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The placement of tidal turbines in a tidal farm is challenging owing to the flow resistance caused by individual devices. To successfully deploy tidal turbines, the wake interaction between devices, often determined by the array's layout and spacing, must be understood. In this study, the impact of array configuration for shallow water application is examined numerically using computational fluid dynamics (CFD). This is to propose a suitable array structure for possible implementation in Malaysia. This numerical study uses 15 turbines in a staggered and squared array with two sets of lateral and longitudinal spacing combinations. The horizontal axis tidal turbine (HATT) and vertical axis tidal turbine (VATT) are represented using disc and cylindrical models, respectively. The VATT with staggered setup and greater spacing model demonstrates faster wake recovery (between 10% to 21%), compared to the squared arrangement. This meets the far wake criteria and reduces the chance of wake mixing. It is also suitable for shallow depth implementation.

Towards modernisation of the technological era, electricity demands have been an issue. Although the supply of electrical energy from the renewable sources are increasing, it is still not sufficient to offset the carbon production. Malaysia as a developing country needs ample of supply of electrical energy. As most of the current electrical energy for the country are being produced by non renewable sources, the Malaysian government have started looking into renewable options to produce electrical energy. There are various sources of energy that are available in Malaysia such as solar, natural gas, petroleum, ocean energy and many more. This paper is focused on the tidal energy which is an ocean energy that can produce electrical energy by using the power of tide. This research explores the hybrid turbine design which is a type of vertical-axis tidal turbine that combines two distinct type of devices, namely Savonius and H-Darrieus turbines. Hybrid turbine is useful as it helps to overcome the limitation of individual turbine and also be able to produce energy at a low water velocity. Numerical analysis is employed to investigate the wake recovery behaviour and turbulent mixing due to the positioning of the device using Ansys CFD Fluent. By understanding the general wake characteristics produced by each device, proper planning can be done to configure these devices in an array for future planning. The simulation result shows that the hybrid turbine utilising NACA0015 and NACA0018 with nested configuration demonstrates faster velocity recovery compared to NACA0021. The turbulence wake results also provides a promising output which shows the acceleration of flow at the downstream region for hybrid nested NACA0015 and NACA0018 are more narrow compared to NACA0021. The result of this simulation has also been validated with published data. In a nutshell, the NACA blade design not only affects the performance of the turbine but can also influence the velocity recovery downstream of the device.

Tesla turbine is a bladeless turbine that uses a set of discs arranged at a certain distance to rotate and one of the parameters controlling turbine performance is the inlet parameter. The purpose of this study is to optimize the design of the inlet nozzle and analyse its effects on the flow of the fluid. A total of four nozzle designs have been proposed using CATIA while the Solidworks Flow Simulator is used to analyse the fluid flow at various inlet velocities. Then, the most efficient design is then fabricated via 3D printing and put to test by connecting it with the actual Tesla turbine model. Through the results obtained from the analysis, it is observed that Design 4 is the most efficient of all tested nozzles and the highest RPM and output voltage achieved from the nozzle is 7940 RPM and 13.56 V. The difference in velocity and pressure increases as the area of the nozzle outlet reduces, whereas nozzle efficiency decreases as the inlet velocity increases. The result of this study is a source material for increasing the effectiveness of an alternative power turbine in generating electricity by manipulating the inlet design geometry.

The boundary layer turbine known as Tesla Turbine invented long ago but has failed to be commercialized and replaced by bladed turbines. In this paper, two new techniques for improving the turbine have been proposed. A test model of the proposed boundary layer turbine has been fabricated made and tested under different conditions. The design process includes producing a virtual design and simulation of the turbine using computer software. The proposed designs were fabricated and then tested to analyse results such as speed produced, power produced, and the turbine efficiency. From this study, the proposed turbine designs manage to achieve 18% and 69% efficiency. The findings of this study will serve as a reference for future studies in the generation of power through an alternative powered driven turbine.