Velocity mapping results

Figure 4.1.5 shows an example of a PIV image and the resulting two-dimensional velocity map for a counter-... 

The spatial temperature distribution established under steady-state conditions is the result both of thermal conduction in the fluid and in the matrix material and of convective flow. Figure 2. 9.10, top row, shows temperature maps representing this combined effect in a random-site percolation cluster. The convection rolls distorted by the flow obstacles in the model object are represented by the velocity maps in Figure 2.9.10. All experimental data (left column) were recorded with the NMR methods described above, and compare well with the simulated data obtained with the aid of the FLUENT 5.5.1 [40] software package (right-hand column). Details both of the experimental set-up and the numerical simulations can be found in Ref. [8], The spatial resolution is limited by the same restrictions associated with spin... 

Resulting maps of the current density in a random-site percolation cluster both of the experiments and simulations are represented by Figure 2.9.13(b2) and (bl), respectively. The transport patterns compare very well. It is also possible to study hydrodynamic flow patterns in the same model objects. Corresponding velocity maps are shown in Figure 2.9.13(d) and (c2). In spite of the similarity of the... 

Velocity mapping has been employed in studies of 02 photophysics taking place at the one-photon [64,65], two-photon [66], and higher photon [24,25] levels. A short summary of the studies of one-photon dissociation that illustrates the importance of three-vector correlation measurements in photofragmentation of molecular oxygen will be given. Processes resulting from absorption of three or more photons will be described in more detail here since they have aspects in common with the D2 studies. 

The polystyrene simulation followed the experiments of Bell and Edie (12) with good agreement. Figure 14.8 shows the simulation results for fiber spinning nylon-6.6 with a draw ratio of 40. The figure demonstrates the wealth of information provided by the model. It shows the velocity, temperature, axial normal stress, and crystallinity fields along the threadline. We see the characteristic exponential-like drop in diameter with locally (radially) constant but accelerating velocity. However, results map out the temperature, stress, and crystallinity fields, which show marked variation radially and axially. 

The time-derivative velocity map images (Sec. 3.3.11) were also computed from the obtained Pfc(0 tpr) through finite differences. A small time shift of T = 1.0, 0.4, and 0.2 fs were tried and all gave the same results within the resolution of the figures shown. 

The usual flux velocity-angle contour map is of this quantity in a (0, ) polar coordinate system. Experimentally, it is easier to determine the relative values of the cross-section for different velocities. The results are then presented as a distribution P(6,u ) a a(9,u ) that can be normalized by integration over aU scattering angles and velocities,/du f d oE P(6, u )= 1. 

The centerline velocity increases with distance from the die exit This is due to the acceleration of the polymer film in the air-gap. The velocity map also shows that at a given distance from the die the maximum velocity occurs near the film centerline. This results from the extra die wall experienced by the film edges and the LDV technique used for measiuing the velocity. 

The highly resolved velocity profile can be mapped in the vicinity of solid boundaries such as the walls of a room and in the entire enclosure, providing relevant data for CFD boundary conditions. These data form a basis for verification of CFD results and for improvement of CFD codes. 

Two-phase flow pattern maps, observed by Revellin et al. (2006), are presented in Fig. 2.31 in mass flux versus vapor quality, and superficial liquid velocity versus superficial vapor velocity formats calculated from the test results as follows ... 

In Fig. 5.39a-d the local heat transfer coefficients derived in the horizontal tube are compared to those obtained in the 8° upward inclined pipe and presented by Hetsroni et al. (2006). The results show a clear improvement of the heat transfer coefficient with the pipe inclination. Taitel and Dukler (1976) showed that the flow regimes are very sensitive to the pipe inclination angle. In the flow regime maps presented in their work, the transition from stratified to annular flow in the inclined tube occurs for a smaller air superficial velocity than for the case of the horizontal tube. 

This phase shift depends on x0, vx0 and ax0 at the same time, i.e., on the parameters needed for spin density, velocity and acceleration mapping, respectively. In order to distinguish the three quantities of interest, more sophisticated gradient pulse sequences have been designed, resulting in phase shifts that essentially depend only on a single parameter or a selection of parameters. 

At present evaluation of POP depositions to various types of the underlying surface are under investigations. The spatial distribution of PCB-153 depositions to areas covered with forests, soil and seawater in 2000 is demonstrated in Figure 13. Depositions of this pollutant to forests, soil and seawater were estimated using different parameterizations of dry deposition velocities for different types of underlying surfaces. This resulted in considerable differences in depositions to the considered areas. As seen from the maps, the highest levels of PCB-153 depositions were characteristic of forested areas (Dutchak et al., 2004). 

The velocity vector held map of the cold flow corresponding to the high-soot case is shown in Fig. 6.46. The change in the vortex roll-up location results in reduced external air entrainment at the flame base as alluded to previously. 

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