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Total dimensional analysis

There are also several possibilities for the temporal distribution of releases. Although some releases, such as those stemming from accidents, are best described as instantaneous release of a total amount of material (kg per event), most releases are described as rates kg/sec (point source), kg/sec-m (line source), kg/sec-m (area source). (Note here that a little dimensional analysis will often indicate whether a factor or constant in a fate model has been inadvertently omitted.) The patterns of rates over time can be quite diverse (see Figure 3). Many releases are more or less continuous and more or less uniform, such as stack emissions from a base-load power plant. Others are intermittent but fairly regular, or at least predictable, as when a coke oven is opened or a chemical vat... [Pg.10]

Dalton s law Dalton s law states that in a mixture of gases (A + B + C. . . ) the total pressure is simply the sum of the partial pressures (the pressures associated with each individual gas), decomposition reactions Decomposition reactions are reactions in which a compound breaks down into two or more simpler substances, diamagnetism Diamagnetism is the repulsion of a molecule from a magnetic field due to the presence of all electrons in pairs, dilute Dilute is a qualitative term that refers to a solution that has a relatively small amount of solute in comparison to the amount of solvent, dimensional analysis Dimensional analysis, sometimes called the factor label method, is a method for generating a correct setup for a mathematical problem. [Pg.360]

Naturally, the results of dimensional analysis discussed above and their consequences were not known to the ship builders of the 19th century. Since the time of Rankine, the total drag resistance of a ship has been divided into three parts the surface friction, the stern vortex and the bow wave. However, the concept of Newtonian mechanical similarity, known at that time, only stated that for mechanically similar processes the forces vary as F p l2 v2. Scale-up was not considered for assessing the effect of gravity. [Pg.38]

Buckinghams 7r-theorem [i] predicts the number of -> dimensionless parameters that are required to characterize a given physical system. A relationship between m different physical parameters (e.g., flux, - diffusion coefficient, time, concentration) can be expressed in terms of m-n dimensionless parameters (which Buckingham dubbed n groups ), where n is the total number of fundamental units (such as m, s, mol) required to express the variables. For an electrochemical system with semiinfinite linear geometry involving a diffusion coefficient (D, units cm2 s 1), flux at x = 0 (fx=o> units moles cm-2 s 1), bulk concentration (coo> units moles cm-3) and time (f, units s), m = 4 (D, fx=0, c, t) and n - 3 (cm, s, moles). Thus m-n - 1 therefore only one dimensionless parameter can be constructed and that is fx=o (t/Dy /coo. Dimensional analysis is a powerful tool for characterizing the behavior of complex physical systems and in many cases can define relationships... [Pg.60]

When Corrsin left Caltech in 1947 he was an acknowledged expert in turbulence research. This field with all its manifestations remained his primary interest throughout his career. He thereby contributed successfully to both theoretical and experimental research. He for instance familiarized with diagram techniques to clarify the sequence of nonlinear coupling terms in wave number space. His quest for clarity and precision had just one negative result He never finished the book he plaimed on fluid mechanics. His papers deal mainly with dimensional analysis, or the interpretation of the viscous terms in the turbulent energy equation. Corrsin s contribution to the Hcmdbuch proof also of his pedagogical interests, which culminated in a total of 25 PhD theses. [Pg.203]

The analysis of dimensionaUty of sections trajectory separatrix bundles shows that for splits with one distributed component trajectory of only one section in the mode of minimum reflux goes through corresponding stationary point or (there is one exception to this rule, it is discussed below). The dimensionality of bundle 5 - A4+ is equal to A - 2, that of bundle — iV+ is equal to n — A — 1. The total dimensionality is equal to n - 3. Therefore, points x/ i and Xf cannot belong simultaneously to minimum reflux bundles at any value of LlV)r. If only one of the composition points at the plate above or below the feed cross-section belongs to bundle 5 - A + and the second point belongs to bundle 5 - 5 - A+, then the total dimensionality of these bundles will become equal n - 2 therefore, such location becomes feasible at unique value oi(LjV)r (i.e., in the mode of minimum reflux). [Pg.158]

Therefore, our dimensional analysis of fluid flow through a mass of material particles or through a mass of structured solids will produce three dimensionless parameters. The Total matrix for fluid flow through a catalyst mass is... [Pg.102]

The force D) that a flowing fluid exerts upon a totally immersed body of fixed geometry, such as a sphere, will be considered next in terms of dimensional analysis. If compressibility of the fluid is ignored, the quantities of Table 6.1 suffice to define the system. [Pg.130]

This implies that the LMTD or M I D as computed in equations 20 through 26 may not be a representative temperature difference between the two heat-transferring fluids for aU tubes. The effective LMTD or M ID would be smaller than the value calculated, and consequentiy would require additional heat-transfer area. The tme value of the effective M I D may be determined by two- or three-dimensional thermal—hydrauUc analysis of the tube bundle. Baffle—Tube Support PlateXirea. The portion of a heat-transfer tube that passes through the flow baffle—tube support plates is usuaUy considered inactive from a heat-transfer standpoint. However, this inactive area must be included in the determination of the total length of the heat-transfer tube. [Pg.489]

The total phosphoms content of the sample is determined by method AOCS Ja 5-55. Analysis of phosphoUpid in lecithin concentrates (AOCS Ja 7-86) is performed by fractionation with two-dimensional thin-layer chromatography (tic) followed by acid digestion and reaction with molybdate to measure total phosphorous for each fraction at 310 nm. It is a semiquantitative method for PC, PE, PI, PA, LPC, and LPE. Method AOCS Ja 7b-91 is for the direct deterrnination of single phosphoHpids PE, PA, PI, PC in lecithin by high performance Hquid chromatography (hplc). The method is appHcable to oil-containing lecithins, deoiled lecithins, lecithin fractions, but not appHcable to lyso-PC and lyso-PE. [Pg.103]

State-of-the-art for data evaluation of complex depth profile is the use of factor analysis. The acquired data can be compiled in a two-dimensional data matrix in a manner that the n intensity values N(E) or, in the derivative mode dN( )/d , respectively, of a spectrum recorded in the ith of a total of m sputter cycles are written in the ith column of the data matrix D. For the purpose of factor analysis, it now becomes necessary that the (n X m)-dimensional data matrix D can be expressed as a product of two matrices, i. e. the (n x k)-dimensional spectrum matrix R and the (k x m)-dimensional concentration matrix C, in which R in k columns contains the spectra of k components, and C in k rows contains the concentrations of the respective m sputter cycles, i. e. ... [Pg.20]


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Dimensional analysis

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