperature has found no meaningful change for either insertion of KF or MH or both. The values of co-coefficient, C recorded decreasing as increasing the fibre loading. This showing the fibres transfer the loading effectively. As conclusion, although 10KF5MH specimen does not have the best performance in mechanical properties, a higher flame retardancy shall provide KF reinforced FLO composite with MH filler for more applications in advanced sector especially, in hazardous environment.

With the development of renewable energy, the wind-energy generation is no longer a brand-new field. Considering the complex work environment and huge maintenance fee, windmill detection plays a significant role in the wind industry. Therefore, combining with the application of digital image technology in windmill in recent years, the thesis proposes a new non-destructive detection method based on digital image process algorithms, including Optical Intensity for frequency and cycle time measurement, Frame Difference for motion tracking, and EVM (Eulerian Video Magnification) for invisible motion enhancement.

This thesis uses the Pitzer model to investigate the equilibrium of aqueous species formed after the absorption of CO2 by chemical solvents. Since the parameters in the Pitzer equations are unknown for some species involved in the equilibrium, new expressions that correlate the virial parameters in the Pitzer equations with the ionic radii and charges of the species are derived. Further, since some ionic radii are unavailable in the literature, new expressions are derived to estimate these unknown ionic radii. Furthermore, a case study involving MEA, DEA and NH3 is investigated using the expressions that correlate the parameters in the Pitzer equations with the ionic radii and charges. Finally, a mineral carbonation process involving NH3 as the chemical solvent is simulated in Aspen Plus, and this process aims to investigate the precipitation of calcium carbonate using the fly ash generated in power plants. As a conclusion, the calculated activity and osmotic coefficients of the aqueous species obtained using the equations that correlate the virial coefficients in the Pitzer equations with the ionic radii and charges are in good agreement with the experimental data from the literature up to a temperature 150 °C. Likewise, the expressions derived to estimate the unknown ionic radii produces results that are in good agreement with the literature data. Furthermore, the case study involving MEA, DEA and NH3 shows that the correlating equations accurately predict speciation and partial pressures up to a solvent mass fraction of about 20%. Finally, a comprehensive analysis involving the conversion of the pure CO2 produced in the amine capture plants into a solid is presented, and as a result this new process is capable not only of reducing the electricity consumption of the MEA capture plant by about 18%, but also to produce a product that may be potentially reutilized in industry, namely the PCC.

Experimental characterisation of tissue deformations associated with penetrating impact of fragments from explosive devices is challenging. Whereas experiments involving ballistic gelatine tissue simulants enable direct visualisation of deformation patterns, quantification of these deformations remains difficult. This thesis investigates the use of image registration for this purpose. Image registration methods optimise alignment of corresponding structures in image pairs, and in the process estimate the deformation fields that best achieve this. In the current context, it is hypothesised that registration of consecutive images from videos of gelatine penetration events can enable the corresponding gelatine deformation fields to be estimated. Three main activities were undertaken towards validation of this hypothesis: the proposed registration approach was tested on a series of synthetic images emulating the types of deformations expected in penetration events; the approach was then tested on images derived from a carefully controlled indentation experiment, in which a block of gelatine was deformed quasi-statically with a rigid indenter while the resulting deformation was filmed; and finally it was tested on video footage from projectile penetration experiments, in which metal projectiles were fired into blocks of gelatine and filmed with a high speed video camera. A series of complementary studies was also undertaken in support of these experiments. Firstly, to better understand the parameters of real penetration scenarios, the fragment generation and flight behaviour of a typical explosive device were analysed. Secondly, to improve understanding of the material behaviour of the test gelatine, mechanical characterisation tests were undertaken, and a visco-hyperelastic constitutive model was proposed. The individual registration operations themselves appeared to perform well, in the sense that initially disparate consecutive image pairs were brought into good alignment. However, composition of the corresponding transformation fields, necessary for tracking accumulated deformations over the course of a video sequence, was found to yield artefacts and unphysical deformation estimates in some cases. These were judged to result both from deficiencies in the methods themselves, and flaws in the experimental arrangements. Therefore, while the proposed registration approach appears to show promise, further work is needed to establish its validity conclusively. The thesis closes with a discussion of possible approaches to the latter.

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The undamped vibration response of a single degree of freedom system with a hardening non-linear spring is investigated for the case of a centrifugal disturbing force. The restoring force characteristic is asymmetrical. The degree of asymmetry is expressed in terms of the parameter of static deflection, which is produced by the weight of the vibrating mass. The approximate method of Ritz-Galerkin is used for the theoretical analysis. On the basis of published literature this method appears to be generally superior to other analytic methods, and this is supported in this investigation by a direct comparison of theoretical results for the case of free vibration. Experimental results are obtained by means of an electronic analogue computer. Free vibration, harmonic resonance, superharmonic resonance of order 2, and subharmonic resonance of order 1/2 are investigated for several magnitudes of the static deflection and of the disturbing force amplitude. It is found that in general the static deflection, or the force of gravity, has a considerable effect on the vibration response and hence cannot be neglected in a theoretical analysis. The superharmonic resonance is practically negligible even at small magnitudes of damping. In contrast the subharmonic resonance is very pronounced, and from the practical point of view it is at least as important as the harmonic resonance. Theoretical results obtained by means of the Ritz-Galerkin method compare favourably with experimental results. The error of approximation increases slightly with the magnitude of non- linearity, but in the range of the investigation it remains within acceptable limits.