Wind Tunnel Specifications

1
Wind Tunnel Specifications

• 50kW synchronous AC motor, centrifugal fan
• Vertical diffuser, area ratio 2.87
• Horizontal diffuser, area ratio 2.65
• Settling chamber 2650 x 2150 x 2500mm length
• Contraction, area ratio 11.4
• Working section, 1000x500mm outlet, open sided
• Four plastic screens (open area ratio 0.65) fixed
  in the fan adaptor and diffuser sections
• Aluminium Honeycomb in the settling chamber,
  50.8mm thickness, 6.3mm cell size

2
Flow Uniformity
5 m/s
10 m/s
15 m/s

• Flow velocity contours at tunnel outlet without
  working section

3
Flow Uniformity
Velocity contours in working section
5 m/s
10 m/s

• Flow velocity is within 1 of mean velocity
  across the 1m x 0.5m working section outlet

4
Horizontal Wind Gradient

• Mean pressures A B measured simultaneously with
  two pitot-static tubes spanning 200mm at the
  anemometer cup location. Procedure repeated with
  p-s tubes reversed.
• Linear regression shows 0.3 difference in
  pressure

5
Turbulence Measurements
single normal hotwire
Pitot-static tube (design similar to AMCA type)
anemometer filter (5kHz)
Pressure Transducer Ashcroft XLdp
Analog-Digital Converter NI PCI-6013 (16 bit)
PC
6
Turbulence Intensity
Turbulence Intensity
Mean Velocity (m/s) Turbulence Intensity ()
4.01 0.19
8.07 0.30
12.20 0.44
16.16 0.38
7
Wind Tunnel Turbulence Spectra
8
Cup Anemometer Calibration Setup
9
Calibration Procedure
Pitot-static tube (design similar to AMCA type)
Pressure Transducer Ashcroft XLdp
HP Frequency Counter
Analog-Digital Converter NI PCI-6013 (16 bit)
PC

• Risoe P2546A cup anemometer calibrated using the
  Measnet procedure
• No blockage included for Newcastle result

Slope Offset Correlation coefficient
Newcastle 0.6267 0.2668 0.999989
DEWI 0.6267 0.248 0.999992