Simultaneous advancements in high-performance computing technologies (HPC) and fluid dynamics science have set the stage for practical computational fluid dynamics (CFD) modelling of complex real-life problems including fluid-structure interaction. The presented research summarizes the capabilities of the OpenFOAM CFD toolbox to facilitate design optimization of an innovative tidal energy device. Numerical simulations were conducted for different environmental conditions and operating scenarios to characterize the flows through the device. The influence of changing the number of turbine blades as well as their submergence depth in the incident flow was tested through a series of 2D numerical simulations which consider the dynamics of the rotary component of the system. The results of the simulations were used to investigate potential strategies for design optimization, ultimately improving efficiency.
Diminishing fossil fuel resources, and an increased understanding of the environmental impacts associated with fossil fuel power generation, has brought increasing attention to renewable energy resources such as hydro power. Water wheels are one of the oldest forms of hydropower conversion technologies and have historically been used to extract energy from stream flows (Poncelet, 1843). In general, there are four types of water wheels: undershot, overshot, breast-shot, and stream water wheels. Detailed information about each type of water wheel and their characteristics can be found in references Nguyn et al. (2018), and Tevata and Inprasit (2011). Stream water wheels (Fig. 1) are mainly used for harnessing energy from surface flows and are generally regarded as eco-friendly devices owing to their relatively low impact on the ambient environment. Recent improvements in the efficiency of water wheel systems has motivated their application as a means for generating electricity for remote sites that are isolated from large-scale transmission networks (Bozhinova et al., 2013).
The performance and efficiency of a water wheel system depends on a number of different factors including, for example: the capability of the wheel to extract and transfer the available hydrokinetic energy in the ambient flow to the wheel shaft, the performance of the power take-off system, and the structural resilience of system components. Previous research has been conducted on the development and optimization of water wheel systems using analytical, numerical, and experimental approaches. In general, the main objective of previous research has been to inform design optimization in such a manner that maximizes energy extraction and minimizes construction and maintenance costs. Some studies have investigated design of the platform which the wheel is mounted on (Baker et al., 2015; Batten and Batten, 2015), and others have focused on the wheel characteristics such as the number of blades and their shape (Tevata and Inprasit, 2011; Quaranta and Revelli, 2015; Vidali et al., 2016; Quaranta and Revelli, 2016).
