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Laminar flow between parallel plates

The problem of axial conduction in the wall was considered by Petukhov (1967). The parameter used to characterize the effect of axial conduction is P = (l - dyd k2/k ). The numerical calculations performed for q = const, and neglecting the wall thermal resistance in radial direction, showed that axial thermal conduction in the wall does not affect the Nusselt number Nuco. Davis and Gill (1970) considered the problem of axial conduction in the wall with reference to laminar flow between parallel plates with finite conductivity. It was found that the Peclet number, the ratio of thickness of the plates to their length are important dimensionless groups that determine the process of heat transfer. [Pg.171]

Table IV includes theoretical transition times (C2, R14, SI7c) in laminar flow between parallel plates, following a concentration step at the wall (Leveque mass transfer). Clearly, in laminar flow (Re 100 or lower), transition times are comparable to those in laminar free convection. Here, however, the dependence on concentration (through the diffusivity) is weak. The dimensionless time variable in unsteady-state mass transfer of the Leveque type is... Table IV includes theoretical transition times (C2, R14, SI7c) in laminar flow between parallel plates, following a concentration step at the wall (Leveque mass transfer). Clearly, in laminar flow (Re 100 or lower), transition times are comparable to those in laminar free convection. Here, however, the dependence on concentration (through the diffusivity) is weak. The dimensionless time variable in unsteady-state mass transfer of the Leveque type is...
Figure 2.1 Velocity profile of laminar flow between parallel plates moving at different velocities. Figure 2.1 Velocity profile of laminar flow between parallel plates moving at different velocities.
Laminar flow between parallel plates can be described by (30)... [Pg.69]

K. Sheshadri and F.A. Williams. Laminar Flow between Parallel Plates with Injection of a Reactant at High Reynolds Number. Int. J. Heat Mass Transf., 21 251-253,1978. [Pg.835]

For laminar flow between parallel plates, the results of Sparrow [15] are summarised in figure 5. [Pg.33]

Spurk (1997) derived closed-form solutions for the average flow velocity v between parallel plates and in full ducts. For laminar flow between parallel plates relationships between viscosity, geometry, pressure gradient and mean flow velocity are given as ... [Pg.31]

R.O.C. Guedes, R.M. Cotta, and N.C.L. Bram, Conjugated Heat Transfer in Laminar Flow Between Parallel - Plates Channel, 10th Brazilian Congress of Mechanical Engineering, Rio de Janeiro, Brazil, 1989. [Pg.81]

R. D. Cess, and E. C. Shaffer, Heat Transfer to Laminar Flow between Parallel Plates with a Prescribed Wall Heat Flux, Appl. Sci. Res., (A8) 339-344,1959. [Pg.432]

Similarly the limiting trajectory equations for laminar flow between parallel plates or in shallow trays and for uniform flow (i.e. u/Vo = 1) are of the foim ... [Pg.247]

For laminar flow between parallel plates with a spacing of 2h, the average mass transfer coefficient is. [Pg.756]

Chow, L.C., Campo, A., Tien, C.L., 1980. Heat transfer characteristics for laminar flow between parallel plates with suction. Int. J. Heat Mass Transf. 23, 740-743. [Pg.427]

Example 3.6 Combined Drag and Pressure Flow between Parallel Plates In this example we examine the isothermal, laminar, steady, fully developed combined pressure and drag... [Pg.117]

Pressure Flow Calculations Using the Equivalent Newtonian Viscosity6 Consider fully developed isothermal laminar pressure flow between parallel plates of a shear-thinning liquid with a flow curve fitted to the following polynomial relationship above the shear rate )>0 ... [Pg.138]

Consider laminar fluid flow between parallel plates with a uniform wall temperature. A fully developed parabolic velocity profile, Eq. (8.89), is assumed as in the previous case. For the temperature profile, the following polynomial is assumed ... [Pg.133]

A smaller r results in better distributive mixing in the laminar flow field. The shear rate and residence time in shear flow between parallel plates where one plate is moving can be written as ... [Pg.269]

Bulk Velocity for Flow Between Parallel Plates. A fluid flowing in laminar flow in the x direction between two parallel plates has a velocity profile given by the following. [Pg.106]

Doughty, J.R., Perkins, H.C., 1970. Hydrodynamic entry length for laminar flow between parallel porous plates. ASME J. Appl. Mech. 37, 548-550. [Pg.430]

Terrill, R.M., Walker, G., 1967. Heat and mass transfer in laminar flow between parallel porous plates. Appl. Sci. Res. 18, 193-220. [Pg.454]

FIGURE 7.1 Arrangement for producing laminar, unidirectional shear flow between parallel plates (see Table 7.1). [Pg.268]

The laminar flow assumption eliminates the non-linear term in the partial differential equations system (3.3), thus significantly reducing the computational cost. In addition, the present formulation often admits an exact solution. For example, in the case of an incompressible 2D laminar flow between two motionless parallel plates (i.e. planar SOFC configuration of Figure 3.1), Equation (3.29) reduces to ... [Pg.60]

Consider a fluid that is contained between parallel plates as shown in Figure 6.2. The fluid can be made to flow as follows. If the upper plate is moved, it exerts a force across the nearest plane layer of fluid. Depending on the force per unit area (F/A) some deformation is produced (parallel to the plane). If the fluid is visualized as a set of thin plane layers, the uppermost layer will move with the plate while the lowermost layer remains motionless (no-slip condition). Intermediate layers will have intermediate velocities. The flow situation just described is termed laminar flow (turbulent flow is discussed in Section 10.3.1). The distance between adjacent layers is dy and between adjacent layers, there exists a velocity difference, dV, thus a velocity gradient dV/dy. This velocity gradient arises out of a competition between the applied force per unit area (F/A) and an internal resistance provided by the fluid,... [Pg.156]

Consider the fully developed laminar flow between two parallel plates at a distance 2a apart. Find the expression for the velocity profile and the friction factor. [Pg.134]

Obtain the steady-state, fully developed velocity distribution for laminar flow between two parallel plates, in the absence of body forces. [Pg.134]

Systematically find the expression for the temperature distribution and the Nusselt number for laminar flow between two large parallel plates in the region of fully developed velocity and temperature profiles for a uniformly applied wall heat flux. [Pg.135]

Consider constant-property, fully developed laminar flow between two large parallel plates, i.e., in a wide plane duct. One plate is adiabatic and the other is isothermal and the velocity is high enough for viscous dissipation effects to be significant. Determine the temperature distribution in the flow. [Pg.225]

The above evidence establishes that fracturing and seismic behavior can extend well into the zone of mid to lower crustal metamorphism at rock pressures of —0.5-1 GPa. Veins preserve a valuable record of this brittle deformation they are fractures in which mineral mass has been deposited. The most common vein-forming minerals are quartz, calcite, and the feldspars, but a huge variety of other minerals are also observed. Fractures tend to focus flow, because they are zones of elevated permeability. Fracture flow is commonly approximated using the well-known expression from fluid mechanics for laminar flow between two parallel plates (e.g., White, 1979). For a set of parallel fractures, the flux is approximated by (e.g., Norton and Knapp, 1977) ... [Pg.1464]

This model assumes laminar flow between two perfectly smooth and parallel plates. However, Experiments have shown that the real mechanical aperture (E) and the hydraulic conducting aperture (e) are not equal. The cubic law (e = E) is only valid for very open fractures and/or for fractures with smooth fracture surfaces (low JRC). The mechanical aperture E can be converted into the hydraulic conducting aperture e, by using Eq. (2) (Barton et al., 1985) ... [Pg.139]

Prove that the flow of a liquid in laminar flow between infinite parallel flat plates is given by... [Pg.117]

Equations for concentration polarization have been derived for simple cases such as laminar flow of feed solution between parallel plates or inside hollow fibers. " Numerical solutions were required because of the developing concentration boundary layer and the gradual decrease in solution flow rate as permeation occurs. Exact solutions arc not available for the more important cases of flow outside hollow fibers or in the channels of a spiral-wound module, but an approximate analysis may still be helpful. [Pg.873]

Turbulence is inherently three-dimensional. If there is a pressure-driven laminar flow between two parallel plates, all the yelocity will be in one direction and all the velocity gradients will be in the direction perpendicular to the parallel plates. There is no velocity or velocity gradient in the direction perpendicular to these two directions. If we increase the Reynolds number enough for the flow to become turbulent, then we [will observe fluctuating turbulent velocity components in all three directions. ... [Pg.472]

In this paper, we analyze mass transfer in a parallel-plate mass exchanger with reactive membranes. We consider the case of fully developed, one-dimensional laminar flow between two membranes. Equilibrium carrier-facilitated transport of the solute takes place in the membrane phase. The effect of the diffusion and reaction parameters of the carrier-facilitated system on solute separation is Investigated. [Pg.40]

According to the Cubic Law, fracture is formed by the smooth, flat, infinite long parallel plates without filling medium, and the water flow between the plates is viscous incompressible flow which is permanent laminar flow. Thus, according to the basic principle of fluid mechanics, the discharge per unit width through the crack surface i.e. q can be calculated by the follow formula ... [Pg.1332]


See other pages where Laminar flow between parallel plates is mentioned: [Pg.171]    [Pg.204]    [Pg.319]    [Pg.171]    [Pg.204]    [Pg.319]    [Pg.188]    [Pg.30]    [Pg.197]    [Pg.654]    [Pg.372]    [Pg.30]   
See also in sourсe #XX -- [ Pg.28 ]




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