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Transient Analysis final time

Click the OK button and then run the simulation. It will take three times as long as the previous simulation because the Transient Analysis will run three times. Logically, the Transient Analysis runs inside the Temperature Sweep. For this example, the temperature will be set to -25°C, and then the Transient Analysis will be run. Next, the temperature will be set to 25°C, and then the Transient Analysis will be run. Finally, the temperature will be set to 125°C, and then the Transient Analysis will be run. [Pg.409]

The first line of any SPICE netlist is the title line. It is used for documentation purposes only. The next few lines usually tell SPICE which analysis will be performed and what the bounds of that analysis will be. For example, we may be requesting a time domain analysis of a circuit (called a transient analysis). The information as to how long the waveform is and what increments and what section of it are of interest is defined in this section of the code. SPICE netlists generally have one function, command, or element per line (Fig. 2.1). Also defined upfront are global constants, subcircuits (models) used repeatedly in the main circuit, and instructions on which nodes are of interest in the final solution, though this structure is not mandatory. [Pg.10]

It is required to provide a suitable pressure relief device. If the transient analysis indicates an instantaneous increase in pressure, up to the PSV relief pressure, a rupture disk is needed to protect the system (because the PSV response time is much slower). However, the disadvantages of a rupture disk should also be considered before finalizing the type of protection required. [Pg.299]

Finally, transient absorption measurements were deemed necessary to confirm the photoproducts in 21a,b and 22a,b. Due to overlapping absorptions of Cso, oFL and ZnP, which would impede a clear analysis, we have focused first on the selective excitation of ZnP. To this end, transient absorption spectra of the reference compounds (19 and 20a,b) reveal the instantaneous formation of the ZnP singlet excited state with maxima at 460 and 800 nm and minima at 565 and 605 nm. Furthermore, an isosbestic point at 500 nm as it develops on a time scale of 3000 ps reflects the intersystem crossing process at which end the triplet excited state of ZnP stands. The latter includes maxima at 530, 580 and 640 nm (Fig. 9.57a). Equally important is the fact that the decay of the singlet excited state matches the formation of the triplet excited state kinetics (Fig. 9.57b). [Pg.161]

We start this chapter with the analysis of lumped systems in which the temperature of a body varies with time but remains uniform throughout at any time. Then we consider the variation of temperature with time as well as position for one-dimensional heat conduction problems such as those associated with a large plane wall, a long cylinder, a sphere, and a semi infinite medium using transient temperature charts and analytical solutions. Finally, we consider transient heat conduction in multidimensional systems by utilizing the product solution. [Pg.236]

The transient behavior of a continuous countercurrent multicomponent system was considered in detail by Rhee, Aris and Amimdson [22,23] from the perspective of the equilibrium theory, i.e., assuming that axial dispersion and the mass transfer resistances are negligible and that equilibrium is established everywhere, at every time along the colinnn. The final steady-state predicted by the equilibrium theory is simply a uniform concentration throughout the colimm, with a transition at one end or the other. Therefore, the equilibriinn theory analysis is of lesser practical value for a coimtercurrent system, which normally operates rmder steady-state conditions, than for a fixed-bed (i.e., an SMB) system, which normally operates under transient conditions. The equilibrium theory analysis, however, reveals that, under different experimental conditions, several different steady-states are possible in a coimtercurrent system. It shows how the evolution of the concentration profiles may be predicted in order to determine which state is obtained in a particular case. [Pg.816]

An analysis of the equation of motion for a single transient bubble under a constant driving sound pressure can be performed by solving the Kirkwood-Bethe-Gilmore model. The best combination of sound pressure and initial bubble radius can be found by demanding a maximum bubble radius prior to collapse, a very small final radius and a collapse that is timed to be finished at the maximum positive pressure. [Pg.198]

The acquisition of a single-wavelength fluorescence spectrum of a complex multicomponent mixture is more tedious for many analytical applications that involve the measurement of some essential intermediate components or transient species. The determinations of such systems become more critical if the spectral information for those species is important to the understanding and elucidation of the properties of the final product. Similarly, this is true for chemical measurements of components whose fluorescence intensity decreases continuously with time. A rapid multidimensional data-processing technique becomes exceedingly important in the analysis of these species in a chemical reaction. [Pg.1347]

The predictor/corrector algorithm in Diva includes a stepsize control in order to minimize the number of predictor and corrector steps. Finally, the continuation package contains methods for the computation of the dominating eigenvalues of DAEs. This allows a stability analysis of the steady state solutions and a detection of local bifurcations for large sparse systems. As the continuation method is embedded into a dynamic simulator, the user has the opportunity to switch interactively from continuation to time integration. This allows additional investigations of transient behaviour or domains of attraction with the same simulation tool[2]. [Pg.151]

As shown in Table 4.2, large break LOCA events involve the most physical phenomena and, therefore, require the most extensive analysis methods and tools. Typically, 3D reactor space-time kinetics physics calculation of the power transient is coupled with a system thermal hydraulics code to predict the response of the heat transport circuit, individual channel thermal-hydraulic behavior, and the transient power distribution in the fuel. Detailed analysis of fuel channel behavior is required to characterize fuel heat-up, thermochemical heat generation and hydrogen production, and possible pressure tube deformation by thermal creep strain mechanisms. Pressure tubes can deform into contact with the calandria tubes, in which case the heat transfer from the outside of the calandria tube is of interest. This analysis requires a calculation of moderator circulation and local temperatures, which are obtained from computational fluid dynamics (CFD) codes. A further level of analysis detail provides estimates of fuel sheath temperatures, fuel failures, and fission product releases. These are inputs to containment, thermal-hydraulic, and related fission product transport calculations to determine how much activity leaks outside containment. Finally, the dispersion and dilution of this material before it reaches the public is evaluated by an atmospheric dispersion/public dose calculation. The public dose is the end point of the calculation. [Pg.187]

ABSTRACT. Several aspects of electrochemistry at ultramicroelectrodes are presented and discussed in relevance to their application to the analysis of chemical reactivity. The limits of fast scan cyclic voltammetry are examined, and the method shown to allow kinetic investigations in the nanosecond time scale. On the other hand, the dual nature of steady state at ultramicroelectrodes is explained, and it is shown how steady state currents may be used, in combination with transient chronoamperometry, for the determination of absolute electron stoichiometries in voltammetric methods. Finally the interest of electrochemistry in highly resistive conditions for discussion and investigation of chemical reactivity is presented. [Pg.625]


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See also in sourсe #XX -- [ Pg.336 , Pg.351 ]




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