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Balance residuals

The most probable distribution of unbalance in the finally installed rotor, considering manufacturing tolerances, balancing residuals after low-speed balance, assembly tolerances, etc. [Pg.597]

In practice, linear balances are only encountered for total mass balances. The equations for general component and energy balances are nonlinear. Consequently, Eq. (7.5), relating the balance residuals to the measurement errors, requires linearization around the approximate values e(0). For nonlinear balances, Eq. (7.7) may be further generalized as... [Pg.132]

In order to estimate the vector i in the presence of gross errors, we need to invert the covariance matrix, < , as Eq. (7.22) indicates. It is possible, though, to relate to gross errors) through the simple recursive formula (6.32), which was presented in the previous chapter. In this case we obtain the following relation ... [Pg.134]

Sip = 0 when the pth precipitate is in equilibrium with the aqueous phase if the saturation index is negative, the system is undersaturated with respect to that species, and if the index is positive, the solution is supersaturated. TTie Newton-Raphson method uses the logarithmic expressions for the saturation indexes in a similar manner to the mass balance residue expressions. [Pg.550]

The mass balance for each master species corresponds to the sum over one column of the product of the stoichiometric coefficients E) and the concentration values of the species (C). In this step, the concentrations of the precipitated species are also considered. The mass balance of protons (normally located at the first column) is exchanged with the electroneutrality condition, and then the column corresponding to the electrical charge is exchanged with the column corresponding to the protons. The mass balance residues are calculated for the Newton-Raphson method ... [Pg.551]

Figure 10J4 Temperature intervals, energy balances, residuals R, Qnmm and gcmin in kilowatts. Figure 10J4 Temperature intervals, energy balances, residuals R, Qnmm and gcmin in kilowatts.
This work investigates the use of reduced order models of reactive absorption processes. Orthogonal collocation (OC), finite difference (FD) and orthogonal collocation on finite elements (OCFE) are compared. All three methods are able to accurately describe the steady state behaviour, but they predict different dynamics. In particular, the OC dynamic models show large unrealistic oscillations. Balanced truncation, residualization and optimal Hankel singular value approximation are applied to linearized models. Results show that a combination of OCFE, linearization and balanced - residualization is efficient in terms of model size and accuracy. [Pg.929]

Fig. 4 compares the Bode diagrams of the full-order model and the models reduced to n = 10 states by different techniques. For the frequency range of interest in industrial application (10 rad / time unit, corresponding roughly to 5 rad/min), the balanced residualization offers the best approximation. [Pg.933]

For dynamic simulation, pure OC is unsuitable. OCFE is found to give realistic representation of column s behaviour, together with a small-size model. This presents a good option to FD scheme. Linear model reduction techniques are further applied to reduce the model for control design purpose. Balanced residualization with 15 states approximates satisfactorily the column dynamics. [Pg.934]

Keywords compressibility, primary-, secondary- and enhanced oil-recovery, drive mechanisms (solution gas-, gas cap-, water-drive), secondary gas cap, first production date, build-up period, plateau period, production decline, water cut, Darcy s law, recovery factor, sweep efficiency, by-passing of oil, residual oil, relative permeability, production forecasts, offtake rate, coning, cusping, horizontal wells, reservoir simulation, material balance, rate dependent processes, pre-drilling. [Pg.183]

Derivation of the working equations of upwinded schemes for heat transport in a polymeric flow is similar to the previously described weighted residual Petrov-Galerkm finite element method. In this section a basic outline of this derivation is given using a steady-state heat balance equation as an example. [Pg.91]

Design Procedure. The packed height of the tower required to reduce the concentration of the solute in the gas stream from to acceptable residual level ofjy 2 may be calculated by combining point values of the mass transfer rate and a differential material balance for the absorbed component. Referring to a sHce dh of the absorber (Fig. 5),... [Pg.25]

Additional operations essential to commercial bauxite processing are steam and power generation, heat recovery to minimise energy consumption, process liquor evaporation to maintain a water balance, impurity removal from process liquor streams, classification and washing of ttihydrate, lime caustication of sodium carbonate [497-19-8] to sodium hydroxide [1310-73-2] repair and maintenance of equipment, rehabiUtation of mine and residue disposal sites, and quaUty and process control. Each operation in the process can be carried out in a variety of ways depending upon bauxite properties and optimum economic tradeoffs. [Pg.134]

In general, rubber manufacturers balance thiol reactivity and odor. The stmcture of the thiol plays a significant role in its abiUty to be transported within the polymer matrix, particularly in emulsion polymerizations, ie, mixed water—monomer emulsion. The odor of light thiols is generally too strong for most mbber manufacturers, as it is generally hard to remove residual odors from polymers. [Pg.14]

Partially hydrolyzed poly(vinyl alcohol) grades are preferred because they have a hydrophobic /hydrophilic balance that make them uniquely suited for emulsion polymerization. The compatibUity of the residual acetate units with the poly(vinyl acetate) latex particles partly explains the observed stabilization effect. The amount of PVA employed is normally 4—10% on the weight of vinyl acetate monomer. The viscosity of the resulting latex increases with increasing molecular weight and decreasing hydrolysis of the PVA (318). [Pg.488]


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See also in sourсe #XX -- [ Pg.94 , Pg.112 ]

See also in sourсe #XX -- [ Pg.94 , Pg.112 ]




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