Hydrologic data generally consist of a sequence of observations of some phase of the hydrologic cycle made at a particular site. The data may be a record of the discharge of a stream at a particular place, or it may be a record of the amount of rainfall caught in a particular rain gage.
Although for most hydrologic purposes a long record is preferred to a short one, the user should recognize that the longer the record the greater the chance that there has been a change in the physical conditions of the basin or in the methods of data collection. If these are appreciable, the composite record would represent only a nonexistent condition and not one that existed either before or after the change. Such a record is inconsistent.
Hydrologic data generally consist of a sequence of observations of some phase of the hydrologic cycle made at a particular site. The data may be a record of the discharge of a stream at a particular place, or it may be a record of the amount of rainfall caught in a particular rain gage.
Although for most hydrologic purposes a long record is preferred to a short one, the user should recognize that the longer the record the greater the chance that there has been a change in the physical conditions of the basin or in the methods of data collection. If these are appreciable, the composite record would represent only a nonexistent condition and not one that existed either before or after the change. Such a record is inconsistent.
Quick tutorial of how to conduct a bridge scour computation within HECRAS. Characteristics of stream stability fundamentals are also discussed. Abutment, pier, and contraction methodologies from HEC 18 are summarized. Tips to avoid common mistakes are provided. Helpful data sources to assist design are suggested.
DSD-INT 2018 From global to local: Volvo Ocean Race 2018 - MinnsDeltares
Presentation by Tony Minns, Deltares, The Netherlands, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
This presentation shows the main software used for numerically simulate the flood movement. first, it presents the HEC-RAS, then it discusses the Surface-water Modeling System (SMS), its interface, main components, DATA REQUIREMENTS and main steps to build a model using SMS.
DSD-INT 2018 Delft3D FM - validation of hydrodynamics (2D,3D) - De GoedeDeltares
Presentation by Erik de Goede, Deltares, The Netherlands, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
Stream Gauging: Necessity; Selection of gauging sites; Methods of discharge measurement; Area-Velocity method; Venturi flume; Chemical method; weir method; Measurement of velocity; Floats Surface float, Sub–surface float or Double float, Twin float, Velocity rod or Rod float; Pitot tube; Current meter; Working of current meter; rating of current meter; Measurement of area of flow; Measurement of width - Pivot point method; Measurement of depth Sounding rod, Echo- sounder.
DSD-INT 2018 Long-term streamflow forecasting for waterway transport in Centr...Deltares
Presentation by Bastian Klein (Federal Institute of Hydrology BfG) at the Delft-FEWS International User Days 2018, during the Delft Software Days - Edition 2018. 7 & 8 November 2018, Delft.
Ballast Calculation Techniques using Extrapolationsabaribmt
Duty Officer used sounding table correction in determining ballast water volume, when the Draft Survey are carried out on bulk carrier vessel. In case of over trimmed vessel, the officer couldn’t determine accurate ballast calculations. This research aimed to verify if the sounding table extrapolation is the alternative to calculate ballast tank capacity. Data on sounding table belong to their variables such as trim and volume, then it converted into a general equation. The reading of the range data and matrix calculations on sounding table data using SCILAB 6.0.2 to generate coefficients. The Mean Absolute Error (MAE) conducted the error obtained by models of equation. The result of this research showed that (1) The sounding table data can be determined as equations (2) Trims over the table and coefficients which are converted into the equation produce new volumes (3) The error of the midpoint extrapolation showed 0, then it can be used to calculate the ballast water volume
At Ampelmann, our motto is “Offshore access as easy as crossing the street”. We take this very seriously: on a day to day basis hundreds, sometimes thousands of people go to work safely using our systems all across the world. They leave their vessel, wait for the green light and transfer to their workplace, be it an offshore rig, a turbine or an FPSO. We want that experience to be equivalent to crossing the street: be aware of the action you are taking, follow the procedures and complete the transfer easy, safe and fast.
Quick tutorial of how to conduct a bridge scour computation within HECRAS. Characteristics of stream stability fundamentals are also discussed. Abutment, pier, and contraction methodologies from HEC 18 are summarized. Tips to avoid common mistakes are provided. Helpful data sources to assist design are suggested.
DSD-INT 2018 From global to local: Volvo Ocean Race 2018 - MinnsDeltares
Presentation by Tony Minns, Deltares, The Netherlands, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
This presentation shows the main software used for numerically simulate the flood movement. first, it presents the HEC-RAS, then it discusses the Surface-water Modeling System (SMS), its interface, main components, DATA REQUIREMENTS and main steps to build a model using SMS.
DSD-INT 2018 Delft3D FM - validation of hydrodynamics (2D,3D) - De GoedeDeltares
Presentation by Erik de Goede, Deltares, The Netherlands, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
Stream Gauging: Necessity; Selection of gauging sites; Methods of discharge measurement; Area-Velocity method; Venturi flume; Chemical method; weir method; Measurement of velocity; Floats Surface float, Sub–surface float or Double float, Twin float, Velocity rod or Rod float; Pitot tube; Current meter; Working of current meter; rating of current meter; Measurement of area of flow; Measurement of width - Pivot point method; Measurement of depth Sounding rod, Echo- sounder.
DSD-INT 2018 Long-term streamflow forecasting for waterway transport in Centr...Deltares
Presentation by Bastian Klein (Federal Institute of Hydrology BfG) at the Delft-FEWS International User Days 2018, during the Delft Software Days - Edition 2018. 7 & 8 November 2018, Delft.
Ballast Calculation Techniques using Extrapolationsabaribmt
Duty Officer used sounding table correction in determining ballast water volume, when the Draft Survey are carried out on bulk carrier vessel. In case of over trimmed vessel, the officer couldn’t determine accurate ballast calculations. This research aimed to verify if the sounding table extrapolation is the alternative to calculate ballast tank capacity. Data on sounding table belong to their variables such as trim and volume, then it converted into a general equation. The reading of the range data and matrix calculations on sounding table data using SCILAB 6.0.2 to generate coefficients. The Mean Absolute Error (MAE) conducted the error obtained by models of equation. The result of this research showed that (1) The sounding table data can be determined as equations (2) Trims over the table and coefficients which are converted into the equation produce new volumes (3) The error of the midpoint extrapolation showed 0, then it can be used to calculate the ballast water volume
At Ampelmann, our motto is “Offshore access as easy as crossing the street”. We take this very seriously: on a day to day basis hundreds, sometimes thousands of people go to work safely using our systems all across the world. They leave their vessel, wait for the green light and transfer to their workplace, be it an offshore rig, a turbine or an FPSO. We want that experience to be equivalent to crossing the street: be aware of the action you are taking, follow the procedures and complete the transfer easy, safe and fast.
Here is a prelim presentation I will make at the SMM Coatings Conference in Hamburg, Sept. 2010. Contact me for the .ppt after the conference. Sorry but many of the fonts converted automatically as a part of the upload process.
OFFSHORE WIND RESOURCE ASSESSMENT OFF THE SOUTH AFRICAN COASTLINEIAEME Publication
The world is undergoing a paradigm shift as more people are becoming aware of energy consumption patterns, reinforcing the need for developing cleaner and more sustainable ways to generate electrical energy. Globally, the development of onshore wind farms is sometimes impeded by factors such as aesthetic impact, acceptance by the public, the threats to surrounding biodiversity, noise from the power plant and possible land use conflicts. Due to these concerns, offshore wind plants have been developed. Offshore wind energy is generally greater in comparison to that of onshore wind energy because the wind speeds offshore are generally higher and more constant with fewer obstructions to the wind resource. The offshore wind potential for South African coastal regions was investigated and analysed in this study. Various factors such as shipping routes, oil and gas exploration fields and possible transmission connection points were taken into consideration before selecting four data collection sites. The predominant wind direction, mean wind speed, wind shear and spatial geographic information was analysed for each site. The sites’ wind direction did not have any similarities, with each site having its own prevailing wind directions. Within the 50 m hub height, Site 2 showed the best potential based on the power density. Site 1 and Site 3 showed similar power densities to each other with Site 4 showing the lowest power density. The distance to shore ranged from 200 km to 500 km with a steep continental shelf drop to a depth of approximately 3 000 m. The study conducted shows that there is offshore wind potential off the coast of South Africa. Energy generated by this method could assist South Africa to increase access to energy, reduce expensive transmission line losses to coastal provinces, and assist the country to transition towards a more sustainable future energy mix in line with developed nations.
Pre-Feasibility Study of a 1000 MW Pumped Storage Plant in Saudi ArabiaSNC-Lavalin
This paper presents the results of a prefeasibility study of a pumped storage plant which includes: impact on meeting the peak demand, site selection criteria, integration to the existing network and pumped storage plant configuration.
1. 4th
International Conference on Ocean Energy, 17 October, Dublin
1
Weather windows analysis incorporating wave height, wave
period, wind speed and tidal current with relevance to
deployment and maintenance of marine renewables
M. O’Connor1
, D. Bourke, T. Curtin, T. Lewis and G. Dalton
1
Hydraulics and Maritime Research Centre,
University College Cork,
Pouladuff Road, Togher, Cork, Ireland
E-mail: Michael.oconnor@ucc.ie
Abstract
This paper presents the results of a weather
windows analysis in order to quantify the levels of
access to marine renewables for installation and
operations & maintenance (O&M) activities.
The weather windows analysis was conducted at
three sites. The Egmond aan Zee windfarm (OWEZ)
off the Dutch North Sea coast, the Atlantic Marine
Energy Test Site (AMETS) Belmullet on the Irish
Atlantic coast and M2 in the Irish Sea.
This paper builds on previous work which
quantified weather windows by considering the
significant wave height. This paper assesses weather
windows by looking at a greater range of met-ocean
parameters in addition to significant wave height,
namely peak wave period (Tp), mean wind speed
and tidal current speed as well as applying these
parameters over a greater range of marine
renewable locations. Met-ocean data from 2008 was
used in the analysis.
Keywords: Access, Deployment, Installation, Operations &
Maintenance
1 Introduction
This paper presents the results of a weather windows
analysis of wave data from three marine renewable
locations.The Egmond aan Zee windfarm (OWEZ) off
the Dutch North Sea coast, the Atlantic Marine Energy
Test Site (AMETS) at Belmullet on the Irish Atlantic
coast and at M2 in the Irish Sea. The analysis is carried
out in order to quantify the levels of access for the
installation and operation of marine renewables which
may be deployed. Once marine renewable devices, such
as offshore wind turbines or wave energy converters
(WEC) have been deployed at sea, maintaining them
will not be as simple as for maintaining similar devices
onshore. There are many factors in an offshore
environment that make installing and operating devices
more difficult, costly and time consuming. The main
factor is that of access. In order to deploy and operate
marine renewable devices, a weather window will be
required. This will involve a period of access where the
met-ocean parameters must remain below a certain
level, long enough for the required operations to be
conducted safely. This paper will inspect the following
met-ocean parameters, significant wave height, peak
wave period, wind speed and tidal current speed. Due to
data limitations at the locations chosen, only the year of
2008 is analysed in this paper.
The Weather Windows module of the Techno-
Economic model NAVITAS1
was used for the analysis.
Levels of access at each of the three sites were
quantified based on the following four scenarios
The significant wave height (Hs) only
A Jack Up vessel with access limits based on
wave height, wind speed and tidal current.
A crew transfer Catamaran with access limits
based on wave height and tidal current.
And a Workboat with access limits based on
both the wave height and peak period.
The results of the levels of access are presented by
showing the following:
1. A comparison of the met-ocean conditions at
each site by showing the annual occurrence
frequency of each parameter at each location.
2. Persistence tables and graphs which show the
percentage access during the year for different
window lengths.
3. The seasonality of the access levels by
showing the number of hours each month that
the met-ocean conditions are below each set of
access limits.
4. The waiting periods between windows, by
showing the longest waiting period, or worst
1
Developed in HMRC under the Charles Parsons Initiative
and the Enterprise Ireland Commercialisation fund.
