Big Chemical Encyclopedia

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

Articles Figures Tables About

Steady states three-dimensional

Detonation Waves, Cylindrically Symmetric Flow Within the Steady Zone in. See under Detonation Waves Steady-State, Three-Dimensional, Axially Symmetric with Finite Reaction Rate... [Pg.684]

DETONATION WAVES STEADY-STATE, THREE-DIMENSIONAL, AXIALLY SYMMETRIC, WITH FINIT E REACTION RATE... [Pg.710]

Detonation wave, steady state, three-dimensional, axially symmetric with finite reaction rate 4D710... [Pg.544]

Deriving the axisymmetric stagnation-flow equations begins with the steady-state three-dimensional Navier-Stokes equations (Eqs. 3.58, 3.60, and 3.60), but considering flow only in the z-r plane. In general, there may be a circumferential velocity component ui, but there cannot be variations of any variable in the circumferential direction 0. The derivation depends on two principal conjectures. First, the velocity field is presumed to be described in terms of a streamfunction that has the separable form... [Pg.252]

The flow of heat and momentum in the electric furnace was assumed to occur under steady state conditions, so that only steady-state solutions were sought. Further, the flow was mainly laminar, but where it was turbulent the conventional k-e model (9) was applied. Hence, the steady-state transport equations for momentum and heat were solved in three dimensions. The generalized steady-state three-dimensional equation for a conserved variable, q>, is ... [Pg.695]

Wambersie, O. and M. J. Crochet, Transient finite element method for calculating steady state three-dimensional free surfaces, Int. J. Num. Meth. Fluids 14 545-360 (1992). [Pg.365]

In reality, heat is conducted in all three spatial dimensions. While specific building simulation codes can model the transient and steady-state two-dimensional temperature distribution in building structures using finite-difference or finite-elements methods, conduction is normally modeled one-... [Pg.1066]

After confirming that the flow state in a circular pipe becomes steady, the three-dimensional movement of water, which is represented by the movement of the tracer particles, is measured by recording their movement on video. The local mixing capacity M0 and MI based on the outflow and inflow, respectively, of each radial region as the distributor and blender, respectively, is calculated by using Eq. (2.27). [Pg.65]

Stable flow with strong vortex growth [31]. Obviously, any steady-state, two-dimensional, axisymmetric simulations are incapable of reproducing three-dimensional, time-dependent effects, such as the pulsating flow patterns exhibited by some polymer solutions in contractions. [Pg.149]

Models which assume uniform mixing throughout the volume of a three-dimensional box are useful for estimating concentrations, especially for first approximations. For steady-state emission and atmospheric conditions, with no upwind background concentrations, the concentration is given by... [Pg.324]

In the simplest case of one-dimensional steady flow in the x direction, there is a parallel between Eourier s law for heat flowrate and Ohm s law for charge flowrate (i.e., electrical current). Eor three-dimensional steady-state, potential and temperature distributions are both governed by Laplace s equation. The right-hand terms in Poisson s equation are (.Qy/e) = (volumetric charge density/permittivity) and (Qp // ) = (volumetric heat generation rate/thermal conductivity). The respective units of these terms are (V m ) and (K m ). Representations of isopotential and isothermal surfaces are known respectively as potential or temperature fields. Lines of constant potential gradient ( electric field lines ) normal to isopotential surfaces are similar to lines of constant temperature gradient ( lines of flow ) normal to... [Pg.2]

A young scientist said, I have never seen a complex scientific area such as industrial ventilation, where so little scientific research and brain power has been applied. This is one of the major reasons activities in the industrial ventilation field at the global level were started. The young scientist was right. The challenges faced by designers and practitioners in the industrial ventilation field, compared to comfort ventilation, are much more complex. In industrial ventilation, it is essential to have an in-depth knowledge of modern computational fluid dynamics (CFD), three-dimensional heat flow, complex fluid flows, steady state and transient conditions, operator issues, contaminants inside and outside the facility, etc. [Pg.1]

The three-diiuensional and dynamic CFD computations show a strong imer-mittenr behavior ol the cold-air downdrafts. Two-dimensional and steady-state models produce results which rarely reflect the real situation. [Pg.1103]

A more rigorous treatment takes into account the hydrodynamic characteristics of the flowing solution. Expressions for the limiting currents (under steady-state conditions) have been derived for various electrodes geometries by solving the three-dimensional convective diffusion equation ... [Pg.91]

Fig. 10.10 Three-dimensional diagram of steady states I and HI are domains of existence of single solution, II is a domain of existence of three solutions (two stable and one unstable). Boundary surfaces correspond to two stable solutions. Reprinted from Yarin et al. (2002) with permission... Fig. 10.10 Three-dimensional diagram of steady states I and HI are domains of existence of single solution, II is a domain of existence of three solutions (two stable and one unstable). Boundary surfaces correspond to two stable solutions. Reprinted from Yarin et al. (2002) with permission...
Unlike the case of a surface reaction, there is no need to specify the units of measurement because all reacting species are in the three-dimensional space of the reaction medium, and all relevant rates are in concentration per unit of time. The unknown concentration of the unoccupied enzymes follows by assuming that the reaction is at steady state ... [Pg.75]

Note that because momentum is a vector, this equation represents three component equations, one for each direction in three-dimensional space. If there is only one entering and one leaving stream, then = m0 = m. If the system is also at steady state, the momentum balance becomes... [Pg.121]

The UMEs used in bioarrays can be divided into three types disk, ring, and strip electrodes. The theory of the disk, ring, and strip UMEs has been extensively studied [97-100], Due to the edge effect, the profile of the mass diffusion to the ultramicroelectrode surface is three dimensional, and can significantly enhance the mass transportation in comparison to the conventional large electrode with one-dimensional mass transportation. The steady-state measurement at a planar UME can be expressed as... [Pg.371]

The conservation equations described in Section B.l show the mass, momentum, energy, and chemical species equations at a steady state in a one-dimensional flow field. Similarly, the conservation equations at a steady-state in two- or three-dimensional flow fields can be obtained. The results can be summarized in a vector form... [Pg.475]

Lack of steady flow of a liquid-bearing colloidal solution requires the existence of a space-filling, three-dimensional structure. As we might select a perfect crystal as a csuionical solid, or liquid argon as a prototypical liquid, we csui choose the covalently crosslinked network, without any entanglements, to represent the ideal gel state. Then an appropriate time scale for reversible gels would be the lifetime of a typical crosslink bond if subjected to conditions that would cause flow in a pure... [Pg.4]

For steady-state solution, the initial condition does not matter because the steady state does not depend on the initial condition. Only the boundary condition is necessary for solving the steady-state diffusion equation. The three-dimensional diffusion equation at steady state is... [Pg.192]

Now consider the case of three-dimensional crystal dissolution. Let the radius of the crystal be a (which depends on time). In this case, the most often-used reference frame is fixed at the center of the crystal, i.e., lab-fixed reference frame (different from the case of one-dimensional crystal growth for which the reference frame is fixed at the interface) so that the problem has spherical symmetry. Ignore melt density variation. The crystal dissolution rate (u ) and melt growth rate at the interface (Ua) are related by the continuity equation with approximation of steady state ... [Pg.377]

Leucophane is a relatively rare berylhum silicate. Of interest are the trace amounts of rare earth elements in its chemistry, especially cerium which substitutes for some calcium. Its true symmetry is triclinic, pedion class which is the lowest symmetry possible in a three dimensional system. The only symmetry element is translational shift as it lacks any mirrors, rotations, or even a center. The symmetry is noted by a 1. Ce ", Eu +, Sm +, Dy +, Tb ", Nd " " and Mn " centers characterize steady-state luminescence spectra of leucophane (Gorobets and Rogojine 2001). Time-resolved luminescence spectra contain additionally Eu and Tm " " centers (Fig. 4.25). [Pg.71]


See other pages where Steady states three-dimensional is mentioned: [Pg.358]    [Pg.588]    [Pg.876]    [Pg.945]    [Pg.62]    [Pg.334]    [Pg.542]    [Pg.358]    [Pg.588]    [Pg.876]    [Pg.945]    [Pg.62]    [Pg.334]    [Pg.542]    [Pg.177]    [Pg.43]    [Pg.17]    [Pg.17]    [Pg.644]    [Pg.353]    [Pg.289]    [Pg.35]    [Pg.347]    [Pg.274]    [Pg.265]    [Pg.266]    [Pg.331]    [Pg.268]    [Pg.338]    [Pg.501]   


SEARCH



Steady-State, Three-Dimensional, Axially Symmetric with

Three-state

© 2024 chempedia.info