Document Detail

Dynamical evolution of volume fractions in multipressure multiphase flow models.
MedLine Citation:
PMID:  18643369     Owner:  NLM     Status:  PubMed-not-MEDLINE    
Compared to single-pressure models, multipressure multiphase flow models require additional closure relations to determine the individual pressures of the different phases. These relations are often taken to be evolution equations for the volume fractions. We present a rigorous theoretical framework for constructing such equations for compressible multiphase mixtures in terms of submodels for the relative volumetric expansion rates DeltaE_{i} of the phases. These quantities are essentially the rates at which the phases dynamically expand or contract in response to pressure differences, and represent the general tendency of the volume fractions to relax toward values that produce local pressure equilibrium. We present a simple provisional model of this type in which DeltaE_{i} is proportional to pressure differences divided by the time required for sound waves to traverse an appropriate characteristic length. It is shown that the resulting approach to pressure equilibrium is monotonic rather than oscillatory, and occurs instantaneously in the incompressible limit.
C H Chang; J D Ramshaw
Related Documents :
7757149 - What happens during vocal warm-up?
12160019 - Influence of dissolved oxygen content on multibubble sonoluminescence with ambient-pres...
7258819 - Lung sounds in patients with emphysema.
20058989 - Unsteady laryngeal airflow simulations of the intra-glottal vortical structures.
24231929 - Soccer boots elevate plantar pressures in elite male soccer professionals.
19129709 - Aerodynamics of the pseudo-glottis.
37349 - Pressor response during cystomanometry in spinal injury patients complicated with detru...
22540919 - Pressure-reduction and preservation in custom-made footwear of patients with diabetes a...
10978259 - Reduction of aortic wall motion inhibits hypertension-mediated experimental atheroscler...
Publication Detail:
Type:  Journal Article     Date:  2008-06-10
Journal Detail:
Title:  Physical review. E, Statistical, nonlinear, and soft matter physics     Volume:  77     ISSN:  1539-3755     ISO Abbreviation:  Phys Rev E Stat Nonlin Soft Matter Phys     Publication Date:  2008 Jun 
Date Detail:
Created Date:  2008-07-22     Completed Date:  2008-08-22     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101136452     Medline TA:  Phys Rev E Stat Nonlin Soft Matter Phys     Country:  United States    
Other Details:
Languages:  eng     Pagination:  066305     Citation Subset:  -    
Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

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

Previous Document:  Intermittent particle distribution in synthetic free-surface turbulent flows.
Next Document:  Geometrical and transport properties of random packings of polydisperse spheres.