Application of the actuator disc theory of Delft3D-FLOW to model far-field hydrodynamic impacts of tidal turbines

Abstract

Accurate knowledge of tidal turbine impacts on the far-field hydrodynamic conditions, which extend from 3 to 20 diameters downstream the turbine, is essential for the estimation of tidal resource, farm layout design and environmental impact. For this purpose, tidal turbine operation is modelled within coastal models, as enhanced bottom friction, or momentum sinks. In Delft3D-FLOW, a state-of-the-art coastal model, turbine operation is usually represented via momentum losses, using the Porous Plate tool. However, the Porous Plate tool presents significant limitations to accurately represent energy extraction and geometry of tidal turbines. Recently, a new tool (Actuator Disc) based on the Momentum Actuator Disc Theory (MADT) was developed in Delft3D-FLOW, overcoming the aforementioned limitations and showing excellent results against laboratory data. The aim of this work is to compare the behaviour of the Actuator Disc and Porous Plate on the far-field hydrodynamics. Overall, significant differences were found, with the Porous Plate significantly underestimating the impact on instantaneous and residual flow velocities and turbulence conditions, when the turbine operates at its rated power. Consequently, MADT appears as the best alternative to investigate the far-field hydrodynamic impacts of tidal turbine operation and previous research based on the Porous Plate tool should be revisited.

Análisis de los efectos de la descarga del canal del dique sobre la estratificación salina de su desembocadura a la bahía de Cartagena

“…El modelo hidrodinámico Delft3D ha sido ampliamente usado en el ámbito mundial para el estudio de estos tipos de sistemas [20], [21], [22], [23], [24], [25], [26], mostrando su robustez desde condiciones promedio o típicas, hasta eventos extremos, lo que se confirma con los resultados del presente trabajo, que muestran un porcentaje de correlación alto 97% con respecto a las variables de salinidad y niveles de marea. Entre los estudios internacionales en los que se ha usado este software, se encuentra [27] en el estuario de Yangtsé en China, en donde se analizó la interacción flujo-sedimento en los perfiles verticales dentro de la zona de máxima turbidez (TMZ), obteniendo además las corrientes verticales y cómo estas afectan la instrucción salina mediante el modelo hidrodinámico Delft3D.…”

Modeling Morphodynamic Impacts and Optimization of Marine Hydrokinetic Arrays in Shallow Offshore Environments

“…In our review, we will primarily focus on similar numerical simulations. Within these numerical models, the device is typically represented as an energy absorption object, with its physical structure often omitted within the model domain [8][9][10][11].…”

“…A comparative analysis of different approaches for incorporating momentum sinks derived from Marine Hydrokinetic (MHK) technologies in Delft3D-FLOW revealed that utilizing an actuator disc tool (based on the Momentum Actuator Disc) produced more realistic far-field flow velocities than the Porous Plate tool. In both methods, the estimation of momentum loss terms relies on the thrust coefficient of the turbines, as established by Ramos [10].…”

A Deep Learning Model Using Satellite Ocean Color and Hydrodynamic Model to Estimate Chlorophyll-a Concentration

“…A hydrodynamic model was used to generate marine physical factors, such as the currents, water level, salinity, and temperature, in the study area. The Delft 3D model, which has been applied in several research areas, was used to simulate three-dimensional hydrodynamics [41][42][43][44]. The model domain extended for 58 km along the north-south direction and 53 km along the east-west direction, to sufficiently cover the study area.…”