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Title: A Dual Scale Approach to Modeling Sub-Filter Velocities due to Shear-Induced Instabilities
A method to compute sub-filter velocities due to shear induced instabilities on a liquid-gas interface for use in a dual scale LES-DNS model is presented. The method reconstructs the sub-filter velocity field as the sum of a prescribed base velocity profile and a perturbation velocity field determined by the Orr-Sommerfeld equations. The base velocity profile is approximated as an error function appropriately scaled with flow parameters, and the perturbation velocity field is computed by solving the Orr-Sommerfeld equations with appropriate boundary and interface conditions. The perturbation velocities of the Orr-Sommerfeld equations are expanded into Chebyshev polynomials to create a linear eigenvalue problem as outlined by Schmid and Henningson (2001). Finally the eigenvalue problem is solved using a standard linear algebra package and used to evaluate the perturbation velocities. The Chebyshev method is tested under a variety of flow parameters and initial interface disturbances. Results are presented and compared against prior literature and asymptotic solutions.  more » « less
Award ID(s):
1803657
PAR ID:
10281846
Author(s) / Creator(s):
;
Date Published:
Journal Name:
ILASS-Americas 31st Annual Conference on Liquid Atomization and Spray Systems
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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