Index of /turbdata/agard/chapter5/PCH02
AGARD Working Group Data Base - October 1997
Case PCH01
These files contain smooth and rough wall pipe mean velocity data.
The data is presented as law of the wall plots and as velocity
defect plots. The rough wall data is corrected for the effective
origin of the roughness. The effective origin of the roughness
was found by assuming the universal logarithmic law. See Perry and
Joubert J. Fluid Mech. Vol 17, 1963.
Files are named as follows
PCH02_(Smooth or rough)(defect or law of the wall).First three digits
of the Reynolds number.
Reynolds stress data for the rough wall pipe is contained in file
PCH2R.STS
Reynolds stress data for the smooth wall pipe is contained in files
PCH2Sxxx.STS where xxx is the first three digits of the Reynolds number in
thousands.
Details of the Geometry of the Experiment are as follows.
The apparatus consists of a long cylindrical pipe fitted with an upstream
axisymmetric settling chamber and 27:1 contraction. The settling chamber
consists of honeycomb flow straighteners and 4 screens.
Smooth Pipe: precision drawn brass tubing
internal Diameter = 0.099 m
Length = 41.17 m
Measuring station: L/D = 398.5
static pressure locations:
L/D = 49.2, 109.9, 170.5, 231.1, 291.7, 352.3
Smooth wall flow was tripped using a sandpaper strip, 50 grit and 15 cm long.
Rough Pipe: "k-type" roughness (0.25 mm height, 2.5 mm cell size, woven fabric wedding vale glued to the inside of the pipe)
internal Diameter = 0.101 m
Length = 41.14 m
Measuring station: L/D = 390.7
static pressure locations:
L/D = 46.1, 50.3, 176.8, 206.5, 226.5, 285.7, 345.1
Static pressure probes were used, not taps, 2.0 mm dia hypodermic tubing 20 mm off the wall.
----- NOTE added after publication !!! ----- Mar/2003 ---
The velocity profiles for the rough pipes in PCH02_RL.* are CORRECTED
to match the SMOOTH law of wall. To obtain actual values of U/U* the
following offsets have to be substracted from the whole profile
File Roughness height Velocity offset
k U*/nu DU/U*
---------------------------------------------------
PCH02_RL.075 8.26 1.602
PCH02_RL.100 11.77 3.016
PCH02_RL.125 14.44 3.748
PCH02_RL.150 17.37 4.476
PCH02_RL.175 20.42 4.944
PCH02_RL.200 23.25 5.139