Next Article in Journal
Numerical Simulation of Non-Equilibrium Two-Phase Wet Steam Flow through an Asymmetric Nozzle
Next Article in Special Issue
Flow Anisotropy due to Thread-Like Nanoparticle Agglomerations in Dilute Ferrofluids
Previous Article in Journal
Urban Floods Adaptation and Sustainable Drainage Measures
Previous Article in Special Issue
Numerical Study of a 3D Eulerian Monolithic Formulation for Incompressible Fluid-Structures Systems
Article Menu

Article Versions

Export Article

Open AccessArticle
Fluids 2017, 2(4), 62; doi:10.3390/fluids2040062

Three-Dimensional Low Reynolds Number Flows near Biological Filtering and Protective Layers

1
Department of Mathematics, University of Tennessee Knoxville, 1403 Circle Drive, Knoxville, TN 37996, USA
2
Department of Mathematics, CB 3250, University of North Carolina, Chapel Hill, NC 27599, USA
3
Department of Biology, CB 3280, University of North Carolina, Chapel Hill, NC 27599, USA
4
School of Mechanical and Aerospace Engineering, Oklahoma State University, 218 Engineering North, Stillwater, OK 74078, USA
5
Department of Mathematics, Bucknell University, Lewisburg, PA 17837, USA
6
Department of Mathematics and Statistics, The College of New Jersey, 2000 Pennington Rd., Ewing, NJ 08628, USA
7
Army Research Office, 4300 S Miami Blvd, Durham, NC 27703, USA
*
Author to whom correspondence should be addressed.
Received: 5 September 2017 / Revised: 30 October 2017 / Accepted: 6 November 2017 / Published: 13 November 2017
(This article belongs to the Special Issue Mechanics of Fluid-Particles Systems and Fluid-Solid Interactions)
Download PDF [3743 KB, uploaded 13 November 2017]

Abstract

Mesoscale filtering and protective layers are replete throughout the natural world. Within the body, arrays of extracellular proteins, microvilli, and cilia can act as both protective layers and mechanosensors. For example, blood flow profiles through the endothelial surface layer determine the amount of shear stress felt by the endothelial cells and may alter the rates at which molecules enter and exit the cells. Characterizing the flow profiles through such layers is therefore critical towards understanding the function of such arrays in cell signaling and molecular filtering. External filtering layers are also important to many animals and plants. Trichomes (the hairs or fine outgrowths on plants) can drastically alter both the average wind speed and profile near the leaf’s surface, affecting the rates of nutrient and heat exchange. In this paper, dynamically scaled physical models are used to study the flow profiles outside of arrays of cylinders that represent such filtering and protective layers. In addition, numerical simulations using the Immersed Boundary Method are used to resolve the three-dimensional flows within the layers. The experimental and computational results are compared to analytical results obtained by modeling the layer as a homogeneous porous medium with free flow above the layer. The experimental results show that the bulk flow is well described by simple analytical models. The numerical results show that the spatially averaged flow within the layer is well described by the Brinkman model. The numerical results also demonstrate, however, that the flow can be highly three-dimensional with fluid moving into and out of the layer. These effects are not described by the Brinkman model and may be significant for biologically relevant volume fractions. The results of this paper can be used to understand how variations in density and height of such structures can alter shear stresses and bulk flows.
Keywords: immersed boundary method; porous flow; trichomes; glycocalyx; leakiness; filtering layers immersed boundary method; porous flow; trichomes; glycocalyx; leakiness; filtering layers
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Strickland, C.; Miller, L.; Santhanakrishnan, A.; Hamlet, C.; Battista, N.A.; Pasour, V. Three-Dimensional Low Reynolds Number Flows near Biological Filtering and Protective Layers. Fluids 2017, 2, 62.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Fluids EISSN 2311-5521 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top