h1 high low mid 283 181 224

h2 129 147 144

h3 138 149 149

h4 144 150 150

1 2 3 4 5 6

Duct cross-sectional area (m ) 0.000490874 7.85398E-05 8.99202E-05 0.000109359 0.000151747 0.000490874

3

high high high low low low mid mid mid

Volume collected (litres) 5 5 5 5 5 5 5 5 5

Time to collect (sec) 37.6 41.0 41.2 93.3 92.9 92.1 55.6 58.9 57.5

h5 194 154 173

h6 232 167 194 1 0 2 60.4

Measured manometer readings at B to F Calculated pressure head differences (m) relative to that at A (m) h2-h1 -154 -34.0 -80.0 h3-h1 -145 -32.0 -75.0 h4-h1 -139 -31.0 -74.0 h5-h1 -89.0 -27.0 -51.0 h6-h1 -51.0 -14.0 -30.0 h2-h1 -126 -23.4 -61.2 h3-h1 -95.5 -17.7 -46.3

Volume Average Flow Velocity velocity velocity velocity collected Times rate at 1 at 2 at 3 at 4 (litres) (sec) (litres/s) (m/s) (m/s) (m/s) (m/s) 5.0 39.9 0.125 0.255 1.59 1.39 1.14 5.0 92.8 0.054 0.110 0.686 0.599 0.493 5.0 57.3 0.087 0.178 1.11 0.970 0.797

0 0.0 0.0 -20-10.0 -40 -5.0 60.4 68.3

high low mid72.8 81.2 141.4

60.4 60.4

68.3 68.3

72.8 72.8

81.2 81.2

141.4 141.4

Pressure head differences (m) Pressure head differences (m) Pressure head differences (m)

-20.0 -60 -10.0 -80 -30.0 -100 -15.0 -40.0 -120 -50.0-140 -20.0 -60.0-160 -25.0

Pressure hea Pressure head diff

-60.0 -25.0 -180 -70.0 -30.0 -80.0 Distance from A (mm)

-90.0 -35.0

Distance from A (mm)

-40.0

Distance from A (mm)

3 68.3

4 72.8

5 81.2

6 141.4

Calculated pressure head differences (m) h4-h1 -63.5 -11.8 -30.8 h5-h1 -31.4 -5.82 -15.2 h6-h1 0 0 0

Velocity Velocity at 5 at 6 (m/s) (m/s) 0.825 0.255 0.355 0.110 0.575 0.178

141.4

141.4 141.4

Series1 Series2

Series1Series2 Series1

Series2