Validation of a Quasi-Steady Wind Farm Flow Model in the Context of Distributed Control of the Wind Farm

Total Page:16

File Type:pdf, Size:1020Kb

Validation of a Quasi-Steady Wind Farm Flow Model in the Context of Distributed Control of the Wind Farm Validation of a quasi-steady wind farm flow model in the context of distributed control of the wind farm A.J. Brand J.W. Wagenaar Presented at: Torque 2010, 28-30 June 2010, Crete, Greece ECN-M--10-058 JULY 2010 2 ECN-M-10-058 Validation of a quasi-steady wind farm flow model in the context of distributed control of the wind farm A J Brand J W Wagenaar ECN Wind Energy ECN Wind Energy P.O. Box 1, NL 1755 ZG Petten, P.O. Box 1, NL 1755 ZG Petten, Netherlands Netherlands [email protected] [email protected] wind farm flow model, and presents load Abstract quantifiers calculated by the model. First, the research objectives of the FP7 project This work presents validation of an Aeolus are described (section 2) and the intermediate version of a quasi-steady quasi-steady wind farm flow model is wind farm flow model which will be part of introduced (section 3). Next, a comparison distributed control of a wind farm. In is presented between model output for and addition power and three load quantifiers measured data from the ECN Wind turbine as calculated by the model are Test site Wieringermeer EWTW (section demonstrated. It is concluded that 4). In addition power and three short-term differences between measurement and load quantifiers as calculated for the prediction are smaller than 2 m/s (wind considered cases are presented (section speed) and 200 kW (power), measured 5). Finally, a summary of the work and an minimum in wind speed and aerodynamic outlook to future work are given (section power at second or third turbine is not 6). predicted, and main differences originate from un-modelled spatial variations in wind speed and too gradually modelled decay 2. Objectives and approach of wind speed. The general objectives of the FP7 project Keywords: Model predictive control, Aeolus are to develop models that allow Wind farms, Offshore wind energy real-time predictions of flow in a wind farm and incorporate data from a network of 1. Introduction sensors, and to develop control paradigms that acknowledge the uncertainty in the In Europe wind farms are being developed modelling and dynamically manage the at a large scale. These installations are flow resource in order to optimize specific expected to operate similar to control objectives. conventional power plants and to provide Specific objectives of the project, quality power at the lowest possible cost. contained in the two flow modelling work During operation this is achieved by packages, include the development of a addressing three control objectives at wind quasi-steady and a dynamic flow model. farm level: maximum power production, The quasi-steady flow model relates single minimum structural loads and optimal turbine production and loading to a map of integration into the power system. wind speeds [4, 5, 6], in contrast to the The EU project FP7-ICT STREP dynamic flow model which describes 22548 / Aeolus is aimed at the deviations from the steady model due to development of distributed control of large rapidly changing flow effects [7]. offshore wind farms [1, 2]. In this context a quasi-steady wind farm flow model is The quasi-steady flow model is derived developed, which is to be part of the from fluid dynamics principles and is supervisory control algorithm [3]. based on a database of meteorological This paper addresses validation of an and wind turbine related measurements. It intermediate version of the quasi-steady is developed in two stages: first a preliminary version (finished April 2009 theory the aerodynamic state of a wind and reported separately [4, 5, 6]) and next turbine is expressed in terms of an axial the final version (finished February 2010, induction factor. Relations for the mean also reported separately [8, 9] and partly and the standard deviation of the axial covered in this paper). induction factor both bring the effect of In fact the quasi-steady flow model is turbulence into account. Subsequently a model of the control object "wind farm"; aerodynamic power, tower bending where "model" means a mathematical moment, blade bending moment and rotor map/function in the form of equations (or shaft torque are calculated. In addition initially look-up tables) which relates farm velocity deficit and extra turbulence due to output (power and load quantifiers) to the single wind turbine are calculated. measured quantities (e.g. rotor speed, The model treats a cluster of wind blade pitch angle, wind speed), references turbines by linking individual wind turbines (e.g. power set point) and disturbances via their wakes. For the given wind (unmodelled system inputs). Figure 1 direction, for all wind turbines in the cluster shows the basic structure. The model is the streamwise and the spanwise distance steady in the sense that it is valid over downstream each wind turbine is averaging periods of 10 minutes, in determined. Subsequently, this infomation contrast to the dynamic flow model which is employed in order to calculate all local is dynamic in the sense that it describes values of velocity deficit and added deviations from the mean. The model is turbulence by using decay laws. quasi steady because it gives mean as 3.2 Load quantifiers well as standard deviation of a quantity, and by doing so provides information on The quasi-steady wind farm flow model variations which are translated into load translates wind speed mean values and quantifiers. standard deviations into mean values and standard deviations of mechanical loads. 3. Quasi steady wind farm Subsequently the model translates this information into load quantifiers. In this flow model section the approach is presented. 3.1 Flow model First, as described in preceding The quasi-steady wind farm flow model publications [4, 8], it is assumed that load allows the wind farm controller to calculate mean μL as well as load standard deviation in real time maps of wind, loads and σL depend on wind speed mean μU and energy, or to be more specific, wind speed wind speed standard deviation σU: at each turbine in a wind farm plus tower bending moment, blade bending moment, , and , . rotor shaft torque and aerodynamic power L L U U L L U U of each turbine as a function of "ambient" This crucial assumption is motivated by wind speed, wind direction and turbulence experimental and modelling based intensity. The corresponding flow chart is identification of the parameters that shown in figure 2. influence equivalent loads [14, part 1, sub B, section 5.4]. The conclusions in the The structure and the details of the flow referred work are that: model, which are described in preceding publications [5, 6], are summarized in this The primary fatigue load parameter is the standard deviation of the longitudal section. 1 Apart from sub-models based on wind speed component , and classic momentum theory [10], inspired by The equivalent load is a function of the the literature on wind turbine wakes [11, wind speed standard deviation σU and, 12, 13, 14 part 1 sub A section 2.4, 15, because at higher wind speeds a 16], this model includes specially constant value of the turbulence developed sub-models for creation and intensity may be assumed, the mean decay of velocity deficit, creation and wind speed μU. decay of added turbulence, impact of turbulence on average values, and standard deviation of all quantities. The model treats individual wind 1 The second important parameter is yaw turbines separately. By using momentum misalignment, and the third important parameter is turbulence structure Secondly, it is assumed that loads are normally distributed. This assumption is Section 5 demonstrates the equivalent fair in a short-term assessment of wind load concept on basis of measured data. turbine components because: Future work is aimed at relating equivalent In a short time period (10 minutes) the load to fatigue load. number of observations or revolutions is high (600 resp. ~200), and 4. Model output versus Under normal operation during a 10- minute period wind turbine loads have measured data comparison experimentally been found to vary with 4.1 Overview well-defined mean and standard deviation. In this section output from an intermediate version of the quasi-steady flow model is The load quantifier selected is the compared to measured data from the ECN Wind turbine Test site Wieringermeer equivalent load Leq [e.g. 17, page 80] of a EWTW. (The EWTW consists of a row of series of loads Lj (j = 1, 2, 3, …, N): five 2.5 MW wind turbines plus a meteo 1 1 mast.) Various wind speed and direction m m m cases are presented and discussed, see Leq niLi L j N i N j figure 3 for a definition sketch, and = m-th raw moment of the observed loads. modelling issues are identified in the light of the modelling objective. Here L indicates the load, m is the slope of the SN-curve of the material and N is the 4.2 Inflow perpendicular to turbine row number of load observations in the time In this section inflow perpendicular to the period. Furthermore ni is the number of row of turbines (wd2) together with four loads with value Li, whereas j indicates an wind speed cases is considered. This wind individual load in the series Lj. direction case is relevant because it shows to what extent the state of each turbine is If the load is a moment (e.g. tower bending predicted if all turbines have the same moment, or blade bending moment), ni is inflow. The wind speed cases are relevant the number of load observations of level Li because they correspond to near cut-in in the time period and N = Σi ni is the (ws1), halfway nominal power (ws2), near number of load observations in that period nominal power (ws3) and constant power [e.g.
Recommended publications
  • Island Hopping in the Aeolians Tamara Thiessen 4 Minutes Reading Time
    ISLAND HOPPING IN THE AEOLIANS TAMARA THIESSEN 4 MINUTES READING TIME THE LUMPY, CRINKLE­CUT ISLES OF PUMICE GREY STONE ARE ERUPTED PROTRUSIONS OF UNDERWATER VOLCANOES Tamara Thiessen takes a whirlwind tour of the picturesque archipelago off the shores of Sicily “The sea is in my veins – all my family have worked in boating and fishing. It’s a very special relationship, which all the Aeolians have with the sea … You have to live with its moods and our survival depends on it – particularly in winter, when sometimes we can’t come and go.” Silvia Carbone is the owner of a small art­filled hotel on the island of Lipari. It is very marine in decor, with its azzurro­coloured tiles and inner courtyard billowing with sail­like curtains. This is our homely bolthole in the little harbour of Canneto – our first port of call in the Aeolians. Like all islands, getting there takes some mental gymnastics. In the case of the Aeolians – an archipelago of seven islands off Sicily’s north coast – the workout becomes even more vigorous as you try to decide which islands you should visit– in what order – and how to get between them. Though their lyrical string of names – Lipari, Panarea, Vulcano, Stromboli, Salina, Alicudi and Filicudi – would have you believe it is as easy as tiptoeing through the tulips – boat travel always means seasonal precariousness. We get an immediate taste of that, coming in October – just when the transport switches to its low­season schedule and the waters get choppier. Being an islander myself (from Tasmania, in Australia) – islands are ever­present in my imagination – and the prospect of holing myself up on these breakaway pieces of land is as tempting as their wild, UNESCO­listed nature and deep blue myth­laden seas.
    [Show full text]
  • Myths and Legends: Odysseus and His Odyssey, the Short Version by Caroline H
    Myths and Legends: Odysseus and his odyssey, the short version By Caroline H. Harding and Samuel B. Harding, adapted by Newsela staff on 01.10.17 Word Count 1,415 Level 1030L Escaping from the island of the Cyclopes — one-eyed, ill-tempered giants — the hero Odysseus calls back to the shore, taunting the Cyclops Polyphemus, who heaves a boulder at the ship. Painting by Arnold Böcklin in 1896. SECOND: A drawing of a cyclops, courtesy of CSA Images/B&W Engrave Ink Collection and Getty Images. Greek mythology began thousands of years ago because there was a need to explain natural events, disasters, and events in history. Myths were created about gods and goddesses who had supernatural powers, human feelings and looked human. These ideas were passed down in beliefs and stories. The following stories are about Odysseus, the son of the king of the Greek island of Ithaca and a hero, who was described to be as wise as Zeus, king of the gods. For 10 years, the Greek army battled the Trojans in the walled city of Troy, but could not get over, under or through the walls that protected it. Finally, Odysseus came up with the idea of a large hollow, wooden horse, that would be filled with Greek soldiers. The people of Troy woke one morning and found that no army surrounded the city, so they thought the enemy had returned to their ships and were finally sailing back to Greece. A great horse had been left This article is available at 5 reading levels at https://newsela.com.
    [Show full text]
  • Epic Anger, and the State of the (Roman) Soul in Virgil's First Simile1
    Epic Anger, and the State of the (Roman) Soul in Virgil’s First Simile1 Kirk Freudenburg Yale University Virgil’s Aeneid begins with the goddess, Juno, both ‘still’ and ‘already’ angry: mene incepto desistere victam? ‘Am I to desist from what I’ve begun, beaten?’ Rivers of Trojan blood have been spilt, and Priam’s city has been looted and leveled. Extreme revenge has been exacted in the form of retaliatory rapes, forced enslavements, and so on. And yet somehow Juno thinks that her project of paying back the Trojans is not only not f nished, but only just begun. T e famous, translinguistic pun that issues from her f rst words (mene incepto) reminds us of Achilles’ rage, certainly, but by the Iliad’s end Achilles has gained some 1 T is paper is a heuristic ‘f rst go’ at an idea that I have been mulling over for years, on the problem of anger in ancient epic, and the soul work of Virgil’s f rst simile. Since I plan to do a larger workup of these ideas for a (distantly) forthcoming book, I will be more than happy to receive feedback on the paper’s contents and arguments. T e paper’s core ideas were tested at the annual Latin Day Colloquium held at Yale University on April 16, 2016. For helpful com- ments and criticisms, I wish to thank the day’s star and colloquium leader, Denis Feeney, as well as the event’s invited speakers, Jay Reed, Tom Biggs, and Irene Peirano. T anks also to Christina Kraus for organizing the event, and to the group of graduate respondents who were active participants throughout the day: Niek Janssen, Rachel Love, Kyle Conrau-Lewis, and Treasa Bell.
    [Show full text]
  • Meet the Philosophers of Ancient Greece
    Meet the Philosophers of Ancient Greece Everything You Always Wanted to Know About Ancient Greek Philosophy but didn’t Know Who to Ask Edited by Patricia F. O’Grady MEET THE PHILOSOPHERS OF ANCIENT GREECE Dedicated to the memory of Panagiotis, a humble man, who found pleasure when reading about the philosophers of Ancient Greece Meet the Philosophers of Ancient Greece Everything you always wanted to know about Ancient Greek philosophy but didn’t know who to ask Edited by PATRICIA F. O’GRADY Flinders University of South Australia © Patricia F. O’Grady 2005 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without the prior permission of the publisher. Patricia F. O’Grady has asserted her right under the Copyright, Designs and Patents Act, 1988, to be identi.ed as the editor of this work. Published by Ashgate Publishing Limited Ashgate Publishing Company Wey Court East Suite 420 Union Road 101 Cherry Street Farnham Burlington Surrey, GU9 7PT VT 05401-4405 England USA Ashgate website: http://www.ashgate.com British Library Cataloguing in Publication Data Meet the philosophers of ancient Greece: everything you always wanted to know about ancient Greek philosophy but didn’t know who to ask 1. Philosophy, Ancient 2. Philosophers – Greece 3. Greece – Intellectual life – To 146 B.C. I. O’Grady, Patricia F. 180 Library of Congress Cataloging-in-Publication Data Meet the philosophers of ancient Greece: everything you always wanted to know about ancient Greek philosophy but didn’t know who to ask / Patricia F.
    [Show full text]
  • HTS Aeolian Islands
    SOUTHERN ITALY - MEDITERRANEAN SEA DISCOVER THE ARCHIPELAGO OF THE AEOLIAN ISLANDS - A unique UNESCO World Heritage Site BRIGANTINE FLORETTE Historical Tallship Sailing LTD Mediterranean Sea Southern Italy - Aeolian Archipelago Set Sail with the wooden Tallship Florette the last of her kind and sail in her home waters to explore the unique archipelago of the Unesco-protected Aeolian Islands. The seven islands, including Lipari, Vulcano, Salina, Panarea, Stromboli, are a little piece of paradise, a magical outdoor playground. Our guests from all walks of life looking for adventure and that something different. Take a Vespa island tour on Lipari, experience the charm of Panarea and hike the nature reserve of Salina. Enjoy the creative "Cucina Eoliana" and explore the 6000-year-old culture of these islands. Swim and snorkel in secluded bays with crystal clear water and dark beaches made of fine, black lava sand. Marvel at the most active volcano in Europe. Explore Stromboli on an adventurous night hike. Climb Vulcano slumbering in the sulfur steam and then enjoy a healing bath in the sulfur mud. DISCOVER THE MEDITERRANEAN SEA: SOUTHERN ITALY - CALABRIA-AEOLIAN ISLANDS ARCHIPELAGO A unique UNESCO World Heritage Site You can expect sailing fun, hiking on active volcanoes, breathtaking nature, culture & adventure and all that with the right breeze from Italy's Dolce Vita. Travel dates are weekly from May 8th, 2021 - October 23rd, 2021 from 849.- Euro Included in the voyage price: • 7 days sailing trip on the historical windjammer as an active sailor • Half board with breakfast and six delicious meals • Diesel costs & tender services land - ship • Snorkelling gear, kayaks and SUPs are available onboard • Safety briefing with a basic knot & sailing school • Professional crew with the Haynes family guarantee an unforgettable experience Not included in the voyage price: • Arrival and departure transfers, shore excursions, drinks, visas and personal insurance.
    [Show full text]
  • What Is Greek About Greek Mythology?
    Kernos Revue internationale et pluridisciplinaire de religion grecque antique 4 | 1991 Varia What is Greek about Greek Mythology? David Konstan Electronic version URL: http://journals.openedition.org/kernos/280 DOI: 10.4000/kernos.280 ISSN: 2034-7871 Publisher Centre international d'étude de la religion grecque antique Printed version Date of publication: 1 January 1991 Number of pages: 11-30 ISSN: 0776-3824 Electronic reference David Konstan, « What is Greek about Greek Mythology? », Kernos [Online], 4 | 1991, Online since 11 March 2011, connection on 01 May 2019. URL : http://journals.openedition.org/kernos/280 ; DOI : 10.4000/kernos.280 Kernos Kernos, 4 (1991), p. 11-30. WHAT IS GREEK ABOUT GREEK MYTHOLOGY? The paper that follows began as a lecture, in which 1 attempted to set out for a group of college teachers what was specifie to Greek mythology, as opposed to the mythologies of other peoples1. Of course, there is no single trait that is unique to Greek myths. But there are several characteristics of Greek mythology that are, despite the intense attention it has received for decades and even centuries, still not commonly noticed in the scholarly literature, and which, taken together, contribute to its particular nature. By the device of contrasting with Greek myths a single narrative from a very different society, 1 thought that 1 might set in relief certain features that have by and large been overlooked, in part precisely because they are so familiar as to seem perfectly natural. My survey of the characteristics of Greek mythology, needless to say, makes no pretense to being exhaustive.
    [Show full text]
  • Greek Gods/Mythology Notes - Information on the Greek Belief System Comes from Many Sources
    Greek Gods/Mythology Notes - Information on the Greek belief system comes from many sources. Unlike followers of religions such as Christianity, Judaism, & Islam, the Greeks did not have a single sacred text, such as the Bible or Koran from which their beliefs and religious practices derived. Instead, they generally used oral traditions, passed on by word of mouth, to relate sacred stories. Priest and priestesses to various gods would also guide people in worship in various temples across Greece. We know something about these beliefs because Greek poets such as Homer, Hesiod and Pindar, and Greek dramatists such as Euripides, Aristophanes & Sophocles mention the myths in their various works. Greek mythology, however, was not static- it was constantly changing and evolving. Thus, there are often many different versions (and some that are contradictory toward one another) of the various Greek myths. Thus, some of the example myths you read in here may differ from ones you have previously heard. It does not necessarily make either version “wrong”- simply different. - The Greeks had many Gods & Goddesses- over three thousand if one were to count the many minor gods and goddesses. These deities made up the Greek pantheon, a word used to mean all the gods and goddesses (from the Greek word “pan” meaning all, and “theos” meaning gods). However, throughout Greece, there were always twelve (called the Twelve Olympians) that were the most important. They are: 1. Zeus 2. Hera 3. Poseidon 4. Athena 5. Apollo 6. Artemis 7. Hephaestus 8. Ares 9. Hermes 10. Aphrodite 11. Demeter 12. Dionysus 13.
    [Show full text]
  • Mythology, Greek, Roman Allusions
    Advanced Placement Tool Box Mythological Allusions –Classical (Greek), Roman, Norse – a short reference • Achilles –the greatest warrior on the Greek side in the Trojan war whose mother tried to make immortal when as an infant she bathed him in magical river, but the heel by which she held him remained vulnerable. • Adonis –an extremely beautiful boy who was loved by Aphrodite, the goddess of love. By extension, an “Adonis” is any handsome young man. • Aeneas –a famous warrior, a leader in the Trojan War on the Trojan side; hero of the Aeneid by Virgil. Because he carried his elderly father out of the ruined city of Troy on his back, Aeneas represents filial devotion and duty. The doomed love of Aeneas and Dido has been a source for artistic creation since ancient times. • Aeolus –god of the winds, ruler of a floating island, who extends hospitality to Odysseus on his long trip home • Agamemnon –The king who led the Greeks against Troy. To gain favorable wind for the Greek sailing fleet to Troy, he sacrificed his daughter Iphigenia to the goddess Artemis, and so came under a curse. After he returned home victorious, he was murdered by his wife Clytemnestra, and her lover, Aegisthus. • Ajax –a Greek warrior in the Trojan War who is described as being of colossal stature, second only to Achilles in courage and strength. He was however slow witted and excessively proud. • Amazons –a nation of warrior women. The Amazons burned off their right breasts so that they could use a bow and arrow more efficiently in war.
    [Show full text]
  • Stevenson at Vulcano in the Late 19Th Century: a Scottish Mining Venture in Southern Europe
    Proc Soc Antiq Scot 147 (2017), 303–323 A SCOTTISH MINING VENTURE IN SOUTHERN EUROPE | 303 DOI: https://doi.org/10.9750/PSAS.147.1255 Stevenson at Vulcano in the late 19th century: a Scottish mining venture in southern Europe E Photos-Jones1, 2, B Barrett2 and G Christidis3 ABSTRACT This project seeks to recover and record the archaeological evidence associated with the extraction of sulfur (and perhaps other minerals as well) by James Stevenson, a Glasgow industrialist, from the volcanic island of Vulcano, Aeolian Islands, Italy, in the second half of the 19th century. This short preliminary report sets the scene by linking archival material with present conditions and by carrying out select mineralogical analyses of the type of the mineral resource Stevenson may have explored. New 3D digital recording tools (Structure-from-Motion photogrammetry) have been introduced to aid future multidisciplinary research. This is a long-term project which aims to examine a 19th-century Scottish mining venture in a southern European context and its legacy on the communities involved. It also aims to view Stevenson’s activities in a diachronic framework, namely as an integral part of a tradition of minerals exploration in southern Italy from the Roman period or earlier. INTRODUCTION causing considerable damage and halting works. Stevenson died in 1903 and his landholdings and James ‘Croesus’ Stevenson (1822–1903) (Illus mineral rights were sold to the Conti family of 1) was a Glasgow industrialist manufacturing Lipari (Campostrini et al 2011: 21). sodium and potassium chromates for the dyeing Stevenson was an astute businessman, a and calico industries (Stevenson 2009: 162).
    [Show full text]
  • Aeolus Scientific Calibration and Validation Implementation Plan
    estec European Space Research and Technology Centre Keplerlaan 1 2201 AZ Noordwijk The Netherlands T +31 (0)71 565 6565 F +31 (0)71 565 6040 www.esa.int Aeolus Scientific Calibration and Validation Implementation Plan Prepared by A. G. Straume, D. Schuettemeyer, J. von Bismarck, T. Kanitz, T. Fehr Reference EOP-SM/2945/AGS-ags Issue 1 Revision 2 Date of Issue 15-Nov-2019 Status Issued Document Type PL - Plan Distribution Public Title ASCV IP Issue 1 Revision 2 Authors A.G. Straume, D. Schuettemeyer, J. Date 15-Nov-2019 von Bismarck, T. Kanitz, T. Fehr Approved by Date T. Parrinello (EOP-GM) 29 November 2019 Reason for change Issue Revision Date First draft by. D. Schuettemeyer including: overall 0 1 February 2015 structure based on S-3 CAL/VAL Implementation Plan, inclusion of Aeolus CAL/VAL Requirements doc content, overview of Aeolus CAL/VAL proposals Second draft, editorial updates based on review by 0 2 October 2015 AGS, TK, JvB Third draft, revisions by A.G Straume of document 0 3 January 2016 structure replacing calval requirements text with calval requirements table and mapping to proposals, geographical coverage, various updates. Fourth draft, inclusion of revisions by J. von Bismarck, 0 4 February 2016 T. Kanitz, D. Schuettemeyer First issue 1 0 February 2018 Update following review R. Koopman 1 1 September 2018 Update including proposals following CAL/VAL AO 1 2 November 2019 call reopening February 2018 Issue 1 Revision 2 Reason for change Date Pages Paragraph(s) Update including proposals after CAL/VAL AO 15/11/2019 all all reopening 2018 Page 2/146 Aeolus Scientific Calibration and Validation Implementation Plan Date 15-Nov-2019 Issue 1 Rev 2 Table of contents: 1 INTRODUCTION ............................................................................................................................
    [Show full text]
  • Wandering Poets and the Dissemination of Greek Tragedy in the Fifth
    Wandering Poets and the Dissemination of Greek Tragedy in the Fifth and Fourth Centuries BC Edmund Stewart Abstract This work is the first full-length study of the dissemination of Greek tragedy in the earliest period of the history of drama. In recent years, especially with the growth of reception studies, scholars have become increasingly interested in studying drama outside its fifth century Athenian performance context. As a result, it has become all the more important to establish both when and how tragedy first became popular across the Greek world. This study aims to provide detailed answers to these questions. In doing so, the thesis challenges the prevailing assumption that tragedy was, in its origins, an exclusively Athenian cultural product, and that its ‘export’ outside Attica only occurred at a later period. Instead, I argue that the dissemination of tragedy took place simultaneously with its development and growth at Athens. We will see, through an examination of both the material and literary evidence, that non-Athenian Greeks were aware of the works of Athenian tragedians from at least the first half of the fifth century. In order to explain how this came about, I suggest that tragic playwrights should be seen in the context of the ancient tradition of wandering poets, and that travel was a usual and even necessary part of a poet’s work. I consider the evidence for the travels of Athenian and non-Athenian poets, as well as actors, and examine their motives for travelling and their activities on the road. In doing so, I attempt to reconstruct, as far as possible, the circuit of festivals and patrons, on which both tragedians and other poetic professionals moved.
    [Show full text]
  • ADM-Aeolus Ocean Surface Calibration and Level-2B Wind-Retrieval Processing
    S02 - P04 - 1 ADM-Aeolus Ocean Surface Calibration and Level-2B Wind-Retrieval Processing Jos de Kloe1, Ad Stoffelen1, Gert-Jan Marseille1, David Tan2, Lars Isaksen2, Charles Desportes3, Christophe Payan3, Alain Dabas3, Dorit Huber4, Oliver Reitebuch5, Pierre Flamant6, Herbert Nett7, Olivier Le Rille7, and Anne-Grete Straume7 1Royal Dutch Meteorological Institute (KNMI), P.O. Box 201, NL 3730 AE, De Bilt, The Netherlands; email: [email protected]; 2European Center for Medium-range Weather Forecasting (ECMWF), Shinfield Park, Reading RG2 9AX, UK; 3Met´ eo´ France, 42 avenue Coriolis, 31057 Toulouse, France; 4DorIT, Munich, Germany; 5DLR, Oberpfaffenhofen, D-82234 Wessling, Germany; 6LMD/IPSL, 91128 Palaiseau, France; 7ESA/ESTEC, Postbus 299, NL 2200 AG, Noordwijk, The Netherlands. ABSTRACT atmospheric temperature and pressure profiles (from a numerical weather prediction model) to retrieve the wind Preparations for the European Space Agency’s (ESA) profile from the spectrometer data. This software will be Atmospheric Dynamics Mission (ADM-Aeolus), which is made available by ESA as source code, free of charge, scheduled for launch in 2011, are in full progress. The to all interested users in the meteorological/research direct detection high spectral resolution Doppler Wind community, and may be used as standalone software, Lidar (DWL) satellite instrument will be the first to mea- or integrated as subroutine in a larger system for use in sure wind profiles from space, from the surface up to scientific or operational applications. The working of the 30 km altitude [1] and [2]. To achieve this, a laser at L2Bp will be illustrated at the conference. 355 nm pulsed at 100 Hz is pointed towards the at- mosphere.
    [Show full text]