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This research study develops the design and model of a Solar Organic Rankine Cycle (SORC) coupled to a bio-digester for small-scale generation in rural areas, in Betulia, Colombia. Moreover, the model is optimised employing a Genetic Algorithm with the software Matlab and the thermodynamic library CoolProp. The objective variables were the mass flow rate of the working fluid, the pressure and temperature of the expander inlet, the solar collectors’ type and the temperature of the water circuit for the bio-digester. The results indicate an overall efficiency between 8.42 and 9.45% with a Levelized Cost of Energy (LCE) between 3.85 and 5.63 £/W. Additionally, the power output is directly related to the mass flow rate of the working fluid. Likewise, increasing the scale of the SORC decreases the LCE. Finally, the results suggest that a superheated fluid reduces the efficiency and the LCE and can deliver more heat to the bio-digester. It is advisable the utilisation of a scroll expander and a counter-flow plate exchanger with a Direct Vapour Generation configuration. The model is a flexible tool capable of integrating more equations and components, with the evaluation of different fitness functions.

Swirl flows have been used lately for the modern gas turbine combustion to enhance the mixing and flame stabilization. Instabilities that occur due to such flow are often termed as precessing vortex core (PVC). This precessing vortex core has a greater effect on the flow characteristics and heat release and its interaction with the flame is important. The numerical analysis using Reynolds-Averaged Navier-Stokes (RANS) and Large Eddy Simulation (LES) turbulence models were used to carry out simulations of gas turbine combustor to study the PVC and flame interaction in the flow fields. The boundary conditions were set as power output – 35 kW, Reynolds number - 52000 and the equivalence ratio - 0.65. The RANS results were more similar to the experimental one than the LES. The LES results were more useful in studying the PVC characteristics, PVC-flame interaction and instantaneous flow field. The RANS results were helpful in understanding the average flow fields. The grid requirement for both turbulence models and their importance was also studied.

In this study, we have developed an optimization procedure for diesel engine downsizing with application of biofuels. The analysis was performed using the specialist thermodynamic software to simulate combustion and emission characteristics of an internal combustion engine. A JCB 165 kW Diesel Max commercial nonroad diesel engine has been selected for the project. The performance characteristics of this engine were set as reference. The results for the original engine and downsized engine were compared. The engine performance and emission characteristics with diesel fuel, different blends of soybean methyl ester (SME) and rapeseed methyl ester (RME) have been investigated. The obtained results showed that it was possible to achieve equal level of break power and torque for 50%-downsized engine as compared with those of the original engine. The results over different engine speeds and loads showed around 4-11% reduction range in fuel consumption, 4-11% reduction range in CO2 emissions and about 86-99% reduction range in PM emissions. However, the NOx emissions significantly increased. Further to decrease NOx emission level the exhaust gas recirculation (EGR) was applied.

Wave energy exploits the movement of the wind across the surface of the sea to provide an inexhaustible, carbon-free energy source for electricity generation. This can potentially provide a significant contribution to electricity generation supply in the UK, meeting up to 20% of the UK’s electricity demand. This represents 30-50 MW capacity of electrical energy by 2020, and potentially 27 GW by 2050 as technology within the industry develops and matures. Studies show that developing marine energy resources in the UK can save 60 metric tons of carbon dioxide by 2025 and aid in the UK meeting 20-20-20 renewable energy objectives. In this paper the design of a wave power station integrated with a decommissioned offshore oil platform is proposed. This approach provides ideal conditions for the exploitation of wave energy for electricity generation. It not only saves the cost of decommissioning but also provides the offshore oil platform with new life, generating electrical energy from an inexhaustible source. The objective of this work was to conduct an extensive feasibility study to develop a proof of concept design for wave energy generation integrated with an offshore oil platform.

Combustion and Exhaust Emission Characteristics of Diesel Micro-Pilot Ignited Dual-Fuel Engine