Localized flow

Solidification. The heat of the electric arc melts a portion of the base metal and any added filler metal. The force of the arc produces localized flows within the weld pools, thus providing a stirring effect, which mixes the filler metal and that portion of the melted base metal into a fairly homogeneous weld metal. There is a very rapid transfer of heat away from the weld to the adjacent, low temperature base metal, and solidification begins nearly instantaneously as the welding heat source moves past a given location. 

Frequently, local wind systems are superimposed on the larger-scale wind systems just discussed. These local flows are especially important and may dominate when the larger-scale flow becomes light and indefinite. Local wind systems are usually quite significant in terms of the transport and dispersion of air pollutants. 

Keep in mind that the flows occurring result from the combination of the general and local flows the lighter the general flow, the greater the opportunity for generation of local flows. 

The loss of all AC power initiator includes both commercial (offsite) power and all three diesels, including the normally-running diesel. Local fault events include localized flow blockages in iho core and localized fuel faults. A lobe power imbalance initiator occurs if the individually-controlled core section powers (lobe powers)... 

A detonation shock wave is an abrupt gas dynamic discontinuity across which properties such as gas pressure, density, temperature, and local flow velocities change discontinnonsly. Shockwaves are always characterized by the observation that the wave travels with a velocity that is faster than the local speed of sound in the undisturbed mixtnre ahead of the wave front. The ratio of the wave velocity to the speed of sound is called the Mach number. 

Bi-yden, I. G. Naik, S. and Fraenkel, P. (1998). Matching Tidal Current Plants to Local Flow Conditions. Energy 23 699-709. 

The Giesekus criterion for local flow character, defined as

extensional flow, 0 in simple shear flow and — 1 in solid body rotation [126]. The mapping of J> across the flow domain provides probably the best description of flow field homogeneity current calculations in that direction are being performed in the authors laboratory. 

The existence of tribrachial structure at the base of lifted flame implies that the stabilization of liftoff flames is controlled by the characteristics of tribrachial edge flames. The coexistence of three different types of flames dictates that the edge is located along the stoichiometric contour [52] and the premixed wings have the propagation characteristics, whose speed should balance with the local flow velocity for the edge to be stationary. In the first approximation, the propagation speed was assumed to be constant [10]. 

As will be outlined below, the computation of compressible flow is significantly more challenging than the corresponding problem for incompressible flow. In order to reduce the computational effort, within a CED model a fluid medium should be treated as incompressible whenever possible. A rule of thumb often found in the literature and used as a criterion for the incompressibility assumption to be valid is based on the Mach number of the flow. The Mach number is defined as the ratio of the local flow velocity and the speed of sound. The rule states that if the Mach number is below 0.3 in the whole flow domain, the flow may be treated as incompressible [84], In practice, this rule has to be supplemented by a few additional criteria [3], Especially for micro flows it is important to consider also the total pressure drop as a criterion for incompressibility. In a long micro channel the Mach number may be well below 0.3, but owing to the small hydraulic diameter of the channel a large pressure drop may be obtained. A pressure drop of a few atmospheres for a gas flow clearly indicates that compressibility effects should be taken into account. 

The kinematic condition requires that no fluid can transverse the interface, i.e. the local flow velocity Wj relative to the velocity of the interface should be zero... 

Among interface capturing methods, one of the most popular and most successful schemes is the volume-of-fluid (VOF) method dating back to the work of Hirt and Nichols [174]. The VOF method is based on a volume-fraction field c, assuming values between 0 and 1. A value of c = 1 indicates cells that are filled with phase 1, and phase 2 corresponds to c= 0. Intermediate values of c indicate the position of the interface between the phases however, the goal is to maintain a sharp interface in order to identify the different fluid phases uniquely. Volumes assigned to the different phases are moving with the local flow velocity W , and therefore the evolution of c is determined by a convection equation ... 

Fractal dimension of clusters formed by flow-induced aggregation is independent of local flow type. 

Local Flow Obstruction and Surface Property EfTects 391... 

The prototype test results are correlated by using the operating parameters directly, while the basic study test results (including photographic records and experimental measurements) are used in microscopic analysis based on the local flow characteristics and their constitutive correlations. 

Local flow velocity fluctuations at the exit portion have been observed in a long boiling channel as a result of the large fluid compressibility inside the channel (Proskuryakov, 1965). Exit velocity fluctuation frequency is usually the same as the natural frequency of the channel. 

Hill, K. W F. E. Motley, F. F. Cadek, and J. E. Casterdine, 1974, Effects on Critical Heat Flux of Local Heat Flux Spikes or Local Flow Blockage in Pressurized Water Reactor Rod Bundles, ASME Paper 74-WA/HT-54, ASME, New York. (5)... 

Here, the dimensionless thickness of the momentum boundary layer A, and the dimensionless quantity, a, relating to the direction of local flow are functions of 0 they are shown graphically in Fig. 3. The average Sherwood number may be obtained by integrating Eq. (51) over the surface the result for a hemisphere may be given as [22] ... 

Local flows inside confined (protocell) volumes pumps... 

This additional Eq. (18) was discretized at the same resolution as the flow equations, typical grids comprising 1203 and 1803 nodes. At every time step, the local particle concentration is transported within the resolved flow field. Furthermore, the local flow conditions yield an effective 3-D shear rate that can be used for estimating the local agglomeration rate constant /10. Fig. 10 (from Hollander et al., 2003) presents both instantaneous and time-averaged spatial distributions of /i0 in vessels agitated by two different impellers color versions of these plots can be found in Hollander (2002) and in Hollander et al. (2003). 

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