Length/diameter

Type Width Thicknes Length Diameter afSide DnU Hole Depth al DriU Hole Depth Pilch... 

Though by no means a complete theory, this is at least a reasonable explanation of the Knudsen minimum, and it then remains to explain why the minimum is not observed for flow through porous media. Pollard and Present attributed this to the limited length/diameter ratio of the channels in a typical porous medium and gave a plausible argument in favor of this view. 

In a later, but less detailed analysis of flow in the intermediate pressure range, Hiby and Pahl [37] suggested that the minimum should be absent when the length/diameter ratio of a capillary is less than about sixteen. Since it is likely that this is the case for the channels in most porous media of... 

Simha equation), where a/b is the length/diameter ratio of these cigarshaped particles. Doty et al.t measure the intrinsic viscosity of poly(7-benzyl glutamate) in a chloroform-formamide solution and obtained (approximately) the following results ... 

There are three kinds of metal-matrix composites distinguished by type of reinforcement particle-reinforced MMCs, short fiber- or whisker-reinforced MMCs, and continuous fiber- or sheet-reinforced MMCs. Table 1 provides examples of some important reinforcements used in metal-matrix composites as well as their aspect (length/diameter) ratios and diameters. 

These fibrous minerals share several properties which qualify them as asbestiform fibers (/) they are found in large clusters which can be easily separated from the host matrix or cleaved into thinner fibers (1) (2) the fibers exhibit high tensile strengths (1) (J) they show high length diameter ratios, from a minimum of 20 up to >1000 (1) (4) they are sufficiendy dexible to be spun and (5) macroscopicaHy, they resemble organic fibers such as cellulose (2). 

The L/D (length-diameter) ratio found most efficient in commercial practice hes Between 4 and 10. If the length calculated previously does not fall within these Emits, another value of Nt which will place L/D in the proper range may be computed. 

The copolymers are used in the manufacture of filaments. These may be extruded from steam-heated extruders with a screw compression ratio of 5 1 and a length/diameter of 10 1. The filaments are extruded downwards (about 40 at a time) into a quench bath and then round drawing rollers which cause a three- to four-fold extension of the filaments and an increase in strength from about 10000 to 36 000 Ibf/in (70-250 MPa). The filaments are used for deck chair fabrics, car... 

The thermal expansion and contraction of solids can also have safety implications. For a given material the amount of its linear expansion, or contraction, in one direction is directly related to temperature and its original size (i.e. length, diameter, circumference). Thus ... 

Reynolds number for the fluid being released. For sharp edged orifices with Reynolds numbers approaching 30,000, it approaches 0.61. For these conditions, the exit velocity of the fluid is independent of the size of the hole. For a rounded opening, Cj approaches 1. For a short section if pipe (length/diameter > 3), Cj = 0.81. For cases where is unknown or uncertain use C. = I i[Pg.338]

Most investigators used tubes open only at the end opposite the point of ignition. For tubes with very large aspect ratios (length/diameter), the positive feedback mechanism resulted in a transition to detonation for many fuels, even when the tubes were unobstructed. Introduction of obstacles into tubes reduced considerably the distance required for transition to detonation. 

The nomographs (Figures 7-63A-D) apply for ves-sel/equipment with length/diameter ratio (L/D) of 5 or less, otherwise, a danger of detonation may exist. For equipment with L/D > 5, refer to NFPA-68, Chapter 8 [27], and NFPA-69 [55]. 

Ouisde Upset Dd Outride Inside Length Diameter, Dismeter Width of... 

Cylindrical bearings have solid or helically wound hollow cylindrically shaped rollers, which have an approximate length diameter ratio ranging from 1 1 to 1 3. They normally are used for heavy radial loads beyond the capacities of comparably sized radial ball bearings. 

Length Diameter Weight (miles) Speed (megatons)... 

The pipeline — length, diameter, inclination to the horizontal, necessity for... 

Figure 9.24. Effect of length diameter ratio on heat transfer coefficient...

The width and thickness of the block, and the number, length, diameter, and spacing of the channels are not independent. The geometric configuration requires that the number of channels in a row, be... 

Scale-up is non-geometric with length/diameter ratios varying from 2 1 to 30 1. The non-geometric scale-up helps to increase heat transfer area as reactor volume increases. 

Section Length diameter Cumulative Cumulative Diameter Number of... 

Determine the reactor length, diameter, Reynolds number, and scaling factor for pressure drop for the scaleup with constant heat transfer in Example 5.12. 

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