학술논문

Universality of mean velocity profile in high Re-number turbulent boundary layer / 高レイノルズ数乱流境界層における平均速度分布の普遍性に関する実験的研究
Document Type
Journal Article
Source
日本機械学会論文集 / Transactions of the JSME (in Japanese). 2021, 87(904):21-00280
Subject
High Reynolds-number universality
Mean velocity profile
Turbulent boundary layer
Language
Japanese
ISSN
2187-9761
Abstract
To better understand high Reynolds number zero-pressure-gradient turbulent boundary layers detailed hot-wire measurements of the mean and fluctuating streamwise velocity are made in RTRI ’s low-noise wind tunnel in Maibara Japan. The momentum thickness Reynolds number is up to approximately 8×104. Using the friction velocity measured by oil film interferometry, mean velocity profile shows a clear log-law region. The turbulent intensity profile also shows the log-law scaling predicted by attached eddy model. However, the log-regions of mean and turbulent intensity do not match with each other. Kármán constant κ, additive constant B, and wake parameter Π are evaluated as 〈κ〉 = 0.385 ± 0.003, 〈B〉 = 4.26 ± 0.15, 〈B1〉 = −1.077 ± 0.089, 〈Π〉 = 0.455 ± 0.025, and they relate closely with each other by simple equation.