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<p>Hello,</p>
<p> </p>
<p>Unfortunately, historical wind speeds on TMY files that come from NOAA data are from peak 5 minute gusts, which can have little correlation to average hourly wind speeds. At some stations integrating sensors have been added, but it will take time to push
these data through the average year data base.</p>
<p> </p>
<p>In addition, previous work in England using ultrasonic sensors has shown that NOAA data also suffers from severe drop out at speeds less than 5 to 10 MPH, which means that most sites show "0" wind speed, whereas there is actually some wind, but not enough
to move the cups on the anemometer. This can be a problem for simulation of natural ventilation.</p>
<p> </p>
<p>ASHRAE's TC 4.2 continues to discussed these and other issues, which can be viewed on ASHRAE web page in their meeting minutes.</p>
<p> </p>
<p>Jeff</p>
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<p> </p>
<div><font color="#0000ff" size="2" face="Tahoma">8=! 8=) :=) 8=) ;=) 8=) 8=( 8=) 8=() 8=) 8=| 8=) :=') 8=)8=?<br>
<br>
Jeff S. Haberl, Ph.D.,P.E., FASHRAE..............jhaberl@tamu.edu<br>
<br>
Professor............................................................Office Ph: 979-845-6507<br>
<br>
Department of Architecture.............................Lab Ph:979-845-6065<br>
<br>
Energy Systems Laboratory.............................FAX: 979-862-2457<br>
<br>
Texas A&M University.....................................77843-3581<br>
<br>
College Station, Texas, USA, 77843..................URL:www.esl.tamu.edu<br>
<br>
8=/ 8=) :=) 8=) ;=) 8=) 8=() 8=) :=) 8=) 8=! 8=) 8=? 8=)8=0<br>
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<div style="DIRECTION: ltr" id="divRpF996061"><font color="#000000" size="2" face="Tahoma"><b>From:</b> bldg-sim-bounces@lists.onebuilding.org [bldg-sim-bounces@lists.onebuilding.org] on behalf of Paul Carey [paul@zed-uk.com]<br>
<b>Sent:</b> Saturday, June 11, 2011 4:16 PM<br>
<b>To:</b> leen peeters; bldg-sim@lists.onebuilding.org<br>
<b>Subject:</b> Re: [Bldg-sim] wind speed in TMY<br>
</font><br>
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<div>Dear Leen<br>
<br>
Most weather data quotes the reference wind speed which is that at 10m above the ground as measured at certain weather stations. Adjustment factors are then made for levels of surface roughness, I.e. urban, rural environments. I think the TMY follows the same
convention.<br>
<br>
Paul<br>
<br>
<br>
Sent from my HTC<br>
<br>
Dr Paul Carey<br>
Director<br>
<br>
Zero Energy Design Ltd<br>
10a Portland Place<br>
2-22 Mottram Road<br>
Stalybridge<br>
Cheshire<br>
UK<br>
SK15 3AD<br>
<br>
Tel - +44 161 3386200<br>
Mob - +44 789 4098012<br>
Email - paul@zed-uk.com<br>
<br>
<br>
<br>
----- Reply message -----<br>
From: "leen peeters" <l.f.r.peeters@gmail.com><br>
Date: Sat, Jun 11, 2011 20:34<br>
Subject: [Bldg-sim] wind speed in TMY<br>
To: <bldg-sim@lists.onebuilding.org><br>
<br>
Hi,<br>
<br>
can anyone tell me what wind speed is exactly meant in the TMY. Is it the<br>
free, undisturbed wind speed, the wind speed above the roof, the wind speed<br>
at 10 metres above the ground ....<br>
<br>
Thanks,<br>
<br>
Leen<br>
<br>
<br>
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