Power balance

Minimising energy consumption per ton of alurnina while maintaining a steam-power balance is an industry-wide, ongoing effort. Reduction of steam consumption has been limited by the cost of purchased power to compensate for loss of power generation. 

Figure 4-85. Power balance between string components during malfunction of bypass valve.

In a tube, the pressure is constant in all radial directions perpendicular to the axis it varies only in the flow direction x. The power balance of the element dx, denoting the sectional surface area as A and the periphery as C, gives... 

Figure 22. Returned flux at 330 nm as a function of the power balance between the two beams at 589 nm and 569 nm. Circles spectral width at L>2 = 1 GHz. Squares spectral width at L>2 = 3 GHz. Filled symbols pulse repetition rate = 4.3 kHz open symbols rep rate= 12.9 kHz.

Steam and power balances provide the link between the process utility requirements and the utility supply. The... 

In assessing the true cost benefits associated with a steam saving, the steam and power balance for the site utility system must be considered, together with the costs of fuel and power (or power credit in an export situation). In general, a surplus of steam resulting from a steam saving in a process demand can be exploited by... 

Parallel-plate electrodes CnFni in H2 and 02 to etch Si and Si02 Well mixed Mean electron density from power balance electron energy distribution from Boltzmann code 75... 

Flow between parallel-plate electrodes SFe etching silicon Plug flow Boltzmann equation and Monte Carlo for electron energy electron density power balance 77... 

Flow between parallel plate electrodes SFff-02 etching silicon Well mixed Boltzmann equation for electron energy power balance for electron density 78... 

Table 2a. Plasma parameters and power balance for a beam-driven D-T tokamak and an ignited tokamak reactor...

The plasma parameters and power balance for a beam driven D-T Tokamak and an ignited Tokamak reactor are listed in Table 2 a for illustrative purposes. The ranges of photon and particles fluxes to be expected on the first wall are listed in Table 2b. 

For the reconstruction of the size distribution, the theoretical signal course of a particle collective is calculated directly by a weighted summation of LII signals from monodisperse size classes, which are computed from the numerical solution of the power balance. The count median particle diameter dp,med, the distribution width a and the ambient temperature T0 are input parameter for this calculation. Fitting of this theoretical signal of a size-distributed particle ensemble in two different time intervals after the laser pulse ((Af)j, (Af)2) provides two characteristic signal decay times (tj = r((Af)j), r2 = t((Af)2)). 

On the other hand, medium-pressure (MP) Hg lamps can be operated with much higher electrical input power up to 30 kW, but with a reduced UV radiant power efficiency of 30 to 40%. Their dimensions are more compact than the dimensions of the LP Hg lamps, but their polychromatic emission ranges from the UV (UV-C - 15-23%, UV-B - 6-7 %, UV-A - 8%) over the VIS (-15%) to the IR (-47-55%) region of the electromagnetic spectrum (e.g. McClean, 2001). Lam-brecht (1999) reported the power balance of electromagnetic radiation of an industrially used high-pressure mercury lamp with a power density of 200 W cm as follows 13.2% UV-C, 7.15% UV-B, 7.15% UV-A, 21% VIS, and 14% IR... 

Anderson D. E., Sammis C., and Jordan T. (1971) Composition and evolution of mantle and core. Science 171, 1103. Anderson O. E. (2002) The power balance at the core-mantle boundary. Phys. Earth Planet. Inter. 131, 1-17. 

While the child will slowly acquire consciousness and capabilities to fill his own needs, the power relationship will remain very unbalanced for many years. Indeed, the power balance is much more like one we... 

Despite the fact that the test section was thermally well insulated, a power balance taking into account heat transfer with the surroundings was necessary to determine the local heat flux i x (and the local fluid temperature where x is the distance from the test section inlet. The heat flux to the fluid is... 

The temperature field can be obtained by solving a partial differential equation, the so called heat conduction equation, which will be derived now. This requires the application of the first law of thermodynamics to a closed system, namely a coherent region of any size, imaginarily taken from the conductive body, Fig. 2.1. The volume of this region is V and it has a surface area A. The first law produces the following power balance for the region ... 

Now taking the results for dU/dt from (2.4), Q from (2.6) and P from (2.7) and putting them into the power balance equation (2.2) of the first law, and combining all the volume integrals, gives... 

A power balance in the loop produced by propeller stirrer was drawn up in [297,... 

Furthermore, it is evident that the power input P0 9, particularly in the laminar range, is a multiple of that from the power balance in equation (5.35) based on equating the thrust and sinking powers. Further, the factor of 3 difference in power input between the two stirrer types should be noted, see the comments in Section... 

For a POE surfactant with a given HLB value, as the polarity of the oil phase decreases, the PIT increases. (The surfactant must be made more lipophilic to match the decreased polarity of the oil.) Thus, to keep the PIT constant (and hence a constant emulsifying power balance), the surfactant used must have a lower HLB value as the polarity of the oil phase decreases. The PIT of an emulsion made from binary mixture of oils is the weighted average, by volume, of the PITs of the emulsion made from the individual oils, using the same emulsifying agent (Arai, 1967) ... 

Furthermore, appropriate energy space averaging over Eqs. (12), derived through two-term approximation from the Boltzmann equation, yields the consistent macroscopic balance equations of the electrons. In particular, the particle and power balance can be derived from the first equation of system (12) and the momentum balance equation, normalized on the electron mass can be derived from the second equation of (12). These balance equations are... 

According to the power balance, Eq. (38), the mean power gain from the electric field is compensated for by the mean power loss in collisions, and this happens for any given gas and its specific atomic or molecular data and for any reduced field strength E/N. An analogous compensation occurs in the momentum balance, Eq. (39), between the mean momentum gain from the field and the mean momentum loss in collisions. 

Consideration of the consistent power and momentum balance, Eqs. (46) and (47), clearly shows that the establishment of the steady state simultaneously requires the complete compensation of the respective gain and loss terms and its continuation with growing time in both these balances. This means that the relaxation process and the corresponding relaxation time are mainly determined by the considerably slower establishment of the power balance. 

Consideration of Fig. 11 immediately shows that at the low field (left), after an initial relaxation phase, the mean power loss by elastic collisions P /n becomes the dominant energy loss channel. This means as was already seen from Fig. 9 (left), that the final establishment and compensation of the power balance occur only by elastic collisions in the region of low electron energies. However, as can be seen from Fig. 8, for neon, the lumped frequency v U) for energy dissipation in collisions has very small values at lower energies, which makes the large relaxation time in neon at this field strength immediately understandable. 

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