Document Detail


Vortical and acoustical mode coupling inside a porous tube with uniform wall suction.
MedLine Citation:
PMID:  16018449     Owner:  NLM     Status:  PubMed-not-MEDLINE    
Abstract/OtherAbstract:
This paper considers the oscillatory motion of gases inside a long porous tube of the closed-open type. In particular, the focus is placed on describing an analytical solution for the internal acoustico-vortical coupling that arises in the presence of appreciable wall suction. This unsteady field is driven by longitudinal oscillatory waves that are triggered by small unavoidable fluctuations in the wall suction speed. Under the assumption of small amplitude oscillations, the time-dependent governing equations are linearized through a regular perturbation of the dependent variables. Further application of the Helmholtz vector decomposition theorem enables us to discriminate between acoustical and vortical equations. After solving the wave equation for the acoustical contribution, the boundary-driven vortical field is considered. The method of matched-asymptotic expansions is then used to obtain a closed-form solution for the unsteady momentum equation developing from flow decomposition. An exact series expansion is also derived and shown to coincide with the numerical solution for the problem. The numerically verified end results suggest that the asymptotic scheme is capable of providing a sufficiently accurate solution. This is due to the error associated with the matched-asymptotic expansion being smaller than the error introduced in the Navier-Stokes linearization. A basis for comparison is established by examining the evolution of the oscillatory field in both space and time. The corresponding boundary-layer behavior is also characterized over a range of oscillation frequencies and wall suction velocities. In general, the current solution is found to exhibit features that are consistent with the laminar theory of periodic flows. By comparison to the Sexl profile in nonporous tubes, the critically damped solution obtained here exhibits a slightly smaller overshoot and depth of penetration. These features may be attributed to the suction effect that tends to attract the shear layers closer the wall.
Authors:
T A Jankowskia; J Majdalani
Related Documents :
11105319 - Mixing time analysis of a sonochemical reactor.
19290609 - Enabling ultrahigh plastic flow and work hardening in twinned gold nanowires.
17124139 - Numerical simulation of the spontaneous penetration of liquids into cylindrical capilla...
20191559 - Nonlinear smoluchowski velocity for electroosmosis of power-law fluids over a surface w...
16485929 - Classical and quantum diffusion in the presence of velocity-dependent coupling.
12736239 - Robustness of the tuning of fly visual interneurons to rotatory optic flow.
23832629 - Charmm36 all-atom additive protein force field: validation based on comparison to nmr d...
23042699 - Circular dichroism from chiral nanomaterial fabricated by on-edge lithography.
17059879 - Analyzing and shaping human attentional networks.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  The Journal of the Acoustical Society of America     Volume:  117     ISSN:  0001-4966     ISO Abbreviation:  J. Acoust. Soc. Am.     Publication Date:  2005 Jun 
Date Detail:
Created Date:  2005-07-15     Completed Date:  2005-12-14     Revised Date:  2006-12-27    
Medline Journal Info:
Nlm Unique ID:  7503051     Medline TA:  J Acoust Soc Am     Country:  United States    
Other Details:
Languages:  eng     Pagination:  3448-58     Citation Subset:  -    
Affiliation:
University of Tennessee Space Institute, Tullahoma, Tennessee 37388, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Ultrasonic particle concentration in a line-driven cylindrical tube.
Next Document:  Torsional wave experiments with a new magnetostrictive transducer configuration.