Thermo-capillary flow

So, the estimation just performed shows that in the above-mentioned problem of a one-dimensional thermo-capillary flow of a thin layer, surface tension plays the mane role in formation of the flow. 

Pore structure of freeze dried PHEMA seafFolds was characterized on a mereuiy poro-simeter Pascal 140 and 440 (Thermo Finigan, Rodano, Italy). It woiks in two pressure intervals, 0-400 kPa and 1-400 MPa, allowing determination of meso- (2-50 nm), macro- (50-1000 nm) and small snperpores (1-116 pm). The pore volnme and most freqnent pore diameter were calculated under the assumption of a cyUndrical pore model by the PASCAL program. It employed Washburn s equation describing capillary flow in porous materials [33]. The volumes of bottle and spherical pores were evaluated as the difference between the end values on the volume/pressure curve. Porosity was calculated according to Equation 2, where cumulative pore volume (meso-, macro- and small supeipores) from mercury porosimetry was used for R. 

Fig. 5.9 Design of the chip-based enzyme ESI-MS assay. MS instrument Ion-trap mass spectrometer (LCQ Deca, Thermo Electron). I Sample components/inhibitors injected by flow injection or eluting from capillary HPLC column. E Infusion pump delivering the enzyme cathepsin B. S infusion pump delivering the substrate Z-FR-AMC. Micro-chip design Vrije Universiteit Amsterdam. Micro-chip production Micronit Microfluidics BV (Enschede, The Netherlands).

TWO PHASE FLOW IN CAPILLARY POROUS THERMO-ELASTIC MATERIALS... 

Abstract In this contribution, the coupled flow of liquids and gases in capillary thermoelastic porous materials is investigated by using a continuum mechanical model based on the Theory of Porous Media. The movement of the phases is influenced by the capillarity forces, the relative permeability, the temperature and the given boundary conditions. In the examined porous body, the capillary effect is caused by the intermolecular forces of cohesion and adhesion of the constituents involved. The treatment of the capillary problem, based on thermomechanical investigations, yields the result that the capillarity force is a volume interaction force. Moreover, the friction interaction forces caused by the motion of the constituents are included in the mechanical model. The relative permeability depends on the saturation of the porous body which is considered in the mechanical model. In order to describe the thermo-elastic behaviour, the balance equation of energy for the mixture must be taken into account. The aim of this investigation is to provide with a numerical simulation of the behavior of liquid and gas phases in a thermo-elastic porous body. 

Two Phase Flow in Capillary Porous Thermo-Elastic Materials... 

A commercial instrument for extensional viscosity measurements is currently offered by the Thermo Electron Corporation [40], The device uses capillary breakup techniques and is called the Haake CaBER . Vilastic Scientific, Inc. also offers an orifice attachment to their oscillatory rheometer for extensional viscosity determinations [41,42], The principle of operation of the rheometer is oscillatory tube flow [43,44], Dynamic mechanical properties can be determined... 

To study the flow within the capillaries, the aqueous phase was seeded with fluorescent microsphere suspensions at 1 % concentration by weight (Thermo Scientific). The fluorescent micro-spheres are made of polystyrene and were dyed with red or blue fluorescent dyes. The refractive index and the density are 1.59 and 1.06 g cm, respectively. The spectral properties of the fluorescent microspheres are shown in Table 3.3. The size of the particles varied between 1 and 3.2 pm depending on the channel size. 

Temperature and Heat Flux Driven Flow A fourth mode of transport that has been shown to drive water flux in the membrane is heat flux driven flow. As a general rule, water will move through the membrane toward a colder location. This occurs in a freezing process due to capillary forces [20, 21], and nonfreezing processes [22,23]. The nonfrozen mode of transport is poorly understood but is likely a result of the combined effects of capillary pressure change with temperature and thermo-osmosis in membranes. 

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