Reynolds number, defined

TurbulentPremixedFlames. Combustion processes and flow phenomena are closely coimected and the fluid mechanics of a burning mixture play an important role in forming the stmcture of the flame. Laminar combusting flows can occur only at low Reynolds numbers, defined as... 

For banks of staggered tubes, the friction factor for isothermal flow is obtained from Fig. (6-42). Each fence (group of parametric curves) represents a particular Reynolds number defined as... 

Impeller Reynolds Number The presence or absence of turbulence in an impeller-stirred vessel can be correlated with an impeller Reynolds number defined... 

The secondary flows from natural convection can become larger than the primary flow, so it seems likely that the secondary flows might become turbulent or nonsteady. Shown in Tables 1 and 2 are the dimensionless groups at the inlet and outlet, based on cup-average quantities, as well as the Reynolds numbers for the primary and secondary flows (Reynolds numbers defined in terms of the respective total mass flowrate, the viscosity and the ratio of tube perimeter to tube area). 

The relationship between the various length scales can be best understood by looking at their dependence on the turbulence Reynolds number defined in terms of the turbulent kinetic energy k, the turbulent dissipation rate e, and the kinematic viscosity v by... 

The functions f5-f8 and ip5-ip8 may be determined from a system of two ordinary differential equations. In addition, the form of the functions /7, /8, Prandtl number. It, is interesting that along a laminar ascending flow, in both the plane and radially-symmetric cases, the Reynolds number (defined as ub/v) increases as x3/5 and x1/2, respectively.1 Consequently, at a sufficient height disruption of the laminar flow and transition to turbulent flow should take place. 

R Overall electric resistance of the membrane stack (O) Re Reynolds number (defined in Table III dimensionless) RErs Electric resistance of electrode rinsing solution (O)... 

The optimal Reynolds number defines the operating conditions at which the cylindrical system performs a required heat and mass transport, and generates the minimum entropy. These expressions offer a thermodynamically optimum design. Some expressions for the entropy production in a multicomponent fluid take into account the coupling effects between heat and mass transfers. The resulting diffusion fluxes obey generalized Stefan-Maxwell relations including the effects of ordinary, forced, pressure, and thermal diffusion. 

When Boussinesq approximation is adopted in full conservation equations, it is noted that the effect of buoyancy force appears in terms of GrjRe where Gr is the Grashof number and Re is the Reynolds number defined in terms of appropriate length, velocity and temperature scales. However, Leal et al. (1973) and Sparrow Minkowycz (1962) have shown that the equivalent buoyancy parameter with the boundary layer assump-... 

The Reynolds number Re = wm 6/z/L for the condensation on a vertical tube can, due to the mass balance M = wm dn 8 gL and with r/L = i/LgL, also be written as Re = M/(d,TT i]L ). As the tube diameter d, on which the calculations from Fig. 4.12 are based, is much larger than the assumed thickness of the film, the curvature of the condensate film has no effect on the heat transfer. The results also hold for condensation on a vertical flat plate, with the Reynolds number defined in (4.38). 

Subsequently Saffman [125, 126] derived an expression for the lift force on a particle in a shear flow, as illustrated in Fig 5.5. He incorporated three different Reynolds numbers defined by ... 

The reader may be surprised not to And a Reynolds number defined speciflcally for the disperse phase. This is because the disperse-phase viscosity is well defined only for Knp 1 (i.e. the collision-dominated or hydrodynamic regime). In this limit, Vp oc oc Knp/Map so that the disperse-phase Reynolds number would be proportional to Map/Krip when Map < 1. However, in many gas-particle flows the disperse-phase Knudsen number will not be small, even for ap 0.1, because the granular temperature (and hence the collision frequency) will be strongly reduced by drag and inelastic collisions. In comparison, molecular gases at standard temperature and pressure have KUp 1 even though the volume fraction occupied by the molecules is on the order of 0.001. This fact can be... 

V being the dynamical viscosity and R being the Reynolds number defined by... 

Yang etal. report an experimental and computational study of mass transfer to a channel wall downstream of a cylinder. The rate of mass transfer was recorded at various locations. Ferricyanide reduction at a mass-transfer-controlled rate from an electrolyte containing a large amount of KCl was used for the experimental measurements. A diagram of the cell is shown in Fig. 7. A cylinder of diameter d is placed a distance b from the bottom wall, and a working electrode of length 2L is placed at a distance x downstream of the center of the cylinder. The fluid flow can be characterized with a Reynolds number defined as... 

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