Fluid distribution slot distributions

The exhaust opening is modeled as a finite-sized slot with a uniform velocity distribution. The workbench and the vertical wall below the exhaust slot form a streamline of fluid flow through which the fluid does not cross and, therefore, along this line we have T = 0. Between the slot and the jet, the vertical wall is also a streamline and from the dimensionalization given... 

The design shown in Figs. I and 2 is an adaptation of the API separator. The gas boot serves as a preseparator flume, slow ing flow to 0.5 ft see (0.15 ire s), downward. This allows entrained free gas [bubbles of 400 microns 400 ft.m) or more) to nse out of the tlowstrcam. The line from the boot to the central riser and the central riser itself arc designed for fluid velocities of 2 to 4 ft/sec (0 6 to 1.2 ire s). These components act together as a forebay. evenly distributing flow to the upper slots. 

The purpose of this investigation is to find the flow features of the aforementioned jets from CFD simulations and establish their efficacy in predicting the mean flow field for which experimental results are available. For the plane and the three-dimensional wall jets, the simple point-source technique was also applied to predict the decay of the maximum velocity and the tracer concentration with the distance x. In the computations of the present study, GAMBIT ver 2.4 was used as the preprocessor and Fluent ver 6.3.26 as the processor and post processor. Based on the earlier experiences, the K-e realizable model was considered suitable for the computations. The efflux velocity was selected as 2.0 m/s and the slot height h = 0.01 m. The intensity of turbulence at the efflux section was considered as 1%. For finding the distribution of the tracers, the density of the particles was made equal to that of the ambient fluid. 

Good filtration also requires proper distribution of the brine flow over the cross-section of the bed. Rather than the pipe distributor found in many other fixed-bed applications, many designs use nozzles fixed to the support plate [109]. These allow brine to pass from the bottom head up into the filtration zone. They end in a capped section with slots to permit radial flow. A screen covers the slots. These nozzles must be leveled very carefully in an upflow filter in order to achieve uniform distribution of fluid. It is particularly critical to level the nozzles to obtain even distribution of the scouring air (see below). 

Poor fluid flow distribution can be avoided using a variety of techniques. First, sufficient plenum spaces should be allowed above and below the fixed bed. Secondly, baffle plates should be fitted when symmetrically placed inlet and outlet nozzles are used. The baffle plates, which may be solid, slotted or perforated, should be sufficiently large to ensure that the incoming fluid is redirected, its momentum is broken and it cannot impinge directly on the adsorbent particles. If balls and/or gravel are used to further aid distribution, then screens should be used to surround the baffles. Thirdly, it may be necessary to use nozzle headers in which flow can enter the bed from several nozzles along a distribution system. The holes along such a distribution system may not necessarily be of uniform size. 

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