Preliminary Design of Floating Point Absorber Offshore Rio de Janeiro

2015 ◽  
Author(s):  
Milad Shadman ◽  
Segen F. Estefen ◽  
Claudio Alexis Rodriguez Castillo ◽  
Marcelo I. Lourenço
Keyword(s):  
Rio De Janeiro ◽  
Reference Site ◽  
Numerical Models ◽  
Electrical Power ◽  
Optimization Procedure ◽  
Wave Climate ◽  
Floating Point ◽  
Concept Design ◽  
Climate Conditions ◽  
Point Absorber

The Rio floating point absorber (FPA) is designed for a reference site located near an island offshore Rio de Janeiro. According to the reference site characteristics, a two-body floating point absorber concept design is chosen to convert ocean wave energy into electrical power. An innovative procedure aiming at finding an optimal shape adapted to predefined wave climate conditions, using the Design of Experiments (DOE) method, is applied. A simple linear damper model is used to represent the Power Take-Off (PTO) mechanism. The optimization procedure is divided into Buoy and support (spar/plate) steps, so the optimized buoy is determined first and then a proper support is determined to reach a satisfactory two-body FPA system. The nonlinearities are not considered in this study and linear Numerical models are developed using AQWA/ANSYS and Minitab software in frequency domain. Finally, a preliminary optimized model of the two-body FPA is determined in accordance with the particular sea site information of the Rio de Janeiro.

scholarly journals Wave-to-Wire Model Development and Validation for Two OWC Type Wave Energy Converters

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3977 ◽  
Author(s):  
Pierre Benreguig ◽  
James Kelly ◽  
Vikram Pakrashi ◽  
Jimmy Murphy
Keyword(s):  
Wave Energy ◽  
Numerical Models ◽  
Power Conversion ◽  
Electrical Power ◽  
Model Development ◽  
Wave Structure ◽  
Experimental Tests ◽  
Wave Climate ◽  
Type Wave ◽  
Conversion Stage

The Tupperwave device is a closed-circuit oscillating water column (OWC) wave energy converter that uses non-return valves and two large fixed-volume accumulator chambers to create a smooth unidirectional air flow, harnessed by a unidirectional turbine. In this paper, the relevance of the Tupperwave concept against the conventional OWC concept, that uses a self-rectifying turbine, is investigated. For this purpose, wave-to-wire numerical models of the Tupperwave device and a corresponding conventional OWC device are developed and validated against experimental tests. Both devices have the same floating spar buoy structure and a similar turbine technology. The models include wave-structure hydrodynamic interaction, air turbines and generators, along with their control laws in order to encompass all power conversion stages from wave to electrical power. Hardware-in-the-loop is used to physically emulate the last power conversion stage from mechanic to electrical power and hence validate the control law and the generator numerical model. The dimensioning methodology for turbines and generators for power optimisation is explained. Eventually, the validated wave-to-wire numerical models of the conventional OWC and the Tupperwave device are used to assess and compare the performances of these two OWC type wave energy device concepts in the same wave climate. The benefits of pneumatic power smoothing by the Tupperwave device are discussed and the required efficiency of the non-return valves is investigated.

scholarly journals Thermal-Structural Design of Actively-Cooled Panels Reinforced by Light-Weight Truss Cores

2013 ◽  
Author(s):  
Hongwei Song ◽  
Mingjun Li ◽  
Chenguang Huang ◽  
Xi Wang
Keyword(s):  
Heat Transfer ◽  
Structural Analysis ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Thermal Environment ◽  
Numerical Models ◽  
Lightweight Design ◽  
Optimization Procedure ◽  
Combustion Gas ◽  
Design Variables

This paper focuses on thermal-structural analysis and lightweight design of actively-cooled panels reinforced by low density lattice-framed material (LFM) truss cores. Numerical models for actively-cooled panels are built up with parametric codes to perform the coupled thermal-structural analysis, considering the internal thermal environment of convective heat transfer in the combustor and convective heat transfer in the cooling channel, and internal pressures from the combustion gas and the coolant. A preliminary comparison of the LFM truss reinforced actively-cooled panel and the non-reinforced panel demonstrates that the thermal-structural behavior is significantly improved. Then, an optimization procedure is carried out to find the lightest design while satisfying thermal deformation and plastic strain constraints, with thicknesses of face sheets and topology parameters of LFM truss as design variables. The optimization result demonstrates that, compared with the non-reinforced actively-cooled panels, weight reduction for the panel reinforced by LFM truss may reach 19.6%. We have also fabricated this type of actively-cooled panel in the laboratory level, and the specimen shows good mechanical behaviors.

scholarly journals rpe v5: An emulator for reduced floating-point precision in large numerical simulations

2016 ◽  
Author(s):  
Andrew Dawson ◽  
Peter Düben
Keyword(s):  
Numerical Simulations ◽  
Climate Models ◽  
Numerical Models ◽  
Computational Cost ◽  
Floating Point ◽  
Climate Modelling ◽  
Acceptable Quality ◽  
Weather And Climate ◽  
Code Changes ◽  
Numerical Precision

Abstract. This paper describes the rpe library which has the capability to emulate the use of arbitrary reduced floating-point precision within large numerical models written in Fortran. The rpe software allows model developers to test how reduced floating-point precision affects the result of their simulations without having to make extensive code changes or port the model onto specialised hardware. The software can be used to identify parts of a program that are problematic for numerical precision and to guide changes to the program to allow a stronger reduction in precision. The development of rpe was motivated by the strong demand for more computing power. If numerical precision can be reduced for an application under consideration while still achieving results of acceptable quality, computational cost can be reduced, since a reduction in numerical precision may allow an increase in performance or a reduction in power consumption. For simulations with weather and climate models, savings due to a reduction in precision could be reinvested to allow model simulations at higher spatial resolution or complexity, or to increase the number of ensemble members to improve predictions. rpe was developed with particular focus on the community of weather and climate modelling, but the software could be used with numerical simulations from other domains.

scholarly journals Applications of Models and Tools for Mesoscale and Microscale Thermal Analysis in Mid-Latitude Climate Regions—A Review

2021 ◽  
Vol 13 (22) ◽  
pp. 12385
Author(s):  
Gabriele Lobaccaro ◽  
Koen De Ridder ◽  
Juan Angel Acero ◽  
Hans Hooyberghs ◽  
Dirk Lauwaet ◽  
...  
Keyword(s):  
High Temperatures ◽  
Numerical Models ◽  
Spatial Scales ◽  
Built Environments ◽  
Local Climate ◽  
Climate Conditions ◽  
The Social ◽  
Climatic Environment ◽  
Intense Solar Radiation ◽  
Mobile Measurements

Urban analysis at different spatial scales (micro- and mesoscale) of local climate conditions is required to test typical artificial urban boundaries and related climate hazards such as high temperatures in built environments. The multitude of finishing materials and sheltering objects within built environments produce distinct patterns of different climate conditions, particularly during the daytime. The combination of high temperatures and intense solar radiation strongly perturb the environment by increasing the thermal heat stress at the pedestrian level. Therefore, it is becoming common practice to use numerical models and tools that enable multiple design and planning alternatives to be quantitatively and qualitatively tested to inform urban planners and decision-makers. These models and tools can be used to compare the relationships between the micro-climatic environment, the subjective thermal assessment, and the social behaviour, which can reveal the attractiveness and effectiveness of new urban spaces and lead to more sustainable and liveable public spaces. This review article presents the applications of selected environmental numerical models and tools to predict human thermal stress at the mesoscale (e.g., satellite thermal images and UrbClim) and the microscale (e.g., mobile measurements, ENVI-met, and UrbClim HR) focusing on case study cities in mid-latitude climate regions framed in two European research projects.

scholarly journals Analysis of the influence of ENSO phenomena on wave climate on the central coastal zone of Rio de Janeiro (Brazil)

2015 ◽  
Vol 15 (3) ◽  
pp. 353-370 ◽  
Author(s):  
Nair Emmanuela da Silveira Pereira ◽  
Leonardo Azevedo Klumb-Oliveira
Keyword(s):  
Coastal Zone ◽  
Rio De Janeiro ◽  
Wave Climate

Experimental Full-Scale Test Cell Optimizing for Research of Novel Concepts towards Climatically Active Solar Façade Design

2016 ◽  
Vol 861 ◽  
pp. 213-220 ◽  
Author(s):  
Miroslav Čekon ◽  
Richard Slávik ◽  
Karel Struhala ◽  
Marian Formánek
Keyword(s):  
Numerical Models ◽  
Test Methods ◽  
Full Scale ◽  
Test Cell ◽  
Full Scale Test ◽  
Climate Conditions ◽  
Outdoor Climate ◽  
Research Activities ◽  
Building Components ◽  
Scale Test

The passive solar test facilities have recently been created in many research centers all over the world to analyse dynamic outdoor phenomena on buildings and their components. The main objective of these research activities is primarily to evolve a methodology, improve test methods, validate numerical models and measure real thermodynamic properties of building components under outdoor climate conditions. An integration of advanced material solutions into buildings need to be investigated within specific conditions related specifically to outdoor test methods. A research project on Contemporary concepts of climatically active solar facades at the Brno University of Technology does have an ambition to create an experimental full-scale test cell for research of thermal aspects in progressive advances of future solar façade concepts exposed to the real climate conditions. This paper describes the design optimization phase preceding the test cell assembly. This phase includes the analysis of energy and thermal properties based on parametric study features. Computer simulations based on finite element and volume methods are involved in the optimization process. The proposed optimized test cell design is confronted with parametrization of typical thermal aspects to present final test cell demonstration.

Cable JIP: A Research Project to Assess the Feasibility of a Semi-Static Electrical Subsea Cable for the Power Take-off from a TLP-type Floating Offshore Wind Turbine

2021 ◽  
Author(s):  
J. J. de Wilde ◽  
C. G. J. M. van der Nat ◽  
L.. Pots ◽  
L. B. de Vries ◽  
Q.. Liu
Keyword(s):  
Wind Turbine ◽  
Numerical Models ◽  
Electrical Power ◽  
Offshore Wind ◽  
Offshore Wind Turbine ◽  
Power Cable ◽  
Test Case ◽  
Research Project ◽  
Floating Offshore Wind Turbine ◽  
Cost Of Energy

Abstract CABLE JIP research project in 2017-2019 was initiated with the aim of studying the feasibility of deploying a novel semi-static electrical cable for the power take-off from a TLP-type Floating Offshore Wind Turbine (FOWT). Today, expensive dynamic electrical cables are mainly used for the power take-off from demonstrator project FOWTs or from new FOWTs on the drawing board. For a TLP-type FOWT, the use of a semi-static electrical power cable instead of a fully dynamic electrical power cable (umbilical) is an attractive option to reduce the levelized cost of energy (LCoE). However, the electrical power cable in a dynamic offshore environment is vulnerable to failure, either at the floater side or at the seabed touchdown area. Moreover, the electrical power cable for power take-off is typically non-redundant, while the availability of the turbine(s) highly depends on this critical component to transport the produced power to the substation. The paper discusses the results of the CABLE JIP research project, with focus on the verification and calibration of the numerical models for the ULS and FLS assessment of the electrical power inter-array cable for a harsh weather test case with a TLP-type floating offshore wind turbine in 96.5 m water depth.

scholarly journals Wave Climate at Shallow Waters along the Abu Dhabi Coast

Water ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 985 ◽  
Author(s):  
Waleed Hamza ◽  
Letizia Lusito ◽  
Francesco Ligorio ◽  
Giuseppe Tomasicchio ◽  
Felice D’Alessandro
Keyword(s):  
Shallow Water ◽  
Numerical Models ◽  
Grid Point ◽  
Arabian Gulf ◽  
Acoustic Doppler Current Profiler ◽  
Wave Climate ◽  
Abu Dhabi ◽  
Water Conditions ◽  
Key Factor ◽  
Offshore Wave

High-resolution, reliable global atmospheric and oceanic numerical models can represent a key factor in designing a coastal intervention. At the present, two main centers have the capabilities to produce them: the National Oceanic and Atmospheric Administration (NOAA) in the U.S.A. and the European Centre for Medium-Range Weather Forecasts (ECMWF). The NOAA and ECMWF wave models are developed, in particular, for different water regions: deep, intermediate, and shallow water regions using different types of spatial and temporal grids. Recently, in the Arabian Gulf (also named Persian Gulf), the Abu Dhabi Municipality (ADM) installed an ADCP (Acoustic Doppler Current Profiler) to observe the atmospheric and oceanographic conditions (water level, significant wave height, peak wave period, water temperature, and wind speed and direction) at 6 m water depth, in the vicinity of the shoreline of the Saadiyat beach. Courtesy of Abu Dhabi Municipality, this observations dataset is available; the recorded data span the period from June 2015 to January 2018 (included), with a time resolution of 10 min and 30 min for the atmospheric and oceanographic variables, respectively. At the ADCP deployment location (ADMins), the wave climate has been determined using wave propagation of the NOAA offshore wave dataset by means of the Simulating WAves Nearshore (SWAN) numerical model, the NOAA and ECMWF wave datasets at the closest grid point in shallow water conditions, and the SPM ’84 hindcasting method with the NOAA wind dataset used as input. It is shown that the best agreement with the observed wave climate is obtained using the SPM ’84 hindcasting method for the shallow water conditions.

Wave Climate Off Rio de Janeiro

1989 ◽  
Author(s):  
Maria Helena Severo de Souza ◽  
Carlos Eduardo Parente Ribeiro
Keyword(s):  
Rio De Janeiro ◽  
Wave Climate
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