title: Dynamic shear stress in parallel-plate flow chambers.
abstract: An in vitro model using a parallel-plate fluid flow chamber is supposed to simulate in vivo fluid shear stresses on various cell types exposed to dynamic fluid flow in their physiological environment. The metabolic response of cells in vitro is associated with the wall shear stress. However, parallel-plate flow chambers have not been characterized for dynamic fluid flow experiments. We use a dimensionless ratio h / lambda(v), in determining the exact magnitude of the dynamic wall shear stress, with its oscillating components scaled by a shear factor T. It is shown that, in order to expose cells to predictable levels of dynamic fluid shear stress, two conditions have to be met: (1) h / lambda(v) < 2, where h is the distance between the plates and lambda(v) is the viscous penetration depth; and (2) f(0) < f(c) / m, where the critical frequency f(c) is the upper threshold for this flow regime, m is the highest harmonic mode of the flow, and f(0) is the fundamental frequency of fluid flow.
authors.affiliation: Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam-Vrije Universiteit, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands. rg.bacabac.ocb.acta@med.vu.nl
authors.forename: Rommel G
authors.initials: RG
authors.lastname: Bacabac
authors.forename: Theo H
authors.initials: TH
authors.lastname: Smit
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Cowin
authors.forename: Jack J W A
authors.initials: JJ
authors.lastname: Van Loon
authors.forename: Frans T M
authors.initials: FT
authors.lastname: Nieuwstadt
authors.forename: Rob
authors.initials: R
authors.lastname: Heethaar
authors.forename: Jenneke
authors.initials: J
authors.lastname: Klein-Nulend
mesh_terms: D000818:Animals; D001826:Body Fluids / Q000502:physiology*; D002468:Cell Physiological Phenomena; D003198:Computer Simulation; D004056:Differential Threshold; D004867:Equipment Design; D006801:Humans; D008954:Models, Biological; D010827:Physiology / Q000295:instrumentation*; D013314:Stress, Mechanical; D014783:Viscosity