28.02.2013 Views

Introduction to Acoustics

Introduction to Acoustics

Introduction to Acoustics

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

134 Part A Propagation of Sound<br />

Part A 4.8<br />

Table 4.2 Pasquill (meteorological) stability categories<br />

Wind speed a Daytime 1 h before sunset Nighttime<br />

(m/s) Incoming solar radiation (mW/cm 2 ) or after sunrise cloud cover (octas)<br />

> 60 30–60 < 30 Overcast 0–3 4–7 8<br />

≤ 1.5 A A–B B C D ForG b F D<br />

2.0–2.5 A–B B C C D F E D<br />

3.0–4.5 B B–C C C D E D D<br />

5.0–6.0 C C–D D D D D D D<br />

> 6.0 D D D D D D D D<br />

a measured <strong>to</strong> the nearest 0.5m/s at 11 m height<br />

b Category G is an additional category restricted <strong>to</strong> nighttime with less than 1 octa of cloud and a wind speed of less than 0.5m/s<br />

Table 4.3 CONCAWE meteorological classes for noise prediction<br />

Meteorological Pasquill stability category and wind speed (m/s)<br />

category Positive is <strong>to</strong>wards receiver<br />

A, B C, D, E F, G<br />

1 v

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!