Cross-flow pattern

The EDV Wet Scrubbing System utilized proprietary nozzles to produce high-density water curtains through which the gas must pass. Each nozzle sprays water droplets that move in a cross-flow pattern relative to the flue gas. These cover the entire gas stream and uniformly flush the vessel s surfaces clean. The spray nozzles are nonclogging and are designed to handle highly concentrated slurries. 

For reasons of compactness of equipment, the paths of both fluids may require several reversals of direction. Two of the simpler cases of Figure 8.3 are (b) one pass on the shell side and two passes on the tube side and (c) two passes on the shell side and four on the tube side. On a baffled shell side, as on Figure 8.4(c), the dominant flow is in the axial direction, so this pattern still is regarded as single pass on the shell side. In the cross flow pattern of Figure 8.5(c),... 

Figure 2. A checker board pattern of clamping pressure distribution on the active area of cell measured by Pressurex pressure sensitive film the flow channels in bipolar plates are arranged in a cross-flow pattern red indicates higher pressure.

In the continuous processing, a steady-state flow of luminous gas is established and maintained for the duration of operation, e.g., 1 month, without interruption. Due to the factors described above, it takes some time, e.g., 30 min, to establish a steady-state flow of luminous gas. Once a steady state is established, it can be maintained it for sufficient time to allow continuous processing. Substrates are fed into the steady-state flow of luminous gas in a cross-flow pattern. The rate of transport of substrate and the length of the path in the luminous gas phase determine the treatment time. 

In the case of the downward air flow pattern, the belt is porous, whereas in the case of the cross flow pattern, the belt may be solid. The selection of air flow/belt design would depend on the particle size and shape of the product being dried. One would choose a porous belt when drying a large granular material which would not fall through the pores of the belt (which can be a wide metal or nylon wire mesh or, with a smaller particle size, could be a tight braided type screen). For very small particles, or those which... 

Fig. 10.9 Cell model to represent cross-flow pattern on distillation tray...

Fig. 10.10 Cell model to represent cross-flow pattern on distillation tray. Ethyiene glycoi synthesis top row), methyl formate synthesis (bottom row). Well-mixed liquid (left) and liquid plug flow with dispersion for four cells (right)... 

An ideal cross-flow pattern is given in Fig. 13.3-4b, where the feed stream is in plug flow and the permeate flows in a normal direction away from the membrane without mixing. Since the feed composition varies along its flow path, the local permeate concentration also varies along the membrane path. 

This model assumes no mixing in the permeate side and also no mixing on the high-pressure side. Hence, the permeate composition at any point along the membrane is determined by the relative rates of permeation of the feed components at that point. This cross-flow pattern approximates that in an actual spiral-wound membrane... 

The basic flow patterns in a heat exchanger are countercurrent How, co-cunent (parallel) flow, and cross flow, see Figure 2, For oountercuiient flow pattern, two flow streams are flowing in opposite direction to each other. For co-current flow pattern, two flow streams are flowing in the same direction. For cross flow pattern, two flow streams are flowing at an angle to each other. 

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