Equivalent cylinder

Nitrogen generator (or equivalent cylinder with regulator) for heater/evaporator... 

Theoretical geometrical idealizations can be divided into two categories equivalent cylinder models and cell models. In the former, the plug or diaphragm is interpreted as a collection of parallel cylinders of given average radius (a). In cell models, the porous system is modelled as a collection of, usually homodlsperse spherical, particles, organized into some three-dimensional array. 

U = velocity defined as 1/2(17 + U2) where 1/, and U2 are the individual velocities of the moving surfaces R = radius of equivalent cylinder L = load per unit width... 

E = elastic modulus of equivalent cylinder (flat surface assumed completely rigid)... 

The first of these is the Reynolds equation in its simplest form the second equation covers the variation of viscosity as a function of pressure the third expression gives the film thickness, where R is the radius of the equivalent cylinder and i j is the combined displacement of the two solid boundaries. The equivalent cylinder treatment is a way of generalizing and simplifying the geometry of curvilinear boundaries if x is small enough relative to R,... 

E being Young s modulus and u Poisson s ratio. Figure 3-6 illustrates the displacement of the boundary of the equivalent cylinder by a simple Hertzian pressure distribution through the oil film of thickness h. The geometrical coordinate x is measured from the center line in either direction. Each element of load p )di along the entire line of the boundary from 6 to 2 acts at the location x to contribute to the normal displacement ili at that location as calculated by Eqn 3-52. 

Tortuosity In porosimetry evaluations, experimental data tend to be interpreted in terms of a model in which the porous medium is taken to comprise a bundle of cylindrical pores having radius r. If the Young-Laplace equation is then applied to the data, an effective value of r can be calculated, even though this model ignores the real distribution of irregular channels. The calculated r value is sometimes considered to represent the radius of an equivalent cylinder or, alternatively, is termed the tortuosity. 

Chopper units in the anteroventral cochlear nucleus Banks and Sachs [1991] constructed an equivalent cylinder model of chopper units in the anteroventral cochlear nucleus. The model of the soma membrane included a fast sodium current, a delayed rectifier current, a linear leakage current, and inhibitory and excitatory synaptic currents using the Rail a-wave model. 

De = outside diameter of assumed equivalent cylinder for design of cones or conical sections, in. 

Maximum distance along shell from junction to centroid of ring, in Length of cone along shell, in Length of equivalent cylinder for external pressure, in... 

N = Factor at small end if this is a LOS P = Internal pressure, psig Px = External pressure, psig Qli-4 = Axial load per unit circumference including pressure, Lbs/in-circ tsi, ts2 = Thickness required, shell, in be = Thickness required, cone, in te = Thickness, equivalent cylinder for large end, in... 

For conical heads having an intermediate apex angle (15° to 120°) the same procedure is followed except that the diameter at the large end of the cone is taken as the length of the equivalent cylinder if no circumferential stiffeners are used. If circumferential stiffeners are used, the procedure is the same as for stiffened cones with apex angl of 1 than 45°, described above. 

Radius of equivalent cylinder adjacent to rigid plane. 

This equation that expresses the cone in terms of an equivalent cylinder of thickness U and length L is analogous to Eq. 6.42 for cylindrical shells. Thus the ASME Code, VIII-1, applies the same equations for the design of cylindrical shells under external pressure for the design of cones with applicable values of U and Le. 

Around each PVD an equivalent cylinder is assumed with a radius of 1.05 times or 1.13 times the distance between the PVDs for respectively a triangular or a square spacing (see Figure D.6). 

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