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Circular calculations

One could solve for t in Eq. (195) and substitute into this equation and solve for or as a practical matter simply leave it as is and make a circular calculation to solve for r ). [Pg.198]

This correction function was calculated for different kinds of excitation coils, like circular coils without ferrite core, spiral coils, double-D coils and a sheet inducer. For this purpose the eddy current density was determined for frequencies between 10 and 1000 Hz and for depths between 0 and 30 mm. [Pg.256]

We need to point out that, if the wavelengths of laser radiation are less than the size of typical structures on the optical element, the Fresnel model gives a satisfactory approximation for the diffraction of the wave on a flat optical element If we have to work with super-high resolution e-beam generators when the size of a typical structure on the element is less than the wavelengths, in principle, we need to use the Maxwell equations. Now, the calculation of direct problems of diffraction, using the Maxwell equations, are used only in cases when the element has special symmetry (for example circular symmetry). As a rule, the purpose of this calculation in this case is to define the boundary of the Fresnel model approximation. In common cases, the calculation of the diffraction using the Maxwell equation is an extremely complicated problem, even if we use a super computer. [Pg.265]

To speed up the process of attainment of the temperature steady value one can use special operations calculation without a kiln rotation, using large time intervals and calculation in two-dimensional R-tp geometry without regard for heat and mass transfer along an axis The program for realization of discussed simulation algorithms enables to calculate temperature in cells, a total number of which can not exceed 130 thousands A circular kiln structure can contain up to three layers. [Pg.421]

The resistance due to a circular junction is given by / = /2ak, where a is the radius of the junction and k is specific conductivity of the metal. For the case of two steel plates, the measured resistance is 5 x 10" Q for a load of 50 kg the yield pressure of steel is 60 kg/mm, and the specific resistance is 5x 10 Q/cm. Calculate the number of junctions, assuming that it is their combined resistance that is giving the measured value. [Pg.458]

The next question asked is whether there are any indications, from ab initio calculations, to the fact that the non-adiabatic transfonnation angles have this feature. Indeed such a study, related to the H3 system, was reported a few years ago [64]. However, it was done for circular contours with exceptionally small radii (at most a few tenths of an atomic unit). Similar studies, for circular and noncircular contours of much larger radii (sometimes up to five atomic units and more) were done for several systems showing that this feature holds for much more general situations [11,12,74]. As a result of the numerous numerical studies on this subject [11,12,64-75] the quantization of a quasi-isolated two-state non-adiabatic coupling term can be considered as established for realistic systems. [Pg.638]

In Section IV, we introduced the topological matrix D [see Eq. (38)] and showed that for a sub-Hilbert space this matrix is diagonal with (-1-1) and (—1) terms a feature that was defined as quantization of the non-adiabatic coupling matrix. If the present three-state system forms a sub-Hilbert space the resulting D matrix has to be a diagonal matrix as just mentioned. From Eq. (38) it is noticed that the D matrix is calculated along contours, F, that surround conical intersections. Our task in this section is to calculate the D matrix and we do this, again, for circular contours. [Pg.708]

At very low densities It Is quite easy Co give a theoretical description of thermal transpiration, alnce the classical theory of Knudsen screaming 9] can be extended to account for Che Influence of temperature gradients. For Isothermal flow through a straight capillary of circular cross-section, a well known calculation [9] gives the molar flux per unit cross-sectional area, N, In the form... [Pg.178]

The elements of the F matr ix depend on either the charge densities q or the bond orders p, which in turn depend on the elements of the F matrix. This circular dependence means that we must start with some initial F matrix, calculate eigenvectors, use the eigenvectors to calculate q and p, which lead to new elements in the F matr ix, calculate new eigenvectors leading to a new F matrix, and so on, until repeated iteration brings about no change in the results. The job now is to fill in the elements of the F matr ix. [Pg.250]

The convective heat-transfer coefficient and friction factor for laminar flow in noncircular ducts can be calculated from empirically or analytically determined Nusselt numbers, as given in Table 5. For turbulent flow, the circular duct data with the use of the hydrauhc diameter, defined in equation 10, may be used. [Pg.484]

Pipe-Wall Thickness. Once the design pressure and temperature have been established and the pipe material and size selected, the wall thickness is calculated using the appropriate section of the code. In rare cases, a thin pipe must be made thicker to withstand handling. Occasionally the thickness is affected by external loads or vibrations. All codes prescribe essentially the same design formula for metallic hoUow circular cylinders under internal pressure ... [Pg.58]

Drape can be measured by placing a circular fabric specimen over a round table or pedestal and viewing from direcdy overhead. A drape coefficient is defined as the ratio of the area of the fabric s actual shadow to the area of the shadow if the fabric were rigid. Drape is closely related to stiffness the drape coefficient for a stiff fabric approaches a value of 1 a limp fabric has a drape coefficient near 0. The Cusick drape tester is an example of this type of measurement. Eor this method, the relative weights of paper rings representing tracings of the fabric s shadows are used to calculate drape coefficient. [Pg.462]

The circular dichroism curves for a variety of penicillanic acid derivatives have been published and discussed (B-77MI51100) and have been used to support extended Hiickel MO calculations (77T711). [Pg.302]

Example 3 Calculation of View Factor Evaluate the view factor between two parallel circular tubes long enough compared with their diameter D or their axis-to-axis separating distance C to make the problem two-dimensional. With reference to Fig. 5-18, the crossed-strings method yields, per unit of axial length,... [Pg.575]

With the hydraulic diameter subsititued for D in/and Re, Eqs. (6-37) through (6-40) are good approximations. Note that V appearing in/and Re is the actual average velocity V = Q/A for noncircular pipes it is not ( /(7CD /4). The pressure drop should be calculated from the friction factor for uoucirciilar pipes. Eqiiations relating Q to AP and D for circular pipes may not he used for noncircular pipes with D replaced by because V Q/( KDh/4). [Pg.638]

For a short pipe of circular cross section, the conductance as calculated for an orifice from Eq. (6-82) is multiplied by a correction factor iC which may be approximated as (Kennard, Kinetic Theory of Gases, McGraw-Hill, New York, 1938, pp. 306-308)... [Pg.641]

Cascade coolers are a series of standard pipes, usually manifolded in parallel, and connected in series by vertically or horizontally oriented U-bends. Process fluid flows inside the pipe entering at the bottom and water trickles from the top downward over the external pipe surface. The water is collected from a trough under the pipe sections, cooled, and recirculated over the pipe sections. The pipe material can be any of the metallic and also glass, impeiMous graphite, and ceramics. The tubeside coefficient and pressure drop is as in any circular duct. The water coefficient (with Re number less than 2100) is calculated from the following equation by W.H. McAdams, TB. Drew, and G.S. Bays Jr., from the ASME trans. 62, 627-631 (1940). [Pg.1087]

In Ref. 2 an accurate calculation of the potential distribution is derived for rod anodes (line 3 in Table 24-1) in a uniform, circular arrangement with a radius, r. For rod anodes with grounding resistance, R, the total resistance is given by ... [Pg.545]

Square nodes in the ANFIS structure denote parameter sets of the membership functions of the TSK fuzzy system. Circular nodes are static/non-modifiable and perform operations such as product or max/min calculations. A hybrid learning rule is used to accelerate parameter adaption. This uses sequential least squares in the forward pass to identify consequent parameters, and back-propagation in the backward pass to establish the premise parameters. [Pg.362]

Circular Flanged Openings- This velocity field has a circular symmetry and it suffices to calculate the velocity directed into the opening ... [Pg.842]

IJnflanged Circular, Rectangular, and Slot Openings For unflanged openings no explicit equations exist for the flow fields. However, it is possible to calculate the velocity field outside a specific BEO using computers. These... [Pg.843]

Equations for centerline velocity outside circular, square, rectangular and slot exhausts without and with flanges are presented in Table 10.3. These equations have been chosen to have as large an application as possible. For very detailed calculations it is recommended that the original research references be consulted. 09,40... [Pg.844]

The same basic procedures as described above can be used if the source and hood are rectangular rather than circular. The two dimensions of the plume and hood must be calculated independently by substituting them for d, in the equations developed above. [Pg.872]

However, one should be cautious when comparing the Reynolds number from regular Karman vortex streets with the Reynolds number calculated from factual situations in clean benches as the airflow from behind an obstacle is usually not the typically formed Karman vortex street predicted for an indefinitely long circular cylinder. The wake situations during actual conditions often seem to have a three-dimensional stmcnire. [Pg.931]

Figure 3-32 Halpin-Tsai Calculations (Circles) versus Adams and Doner s Calculations for E2 of Circular Fibers in a Square Array (After Halplrt ar d Tsai [3-17])... Figure 3-32 Halpin-Tsai Calculations (Circles) versus Adams and Doner s Calculations for E2 of Circular Fibers in a Square Array (After Halplrt ar d Tsai [3-17])...

See other pages where Circular calculations is mentioned: [Pg.277]    [Pg.361]    [Pg.277]    [Pg.361]    [Pg.256]    [Pg.257]    [Pg.5]    [Pg.1309]    [Pg.5]    [Pg.157]    [Pg.182]    [Pg.174]    [Pg.145]    [Pg.250]    [Pg.250]    [Pg.27]    [Pg.831]    [Pg.674]    [Pg.27]    [Pg.58]    [Pg.316]    [Pg.426]    [Pg.265]    [Pg.167]    [Pg.844]    [Pg.152]   
See also in sourсe #XX -- [ Pg.270 ]




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