Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Reservoirs coupled

As important as coupled reservoirs and nonlinear systems are, the less mathematically inclined may want to read this section only for [Pg.67]

A linear system of reservoirs is one where the fluxes between the reservoirs are linearly related to the reservoir contents. A special case, that is commonly assumed to apply, is one where the fluxes between reservoirs are proportional to the content of the reservoirs where they originate. Under this proportionality assumption the flux f,y from reservoir i to reservoir j is given by [Pg.68]

This system of differential equations can be written in matrix form as [Pg.68]

As an illustration of the concept introduced above, let us consider a coupled two-reservoir system with no external forcing (Fig. 4-6). The dynamic behavior of this system is governed by the two differential equations [Pg.68]

It is seen that in the steady state the total mass is distributed between the two reservoirs in proportion to the sink coefficients (in reverse proportion to the turnover times), independent of the initial distribution. [Pg.69]

The treatment of time-scales and dynamic behavior of single reservoirs given in the previous section can easily be generalized to systems of two or more reservoirs. While the simple system analyzed in the previous section illustrates many important characteristics of cycles, most natural cycles are more complex. The matrix method described in Section [Pg.61]


Fig. 4-7 Example of a coupled reservoir system where the steady-state distribution of mass is not uniquely determined by the parameters describing the fluxes within the system but also by the initial conditions (see text). Fig. 4-7 Example of a coupled reservoir system where the steady-state distribution of mass is not uniquely determined by the parameters describing the fluxes within the system but also by the initial conditions (see text).
Rutqvist J., Vasco D.W., et al. Coupled reservoir-geochemical analysis of C02 injection at In Salah, Algeria. 2009 Energy Procedia 1 1847-1854. [Pg.177]

This chapter demonstrated the computational simplification that is possible in systems consisting of a one-dimensional chain of coupled reservoirs, which arise in diffusion and heat conduction problems. In such systems each equation is coupled just to its immediate neighbors, so that much of the work involved in Gaussian elimination and back substitution can be avoided. I presented here two subroutines, GAUSSD and SLOPERD, that deal efficiently with this kind of system. [Pg.148]

Navarro E, Bacardit M, Caputo L, Palau T, Armengol J (2006) Limnological characterization and flow patterns of a three-coupled reservoir system and their influence on Dreissena polymorpha populations and settlement during the stratification period. Lake Reservoir Manage 22 293-302... [Pg.94]

As important as coupled reservoirs and non-linear systems are, the less mathematically inclined may want to read this section only for its qualitative material. The treatment described here is not essential for understanding the reading later in the book. [Pg.61]

In many cases faults will only restrict fluid flow, or they may be open i.e. non-sealing. Despite considerable efforts to predict the probability of fault sealing potential, a reliable method to do so has not yet emerged. Fault seal modelling is further complicated by the fact that some faults may leak fluids or pressures at a very small rate, thus effectively acting as seal on a production time scale of only a couple of years. As a result, the simulation of reservoir behaviour in densely faulted fields is difficult and predictions should be regarded as crude approximations only. [Pg.84]

Another development arising from FAB has been its transformation from a static to a dynamic technique, with a continuous flow of a solution traveling from a reservoir through a capillary to the probe tip. Samples are injected either directly or through a liquid chromatography (LC) column. The technique is known as dynamic or continuous flow FAB/LSIMS and provides a convenient direct LC/MS coupling for the on-line analysis of mixtures (Figure 40.2). [Pg.288]

Eig. 2. Cychc steam stimulation of an oil well (a) steam, injected into a well over a period of days or weeks in a heavy oil reservoir, introduces heat (huff) that, coupled with (b), alternate soak periods lasting a few days to allow (c) a production phase of weeks or months (puff), thins the oil. This process may... [Pg.190]

In this work ion-exchange and gel-permeation chromatography coupled with membrane filtration, photochemical oxidation of organic metal complexes and CL detection were applied to the study of the speciation of cobalt, copper, iron and vanadium in water from the Dnieper reservoirs and some rivers of Ukraine. The role of various groups of organic matters in the complexation of metals is established. [Pg.174]

The main problem of elementary chemical reaction dynamics is to find the rate constant of the transition in the reaction complex interacting with its environment. This problem, in principle, is close to the general problem of statistical mechanics of irreversible processes (see, e.g., Blum [1981], Kubo et al. [1985]) about the relaxation of initially nonequilibrium state of a particle in the presence of a reservoir (heat bath). If the particle is coupled to the reservoir weakly enough, then the properties of the latter are fully determined by the spectral characteristics of its susceptibility coefficients. [Pg.7]

Moreover, in this linear-response (weak-coupling) limit any reservoir may be thought of as an infinite number of oscillators qj with an appropriately chosen spectral density, each coupled linearly in qj to the particle coordinates. The coordinates qj may not have a direct physical sense they may be just unobservable variables whose role is to provide the correct response properties of the reservoir. In a chemical reaction the role of a particle is played by the reaction complex, which itself includes many degrees of freedom. Therefore the separation of reservoir and particle does not suffice to make the problem manageable, and a subsequent reduction of the internal degrees of freedom in the reaction complex is required. The possible ways to arrive at such a reduction are summarized in table 1. [Pg.7]

The intrinsic drawback of LIBS is a short duration (less than a few hundreds microseconds) and strongly non-stationary conditions of a laser plume. Much higher sensitivity has been realized by transport of the ablated material into secondary atomic reservoirs such as a microwave-induced plasma (MIP) or an inductively coupled plasma (ICP). Owing to the much longer residence time of ablated atoms and ions in a stationary MIP (typically several ms compared with at most a hundred microseconds in a laser plume) and because of additional excitation of the radiating upper levels in the low pressure plasma, the line intensities of atoms and ions are greatly enhanced. Because of these factors the DLs of LA-MIP have been improved by one to two orders of magnitude compared with LIBS. [Pg.234]

The safety valve is normally situated atop the air reservoir. There must be no restriction on all blow-off points. Compressors can be hazardous to work around because they do have moving parts. Ensure that clothing is kept away from belt drives, couplings and exposed shafts. [Pg.647]

Unlike conventional Metropolis-like Monte Carlo simulations where an effective temperature is defined by coupling the system to some thermal reservoir, here the temperature is a purely statistical parameter that is deduced fiom the observed demon energy ... [Pg.362]

The I9e electron-reservoir complexes Fe Cp(arene) can give an electron to a large number of substrates and several such cases have been used for activation. After ET, the [FenCp(arene)]+ cation left has 18 valence electrons and thus cannot react in a radical-type way in the cage as was the case for 20e Fe°(arene)2 species. Thus the 19e Fe Cp(arene) complexes react with the organic halide RX to give the coupled product and the [FeCp(arene)]+ cation. Only half of the starting complex is used e.g., the theoretical yield is limited to 50% [48] (Scheme VI) contrary to the reaction with Fe°(arene)2 above. [Pg.59]

The special salt effect is a constant feature of the activation of substrates in cages subsequent to ET from electron-reservoir complexes. In the present case, the salt effect inhibits the C-H activation process [59], but in other cases, the result of the special effect can be favorable. For instance, when the reduction of a substrate is expected, one wishes to avoid the cage reaction with the sandwich. An example is the reduction of alkynes and of aldehydes or ketones [60], These reductions follow a pathway which is comparable to the one observed in the reaction with 02. In the absence of Na + PFg, coupling of the substrate with the sandwich is observed. Thus one equiv. Na+PFg is used to avoid this cage coupling and, in the presence of ethanol as a proton donor, hydrogenation is obtained (Scheme VII). [Pg.61]

In situations where Tobs is comparable in magnitude to tq, a more complex relation prevails between Q, S, and M. Atmospheric CO2 falls in this last category although its turnover time (3 years, cf. Fig. 4-3) is much shorter than Tobs (about 300 years). This is because the atmospheric CO2 reservoir is closely coupled to the carbon reservoir in the biota and in the surface layer of the oceans (Section 4.3). The effective turnover time of the combined system is actually several hundred years (Rodhe and Bjdrk-strom, 1979). [Pg.67]

Fig. 4-6 A coupled two-reservoir system with fluxes proportional to the content of the emitting reservoirs. Fig. 4-6 A coupled two-reservoir system with fluxes proportional to the content of the emitting reservoirs.

See other pages where Reservoirs coupled is mentioned: [Pg.67]    [Pg.16]    [Pg.61]    [Pg.135]    [Pg.628]    [Pg.128]    [Pg.590]    [Pg.67]    [Pg.16]    [Pg.61]    [Pg.135]    [Pg.628]    [Pg.128]    [Pg.590]    [Pg.465]    [Pg.176]    [Pg.199]    [Pg.200]    [Pg.233]    [Pg.2536]    [Pg.310]    [Pg.200]    [Pg.200]    [Pg.116]    [Pg.124]    [Pg.553]    [Pg.899]    [Pg.9]   
See also in sourсe #XX -- [ Pg.67 , Pg.68 , Pg.69 , Pg.70 , Pg.71 , Pg.72 ]

See also in sourсe #XX -- [ Pg.61 ]




SEARCH



Non-linear coupling of geochemical reservoirs

Reservoir Species and Coupling of the Cycles

© 2024 chempedia.info