Geometric design

Cyclone Efficiency. Most cyclone manufacturers provide grade-efficiency curves to predict overall collection efficiency of a dust stream in a particular cyclone. Many investigators have attempted to develop a generalized grade-efficiency curve for cyclones, eg, see (159). One problem is that a cyclone s efficiency is affected by its geometric design. Equation 15 was proposed to calculate the smallest particle size collectable in a cyclone with 100% efficiency (157). 

When macro-scale variables are involved, every geometric design variable can affect the role of shear stresses. They can include such items as power, impeller speed, impeller diameter, impeller blade shape, impeller blade width or height, thickness of the material used to make the impeller, number of blades, impeller location, baffle location, and number of impellers. 

Whirl outlets, either radial or linear, that have geometrically designed aperture chambers... 

A number of attempts to relate the geometric design parameters of a cyclone to the pressure drop have led to various empirical formulas for the loss factor Cf. One of the simplest formulas is an expression proposed by Sheperd and Lapple ... 

The Kenics STATIC MIXER unit is a series of fixed, helical elements enclosed within a tubular housing. The fixed geometric design of the unit produces the following unique patterns of flow division and radial mixing simultaneously. 

Faulty geometrical design is a major factor in the corrosion of ferrous metals. A design may be sound from the structural and aesthetic points of view, but if it incorporates features that tend to promote corrosion, then unnecessary maintenance costs will have to be met throughout the life of the article, or early failure may occur. 

There are different techniques that have been used for over a century to increase the modulus of elasticity of plastics. Orientation or the use of fillers and/or reinforcements such as RPs can modify the plastic. There is also the popular and extensively used approach of using geometrical design shapes that makes the best use of materials to improve stiffness even though it has a low modulus. Structural shapes that are applicable to all materials include shells, sandwich structures, and folded plate structures (Fig. 3-8). These widely used shapes employed include other shapes such as dimple sheet surfaces. They improve the flexural stiffness in one or more directions. 

Merchuk, J. C., Ladwa, N., Cameron, A., Bulmer, M., and Pickett, A., Concentric-Tube Airlift Reactors Effects of Geometrical Design on Performance, AIChE J., 40 1105 (1994)... 

Vapor transport into the condenser depends strongly on the geometric design of the plant. Under favorable conditions, and including a valve between chamber and condenser, a vapor speed of 60-90 m/s can be expected, resulting in a pressure drop between the chamber and condenser of a factor of 2, as an order of magnitude. 

Qark, J. Parametric Curves, Surfaces, and Volumes in Computer Graphics and Con uter Aided Geometric Design, Technical Report No. 221, Con uter Systems Laboratory, Stanford University, 1981. 

FIG. 7. Schematic diagram showing the geometric designs of buccal delivery devices (from Ref 97). 

From experiments, equations have been derived that enable calculation of the minimum velocity in the nozzle, the nozzle velocity, and the Sauter diameter at the drop size minimum. They provide the basis for the correct design of a sieve tray [3,4]. Figure 9.4a shows the geometric design of sieve trays and their arrangement in an extraction column. Let us again consider toluene-phenol-water as the liquid system. The water continuous phase flows across the tray and down to the lower tray through a downcomer. The toluene must coalesce into a continuous layer below each tray and reaches... 

Logos and labels have now become part of the design In clothing. A T-shirt that used to have a picture or geometric design will now sport the company s logo. 

O Keeffe, M., Eddaoudi, M., Li, H., Reinecke, T., and Yaghi, O. M. (2000). Frameworks for extended solids Geometric design prinicples. J. Solid State Chem. 152, 3-20. 

Henceforth in this chapter, convection will be ignored. In other words, we shall treat only experiments in which forced convection is absent and in which natural convection is inhibited either by judicious geometric design of the cell or by the brevity of the experiment. 

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