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Observations of the Spatial Observations of the Spatial Structure of Turbulence with Structure of Turbulence with Horizontal Arrays of InHorizontal Arrays of In--Situ Situ
SensorsSensors
Thomas W. HorstThomas W. Horst
National Center for Atmospheric ResearchNational Center for Atmospheric ResearchBoulder, CO, USABoulder, CO, USA
Hanna and Chang (1992)
Orthogonal grid of 13, logarithmically-spaced (312m-10km), anemometers at 10m height
Lee and Black (1994)
Orthogonal grid of 11 thermocouples with a sonic anemometer at the vertex to measure scalar flux attenuation caused by spatial displacement of the scalar sensor from the anemometer
Tong, Wyngaard and Brasseur (1998)
PSU Horizontal Array Technique: Measurement of 2D spatially-filtered turbulence using 9 sonic anemometers in a crosswind array along with Taylor's hypothesis in the streamwise direction.
Observational investigation of LES sub-filter scale closure models
S
4S cos(b)
Wind
Direction
b
dt=2S sin(b)/Udt=S sin(b)/U
dt= -2S sin(b)/Udt= -S sin(b)/U
Project array onto crosswind direction
S
Wind
Direction
b
Project array onto crosswind direction
n=5
S
4S cos(b)
4S cos(b)
dt = 4S cos(b)/U
Wind
Direction
b
Use Taylor's hypothesis for streamwise averaging
S
dt = 4S cos(b)/U
Wind
Direction
b
Use Taylor's hypothesis for streamwise averaging
S
4S cos(b)
4S cos(b)
dt = 2S cos(b)/U
Wind
Direction
b
Calculate Sub-Filter-Scale Variables
S
1 2 3 4 5 6 7 8 9
Tong et al. Horizontal Array Technique
S
1 2 3 4 5 6 7 8 9
Tong et al. Horizontal Array Technique
S
1 2 3 4 5 6 7 8 9
Tong et al. Horizontal Array Technique
S
1 2 3 4 5 6 7 8 9
Tong et al. Horizontal Array Technique
S
1 2 3 4 5 6 7 8 9
Tong et al. Horizontal Array Technique
S
1 2 3 4 6 7 8 9
Tong et al. Horizontal Array Technique
5
4
S
1 2 3 5 6 7 8 9
Tong et al. Horizontal Array Technique
4
S
1 2 3 5 6 7 8 9
Tong et al. Horizontal Array Technique
4
S
1 2 3 5 6 7 8 9
Tong et al. Horizontal Array Technique
Horizontal Array Turbulence Study (HATS)
Cerutti and Meneveau (2000)
Cerutti and Meneveau applied the horizontal array technique in the wind tunnel with 4 X-probes placed transverse to the flow direction to study filtered velocity statistics in grid and wake turbulence.
Higgins et al. (2007)
16 sonics were deployed in a 4x4 planar grid to enable 3D turbulence filtering.PDF's and spectra of the stresses were found to collapse by reducing the 3D filter scale as L3D
= 0.84 L2D
.
OHATS
HATS
CHATS