Discovery of the zeroth law of helicity spectrum in the pre-inertial range of wall turbulence

Ali, S K Zeeshan and Dey, Subhasish (2022) Discovery of the zeroth law of helicity spectrum in the pre-inertial range of wall turbulence. Physics of Fluids, 34 (7). pp. 1-6. ISSN 1070-6631

Text
Physics_of_Fluids.pdf - Published Version
Available under License Creative Commons Attribution.
Download (1MB)

Abstract

We report an unprecedented existence of the zeroth law of helicity spectrum (i.e., the helicity spectrum becomes independent of the wavenumber) in the transition from production range to inertial range, herein termed the pre-inertial range, of wall turbulence. The zeroth law is explained by the superposition effect of the forward joint cascade of energy and helicity caused by twisting and stretching of wall-attached superstructures in an equilibrium layer. The phenomenological model perfectly predicts the zeroth law in the pre-inertial range. Experimental data support the existence of the zeroth law. © 2022 Author(s).

[error in script]

IITH Creators:

IITH Creators	ORCiD
Ali, S K Zeeshan	UNSPECIFIED

Item Type:

Article

Additional Information:

S.Z.A. acknowledges the Institute Seed Grant of IIT Hyderabad in carrying out this research. S.D. acknowledges the J C Bose Fellowship Award (Funded by DST | Science and Engineering Research Board (SERB), Grant Reference No. JCB/2018/000004) in pursuing this work. We thank O. Chkhetiani for providing the experimental data of helicity spectrum.

Uncontrolled Keywords:

Data support; Energy; Equilibrium layers; Helicities; Inertial ranges; Phenomenological models; Spectra's; Superposition effect; Wall turbulence; Wave numbers

Subjects:

Civil Engineering
Civil Engineering > Water resources engineering

Divisions:

Department of Civil Engineering

Depositing User:

. LibTrainee 2021

Date Deposited:

21 Jul 2022 12:08

Last Modified:

21 Jul 2022 12:08

URI:

http://raiithold.iith.ac.in/id/eprint/9851