Similarity law

DOL). Similar laws are in place in almost every country in the world and are proposed by such international organizations as the World Health Organization (WHO) and the International Labor Organization (ILO). 

The future use of lead may be decided by the resolution of an environmental paradox. Some markets for lead are being phased out because of environmental concerns, eg, the use of tetraethyllead as a gasoline additive. However, a 1990 State of California law and similar laws in nine eastern U.S. states require that 2% of new cars meet 2ero-emission standards in 1998. By 2003 this requirement rises to 10% of new vehicles. Zero emission vehicles are generally accepted to mean electric, ie, battery powered cars, and there is considerable research effort to bring suitable electric vehicles to market by 1998. 

Film growth (and its cathodic dissolution) is controlled by similar laws as... 

Experience under the German law and similar laws in other countries indicates that such laws are workable, but the cost of administering them is substantial. Neither employed inventors nor employers are completely satisfied with them. 

The similarity laws summarized by Equation 18 may be useful, in conjunction with experimental measurements of temperatures and flow velocities, for determining (over-all) composition changes during flow for complex chemical reactions described by an effective, one-step, overall process. Needless to say, however, the similarity relations are no substitute for the solution of kinetic equations. Rather, the use of similarity principles is complementary to the use of kinetic equations since it serves to uncouple the energy and species conservation equations from each other. As has been emphasized before (15) for a one-step reaction, we must solve one kinetic equation of the form,... 

Court decisions have upheld the Maine price controls, and several states have adopted similar laws. 

In the second paper (5) Ya.B. obtained the now classical similarity laws of ascending convective flow development (for both laminar and turbulent flows). These laws are now widely used by geophysicists in studies of atmospheric and oceanic convection. In 1953-1954 A. S. Monin and A. M. Obukhov independently used the same fruitful ideas for other conditions and obtained similarity laws for shear flow in a density stratified medium in a gravity field. 

The fundamental self-similarity laws of the evolution of freely-ascending laminar and turbulent convective flows have found numerous applications, above all in geophysics. 

Laws were found for the combustion of gases in laminar or turbulent flow. Similarity laws were formulated for flame propagation under conditions in which the difference in density of a substance before and after combustion causes convective motion of the gas and flame.1... 

As a result of those laws and regulations, and similar laws in other nations, a black market for amphetamines emerged in many countries. In the 1990s, illicit amphetamine production was increasingly reported in the western United States and eastern Europe, particularly in Poland and Hungary. 

Thus, the similarity laws enable us to make experiments with a convenient fluid—such as water, for example—and then apply the results to a fluid which is less convenient to work with, such as air, gas, steam, or oil. Also, in both hydraulics and aeronautics valuable results can be obtained at a minimum cost by tests made with small-scale models of the full-size apparatus. The laws of similitude make it possible to determine the performance of the full-size prototype, from tests made with the model. It is not necessary that the same fluid be used for the model and its prototype. Neither is the model necessarily smaller than its prototype. Thus, the flow in a carburetor might be studied in a very large model. And the flow of water at the entrance to a small centrifugal-pump runner might be investigated by the flow of air at the entrance to a large model of the runner. 

The similar law is for the concentration dependence of the correlation length of the percolation cluster (that is the size at which a self-crossing of current paths occurs or the effective radius of the percolation net) ... 

Subsequently France, the Netherlands and Belgium also issued similar laws, although each provision differed from the other not so much in the objectives behind them (consumer protection) as in the ways of achieving those objectives. 

The Meat Inspection Act of 1906. The responsibility for the safety and wholesomeness of meat and meat products falling under the provisions of this act is delegated to the U.S. Department of Agriculture (USDA). The USDA s responsibilities include inspection of meatprocessing facilities and animals before and after slaughter, inspection of meat products and meat-processing laboratories, and premarket clearance of meat product labels. When a food product contains less than 3 percent meat, the product comes under the jurisdiction of the FDA. Similar laws are the Poultry Products Inspection Act and the Egg... 

Related Calculations. Use the similarity laws to extend or change the data obtained from centrifugal-pump characteristic curves. These laws are also useful in field calculations when the pump head, capacity, speed, or impeller diameter is changed. 

The similarity laws are most accurate when the efficiency of the pump remains nearly constant. Results obtained when the laws are applied to a pump having a constant impeller diameter are somewhat more accurate than for a pump at constant speed with a changed impeller diameter. The latter laws are more accurate when applied to pumps having a low specific speed. 

If the similarity laws are applied to a pump whose impeller diameter is increased, be certain to consider the effect of the higher velocity in the pump suction line. Use the similarity laws for any liquid whose viscosity remains constant during passage through the pump. However, the accuracy of the similarity laws decreases as the liquid viscosity increases. 

For the model, Ns = 3500(500)as/350a75 = 965 S = 3500(500)°-5/10°-75 = 13,900. For the prototype, Ns = 1170(1158)a5/142.5a75 = 965 5 = 1170(1156)a5/4.06a75 = 13,900. The specific speed and suction specific speed of the model and prototype are equal because these units are geometrically similar or homologous pumps and both speeds are mathematically derived from the similarity laws. 

Related Calculations. Use the procedure given here for any type of centrifugal pump where the similarity laws apply. When the term model is used, it can apply to a production test pump or to a standard unit ready for installation. The procedure presented here is the work of R. P. Horwitz, as reported in Power magazine [2]. 

The power (P is the power given to the fluid. In plots of characteristic curves such as Figure 4.8, however, the brake power is the one plotted. Becanse bears a ratio to that of the brake power in the form of the efficiency t], the similarity laws that we have developed also apply to the brake power, and figures such Figure 4.8 may be used for scaling brake powers of pumps. 

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