Aerodynamic properties

This invention relates generally to light weight covers used to increase the aerodynamic properties of wheels. More specifically, the present invention relates to covers for wheels capable of creating an aerodynamic effect by reducing the friction or drag across the surface of a wheel created by air flow. 

However, these systems fail to disclose an inexpensive means of easily improving the aerodynamic properties of a spoke wheel with minimal manual effort. As 65 can be seen, while any number of alternative wheel covers are available, these systems have certain shortcomings which have not yet been satisfied by the art. 

The present invention provides a wheel cover which improves the aerodynamic properties of the hub-rim-spoke wheels. The wheel cover of the present invention is preferably made of a light weight synthetic or natural polymer, fabric or paper film which is adhesively applied to a wheel through simple manual application. In turn, the aerodynamic wheel cover of the present invention may also be easily removed and replaced to allow on-road repairs of spoke, hub, or rim. 

The life and drag characteristics of a body in a flow are almost always given in terms of Cl and rather than the forces themselves, because the force coefficients are a more fundamental index of the aerodynamic properties. 

Turbine efficiency must be maintained over a wide range of Mach numbers and pitching, and efficiency depends in part upon a balance of mgged nozzle construction and the aerodynamic properties of the bucket blade profiles. 

A number of physicochemical properties are associated with aerosol droplets of particles, which impact upon their characteristics as aerosols. The most important of these may be related to the aerodynamic properties of aerosols [6],... 

Aerodynamic diameter Diameter of a unit density sphere (density = 1 g/cms) having the same aerodynamic properties as the particle in question. This means that particles of any shape or density will have the same aerodynamic diameter if their settling velocity is the same. 

As mentioned above, Eq. 5.15 implies that the aerodynamic diameter of a rod or fiber will be influenced very little by its length, being much more dependent on its cross-sectional diameter. Hence fibers of different lengths but similar cross-sections will have similar aerodynamic properties, despite large differences in mass. 

Regional deposition is dependent on the aerodynamic properties of the particles, usually described in terms of the aerodynamic particle diameter, airway dimensions, and such respiratory characteristics as flow rate, breathing frequency, and tidal volume. 

Microspheres intended for nasal administration need to be well characterized in terms of particle size distribution, since intranasal deposition of powder delivery systems is mostly determined by their aerodynamic properties and particle sizes. Commonly used methods for particle size determinations described in the literature are sieving methods [108], light microscopy [58], photon correlation spectroscopy [66], and laser diffractometry [25,41,53,93], The morphology of the microparticles (shape and surface) has been evaluated by optical, scanning, and transmission electron microscopy [66, 95],... 

The special features of the different routes of administration are dealt with in separate sections of this chapter, after a brief summary of the general properties of biological membranes and drug transport, a knowledge of which is important in understanding all absorption processes. It is impossible to be comprehensive in this one chapter, but we will concentrate on factors unique to the routes discussed, such as the properties of the vehicle in topical therapy, and the aerodynamic properties of aerosols in inhalation therapy, to give a flavour of the different problems that face formulators. Where attempts have been made to quantify absorption, equations are presented, but the derivations of most equations have been omitted. 

Chan HK, Gonda I. Aerodynamic properties of elongated particles of cromoglycic acid. J Aerosol Sci 1989, 20, 157-168. 

Grimmond, C.S.B., and Oke, T.R. (1999) Aerodynamic properties of urban areas derived from analysis of surface form, J. Appl. Meteor. 38 (9), 1262-1292. 

Mechanical filtration systems are intended to limit the introduction of pollutants from outdoors to indoors. The efficiency of such systems generally depends on the filter properties and the aerodynamic properties of filtered particles [26]. The efficiency of filters varies from 5% to 40% for low-efficiency filters, such as dry media filters, panel and bag filters, from 60% to 90% for electrostatic precipitators to over 99% for high-efficiency particulate air filters. Not only the filters, but the whole heating, ventilation and air-conditioning system contributes to particle reduction, owing to particle losses on the cooling/heating coil and other parts of the system. The selection of a system depends on the type of indoor environment, outdoor and indoor sources, the demand on the level of reduction of pollutant concentrations and the cost associated with purchase, operation and maintenance of the system. 

By the mid-1950s, General Motors had introduced fins on all their cars. The next half decade saw fins rise to even greater heights. The Chrysler imperial had exaggerated tailfins in 1955. Chrysler claimed that the fins had aerodynamic properties that improved performance. 

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