Browsing College of Engineering and Informatics by Author "Nash, Stephen"
Now showing items 1-20 of 38
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Adaptive Mesh Multi-Scale Modelling of Tidal Hydraulics and Material Transport
Nash, Stephen; Hartnett, Michael (2011)Multi-scale modelling for structured meshes is achieved by nesting high resolution grids within lower resolution grids. By specifying high resolutions in areas of interest only, computational cost can be reduced. Adaptive ... -
An adaptive mesh solute transport model
Nash, Stephen; Hartnett, Michael (2009)An adaptive mesh solute transport model is presented. The adaptive mesh scheme is implemented in a one-way multiply nested version of the hydrobiological model DIVAST (Depth Integrated Velocity and Solute Transport). The ... -
Application of water quality index models to an Irish estuary
Uddin, Md Galal; Nash, Stephen; Olbert, Agnieszka Indiana (Civil Engineering Research Association of Ireland (CERAI), 2020-08-27)The paper investigates the application of different Water Quality Index (WQI) models for to estuarine waters. WQI models are aggregation based mathematical models that convert extensive water quality data into a single ... -
Assessment of water quality using Water Quality Index (WQI) models and advanced geostatistical technique
Uddin, Md Galal; Olbert, Agnieszka Indiana; Nash, Stephen (Civil Engineering Research Association of Ireland (CERAI), 2020-08-27)Water quality index (WQI) models are popular tools to evaluate the quality of water; as such they have been developed and used by many agencies worldwide. However, the WQI model may generate excessive uncertainties in ... -
A CFD investigation of a variable-pitch vertical axis hydrokinetic turbine with incorporated flow acceleration
Mannion, Brian; McCormack, Vincent; Leen, Sean B.; Nash, Stephen (Springer, 2019-02-18)This paper presents the numerical modelling of a novel vertical axis tidal turbine that incorporates localised flow acceleration and variable-pitch blades. The focus is to develop a computational fluid dynamics model of a ... -
Development and assessment of a blade element momentum theory model for high solidity vertical axis tidal turbines
Mannion, Brian; Leen, Sean B.; Nash, Stephen (Elsevier, 2020-01-20)Tidal energy is an attractive renewable resource given its predictability. The production of reliable, efficient and cost-effective tidal energy turbines requires the development of computer models for assessment and design ... -
Development of a nested coastal circulation model: boundary error reduction
Nash, Stephen; Hartnett, Michael (Elsevier, 2014-03)Numerical models have a valuable role to play in the sustainable management of coastal waters but accurate simulation of land/sea interactions, particularly in areas of complex coastlines, requires the use of high spatial ... -
Development of high-resolution multi-scale modelling system for simulation of coastal-fluvial urban flooding
Comer, Joanne; Olbert, Agnieszka Indiana; Nash, Stephen; Hartnett, Michael (Copernicus Publications, 2017-02-16)Urban developments in coastal zones are often exposed to natural hazards such as flooding. In this research, a state-of-the-art, multi-scale nested flood (MSN_Flood) model is applied to simulate complex coastal-fluvial ... -
The effects of array configuration on the hydro-environmental impacts of tidal turbines
Fallon, David; Hartnett, Michael; Olbert, Agnieszka Indiana; Nash, Stephen (Elsevier, 2014-04)The economic viability of tidal turbines will require the deployment of multiple devices in array formations in a manner analogous to wind farms. This research investigates the effects of the configuration of a tidal turbine ... -
The effects of array configuration on the hydro-environmental impacts of tidal turbines.
Fallon, David; Nash, Stephen (2012)Tidal stream turbines provide a technically viable means of generating electricity from a sustainable resource; however, economic viability will require the deployment of multiple devices in array formations in a manner ... -
An experimental study of a flow-accelerating hydrokinetic device
Mannion, Brian; McCormack, Vincent; Kennedy, Ciaran; Leen, Sean B.; Nash, Stephen (SAGE Publications, 2018-05-01)Tidal energy researchers and developers use experimental testing of scaled devices as a method of evaluating device performance. Much of the focus to date has been on horizontal axis turbines. This study is focused on a ... -
Galway Bay bathymetry comparison from Admiralty Chart and LiDAR datasets.
Fallon, David; Nash, Stephen (2012)The primary objective of this paper was to test the sensitivity of numerical models to bathymetry datasets. Bathymetric datasets used were from; 1) Admiralty Charts and 2) LiDAR & Multi- Beam Echo Sounder surveys. The ... -
High-resolution multi-scale modelling of coastal flooding due to tides, storm surges and rivers inflows: A Cork city example
Olbert, Agnieszka Indiana; Comer, Joanne; Nash, Stephen; Hartnett, Michael (Elsevier, 2017-01-31)This paper demonstrates the capability of a new state-of-the-art flood modelling system consisting of multiple nested models to simulate urban coastal flood inundation. A flood event in Cork City, Ireland which occurred ... -
Hydrodynamic modelling approaches to assess mechanisms affecting the structural performance and maintenance of vortex drops shaft structures
Carty, Alan; O’Neill, Colin; Nash, Stephen; Clifford, Eoghan; Mulligan, Sean (Taylor & Francis, 2019-07-29)Vortex drop shafts, a key hydraulic structure within modern day deep sewer conveyance systems, must be designed structurally to sustain performance and longevity of operating life under very energetic loading conditions. ... -
An integrated approach to trophic assessment of coastal waters incorporating measurement, modelling and water quality classification
Hartnett, Michael; Nash, Stephen; Olbert, Agnieszka Indiana (2012)Various protocols have been developed for trophic assessment of coastal waters but most incorporate single value compliance criteria for water quality parameters which, in reality, exhibit significant spatial variation. ... -
Interactions, mechanisms and impact of future coastal urban flooding. A case study of Cork city
Kirkpatrick, Jennifer Isabel Munro; Nash, Stephen; Hartnett, Michael; Comer, Joanne; Olbert, Agnieszka Indiana (Hydrology Ireland, 2020-11-17)In coastal floodplains, high river flows and high coastal water levels can result in extensive flooding. Mechanisms of flooding play a crucial role in flood characteristics with distinctive differences in flood wave ... -
Irish estuaries: Water quality status and monitoring implications under the water framework directive
Hartnett, Michael; Nash, Stephen (2011)The status of water quality of Irish estuaries is reviewed; this sheds light on the rationale behind the design of the national monitoring programme. Relative to other EU Member States, Ireland's coastal monitoring programme ... -
Mechanisms of flooding in Cork City
Olbert, Agnieszka Indiana; Comer, Joanne; Nash, Stephen; Hartnett, Michael (International Association of Hydrological Sciences, 2015-11-17)Flooding is one of the most frequent and devastating natural disasters. Many urban developments are located in estuaries where river flow and sea water merge. Cork City situated in the River Lee estuary frequently subject ... -
Modelling nutrient and chlorophyll_a dynamics in an Irish brackish waterbody
Hartnett, Michael; Nash, Stephen (Elsevier, 2004-01)This paper presents aspects of a research investigation into nutrient fluxes into and out of an important Irish estuary, Wexford Harbour, located in the southeast of Ireland. Details of the methodology applied, the data ... -
Modelling nutrients and chlorophyll-a dynamics in an Irish brackish waterbody
Hartnett, Michael; Nash, Stephen (Elsevier, 2004)This paper presents aspects of a research investigation into nutrient fluxes into and out of an important Irish estuary, Wexford Harbour, located in the southeast of Ireland. Details of the methodology applied, the data ...