The equation for the fluid velocity gradient along a Lagrangian trajectory immediately follows from the Navier–Stokes equation. However, such an equation involves two terms that cannot be determined from the velocity gradient along the chosen Lagrangian path: the pressure Hessian and the viscous Laplacian. A recent model handles these unclosed terms using a multilevel version of the recent deformation of Gaussian fields (RDGF) closure (Johnson & Meneveau,
Wellresolved direct numerical simulations (DNS) have been performed of the flow in a smooth circular pipe of radius
 Award ID(s):
 2031650
 NSFPAR ID:
 10476487
 Publisher / Repository:
 Cambridge University Press
 Date Published:
 Journal Name:
 Journal of Fluid Mechanics
 Volume:
 956
 ISSN:
 00221120
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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