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Vertical boundary

Sealing. Approved seals shall be provided in accordance with Section 501-5. Sealing requirements in Sections 501-5(a) (4) and (b) (2) shall apply to horizontal as well as to vertical boundaries of the defined Class 1 locations. Buried raceways under defined Class 1 locations shall be considered to be within a Class 1, Division 1 location. [Pg.645]

We then consider a model problem of bouyancy recirculation in a closed cavity, using the same mesh of the previous example. Here the vertical boundaries are held at fixed temperatures, the left hotter than the right, while the horizontal boundaries are left unconstrained. A linear temperature gradient is thus set up between the left and right boundaries. The cooler and denser fluid at the right will tend to move down and displace the warm fluid at the left, setting up a clockwise circulation as seen in the streamline contour plot of Figure 6. [Pg.276]

As before, is determined from the vertical boundary conditions. If the source is at height h and the only barrier to diffusion is the ground,... [Pg.246]

To implement the method, it is necessary to decide how to handle the case when a particle encounters either vertical boundary. Following Fig. 11, if a particle is predicted to cross the boundary, its position can be reflected. At the next step, n + 1 to n + 2, the velocity at step n + 1 can be taken as the reflected value (line a in Fig. 11), as the previous value unreflected (line b), or as zero with only the random component (case c). In Fig. 12, dimensionless surface concentrations are shown corresponding to each of these three options. As expected, the lowest concentrations... [Pg.292]

Fig. 5 a-d. Representation of DSC temperature scan for an exothermic reaction, showing baseline construction a) horizontal b) linear c) proportional and d) linear with vertical boundary... [Pg.117]

In this case a second DSC scan on the reacted sample may indicate an open-ended peak as in Fig. 5d and a horizontal baseline with an interpolated vertical boundary can be used as an approximation. [Pg.117]

The step-wise model describes the rise of three successive plateaus along discrete vertical boundaries separated in time by tens of millions of years. Attainment of elevation occurs episodically and progresses away from the collision zone at distinct time intervals that are coeval with periods of upper crustal shortening, magmatism related to mantle lithosphere subduction, and high erosion rates that produce sediment and basin infilling to subdue relief (Fig. 2A). [Pg.7]

Batchelor, G.K., Heat Transfer by Free Convection Across a Closed Cavity between Vertical Boundaries at Different Temperatures , / AppL Math, Vol. 12, pp. 209-233, 1954. [Pg.422]

Bejan, A. and Poulikakos. D.. The NonDarcy Regime for Vertical Boundary Layer Natural Convection in a Porous Medium , Int. J. Heat Mass Transfer, Vol. 27, pp. 717-722, 1984. [Pg.553]

The diagram s vertical boundaries (Fig. 15, number 1-5) are reactions that describe a dissolution in water (hydrolysis) independent of the EH value. The boundaries of the respective predominance fields are calculated via the equilibrium constants for the conversion of the species at each side of the boundary line into each other. [Pg.42]

Within this framework, one can imagine a two dimensional ductile-brittle transition criterion which would be composed of two perpendicular boundaries in the graph la-Mw (Fig. 7). The vertical boundary would correspond to a critical molar mass M c- In polymers of low crystallinity or fully amorphous, M c would be sharply linked to the entanglement molar mass M c 5Me. In polymers of medium to high crystallinity, M c would be the molar mass below which it is impossible to have values higher than lac- The horizontal boundary would correspond to U = lac-... [Pg.169]

There is a fundamental objection to the use of the boxmdary conditions described above. These conditions have vertical boundaries or shocks (Chapter 7) at both... [Pg.33]

Here it is the vector of the horizontal velocity, U the vertically integrated horizontal velocity, w is the vertical velocity, r is the sea-level elevation, V/, the horizontal nabla operator, q a source term of water flux, T the temperature, S the salinity, p the pressure, and p is the density. Moreover,/is the inertial frequency,/= 2 1 sin 0, where 1 Zn (1 I 1/365.2425)724 h is the earth s angular velocity and 0 is the latitude. Turbulent viscosity is indicated by the term D, . Wind forcing enters the scheme as a vertical boundary condition. The equations are solved usually in spherical coordinates, but are written here for simplicity in Cartesian form. [Pg.586]

The next step in the procedure is to formulate mass and momentum balances for an element of the boundary layer, as sketched in Fig 5.18. The mass balance equates the net rate of mass flow across the two vertical boundaries to the rate of mass flow across the horizontal boundaries. Assuming no mass flow across the lower horizontal boundary, the mass balance becomes ... [Pg.620]

The governing equations are elliptic so boundary conditions are required at all boundaries. The normal velocity components for both phases are set to zero at the vertical boundaries. The wall boundary conditions for the vertical velocity component, k and e are specified in accordance with the standard wall function approach. The particle phase is allowed to slip along the wall following the boundary condition given by (4.99). [Pg.934]

Consider a heated vertical plate in a quiescent fluid. The plate heats the fluid in its neighborhood, which then becomes lighter and moves upward. The force resulting from the product of gravity and density difference and causing this upward motion is called buoyancy. The fluid moving under the effect of buoyancy develops a vertical boundary layer about the plate. Within the boundary layer the temperature decreases from the plate temperature to the fluid temperature, while the velocity vanishes on the plate walls and beyond the boundary layer and has a maximum in between (Fig. 5.13). Actually, in a manner similar to forced convection, the momentum boundary layer of natural convection is expected to be thicker for larger Prandtl numbers than the thermal boundary layer. However, the characteristic velocity for the enthalpy flow across should be scaled relative to Ss rather than 5,... [Pg.258]

The equilibrium, isoplethal method has a number of drawbacks [92a]. First of all, it is time-consuming. A number of samples must be raised to progressively higher temperatures and equilibrated for a time at each temperature before being separately analyzed for phase type. Secondly," vertical boundaries are difficult to isolate. And thirdly, because only a limited number of samples representing isolated points in the diagram are analyzed it is possible that phases which exist over a small range of conditions will go undetected. [Pg.100]

Bl. Bammi, J. R., Mutual influence of two freely falling spherical particles and the effects of a plane vertical boundary on a single spherical particle. M.S. Dissertation, Univ. Iowa, Iowa City, 1950. [Pg.429]

The vertical boundaries of the model were specified as adiabatic with no fluid flow. The top boundary was prescribed as a mixed boundary with specified flux and constant temperature and pressure. The bottom boundary was prescribed as a Dirichlet... [Pg.177]

As in LBNL s analysis, only half of the cross section was modelled. The domain extended from z = -150 ra to z = 150 m and from x = 0 to x = 285 m. Initial stresses and boundary conditions were similar to LBNL (Figure lb), except on the lateral vertical boundary, where zero normal... [Pg.189]

Figure 6 shows the permeability change with the stress changes when the ratio, k is fixed as 1.3. Both horizontal and vertical boundary stresses are incrementally increased at each step while keeping the k ratio constant. Due to the closure of... [Pg.272]

Figure 7 presents the permeability change with the increasing k ratio simulated by increasing the horizontal boundary stress from 2.5 MPa to 25 MPa with the fixed vertical boundary stress of 5 MPa (the k ratio changes from 0.5 to 5). To evaluate the effect of shear dilation, the results are compared with the pure elastic fracture model that does not consider the failure and dilation. [Pg.272]

Figure 3S The subdivision of subalkalic rocks using the KjO vs silica diagram. The diagram shows the subdivisions of Le Maitre et al. (1989) (broken lines with nomenclature in italics) and of Ricfcwood (1989) (nomenclature in parentheses). The shaded bands are the fields in which fall the boundary lines of Peccerillo and Taylor (1976), Ewart (1982), Innocenti et ai (1982), Carr (1985) and Middlemost (1985) as summarized by Rickwood (1989). The plotting parameters are as follows (SiC, K2O) Le Maitre et ai (1989) (broken lines) high-K/ medium-K boundary 48.0,1,2 68.0,3.1 medium-K/low-K boundary 48.0,0.3 68.0,1.2 vertical boundary at 48 % Si02-Rickwood (1989) band between shoshonidc series and high-K series 45.0,1.38 48.0,1.7 56,0,3.3 63.0,4.2 70.0,5.1 and 45.0,1.37 48,0,1.6 56.0,2.98 ... Figure 3S The subdivision of subalkalic rocks using the KjO vs silica diagram. The diagram shows the subdivisions of Le Maitre et al. (1989) (broken lines with nomenclature in italics) and of Ricfcwood (1989) (nomenclature in parentheses). The shaded bands are the fields in which fall the boundary lines of Peccerillo and Taylor (1976), Ewart (1982), Innocenti et ai (1982), Carr (1985) and Middlemost (1985) as summarized by Rickwood (1989). The plotting parameters are as follows (SiC, K2O) Le Maitre et ai (1989) (broken lines) high-K/ medium-K boundary 48.0,1,2 68.0,3.1 medium-K/low-K boundary 48.0,0.3 68.0,1.2 vertical boundary at 48 % Si02-Rickwood (1989) band between shoshonidc series and high-K series 45.0,1.38 48.0,1.7 56,0,3.3 63.0,4.2 70.0,5.1 and 45.0,1.37 48,0,1.6 56.0,2.98 ...
The functional boundary has two dimensions vertical and horizontal. The vertical boundary defines the nfe cycle stages, that is the processes which are to be included in the study. The horizontal boundary limits the number of impacts to be recorded at each life cycle stage. [Pg.81]


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See also in sourсe #XX -- [ Pg.81 ]




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