Shear Effect on Pressure and Particle Acceleration in High-Reynolds-Number Turbulence

Abstract

Pressure fluctuations are an important ingredient in turbulence, however the variation of the pressure fluctuations inside a turbulent boundary layer is not well known and its generation not fully understood. One reason for this is the difficulty inherent in measuring the fluctuating pressure and, consequently, a lack of published experimental results of this quantity. In the present study, the new methods and improved measurement techniques are developed. Fluctuating pressure has been measured in turbulent boundary layer up to Rθ ≃ 20000 and in mixing layer up to Rλ ≃ O(10 3). In this report, the shear effect on the Kolmogorov’s -7/3 powerlaw scaling of pressure spectrum is discussed and the preliminary measurement of particle acceleration is reported.