Scale exponents of longitudinal and transverse structure functions in homogeneous and isotropic turbulence generated in a wind tunnel
Published 2019-02-06
Keywords
- active grid,
- homogenous turbulence,
- isotropic turbulence,
- structure function,
- passive grid
- hot wire anemometry,
- wind tunnel ...More
How to Cite
Abstract
By using an active grid and a passive grid, a homogenous and isotropic turbulent flow was characterized by studying its longitudinal structure functions and transverse 〉 and where u is the longitudinal velocity fluctuation, and v is the fluctuation of the transverse velocity, as a function of the Reynolds number for orders, n, between 2 and 8. The turbulence was generated in a wind tunnel with 91 × 91 cm2 in cross-section and 9,14 m in length. The velocity field was measured with hot-wire anemometry with TSI 1241 and TSI 1210 sensors manufactured with an alloy of platinum and rhodium of 2,54 diameter. The results indicated that the exponents of scale vary according to ; if increases, the difference between the exponents of the structure functions and the exponents predicted by the K41 theory also increases.
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References
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