Hydrodynamic Performance

Emerson, W. H. (1967) Thermal and Hydrodynamic Performance of Plate Heat Exchangers, NEL. Reports Nos. 283, 284, 285, 286 (National Engineering Laboratories, East Kilbride, Glasgow, UK). 

These three types of trays have a common feature in that they all have separate downcomers for the passage of liquid from each tray to the one below. There is another class of tray which has no separate downcomers and yet it still employs a tray type of construction giving a hydrodynamic performance between that of a packed and a plate column. Two examples of this type of device are the Kittel plate and a Turbogrid tray(53). Design data for these trays are sparse in the literature and the manufacturer s recommendations should be sought. 

Success of rate-based multistage separation modeling is ultimately tied to underlying equipment hydrodynamics performance correlations for tray or packed columns. For example, the thickness of the film... 

The objective in membrane design is to pack as much permeation surface area into as small a space as possible to minimize operation requirements. Depending on the application, various membrane designs are used, such as flat sheet, disc tube, hollow fiber, spiral wound, and ceramic (17). Module design has a measurable effect on the hydrodynamic performance of the cross-flow membrane device. The advantages and disadvantages of different membrane modules are summarized in Table 1. 

Bernard, J. D. T., and R. W. H. Sargent, "TTie Hydrodynamic Performance of a Sieve-Plate Distillation Column, Trans. Inst. Chem. Eng. (London) 44, 1966, p. T314. 

The idealised studies of the hydrodynamic performance on the cost is demonstrated in Figure 5.4. 

The effect of increasing gas holdup on the gas-liquid interfacial area (a) is often ambiguous. This is a special situation for the STR because the power input determines the bubble diameter and hydrodynamics (Bouaifi et al., 2001 Nocentini et al., 1993), while the gas flow rate has a driving influence on bubble dynamics in other reactor designs (to be discussed in other chapters). In other words, gas holdup information does not necessarily contain any (quantitative or qualitative) information about bubble diameter and interfacial surface area for STRs such that an increase in gas holdup does not necessarily increase a (Moilanen et al., 2008). However, gas holdup is still reported as an indicator of hydrodynamic performance, gas distribution (Boden et al., 2008), and gas-liquid contacting (Garcia-Ochoa and Gomez, 2004). 

Heim F, Durand B and Chakfe N (2005), Textile heart valve prosthesis Influence of the fabric parameters on its hydrodynamic performance in vitro , Comput Methods Biomech Biomed Engin, 1,137-138. 

Babu et al. (2003) studied encapsulating proteins in reverse micelles and dissolving it in a low-viscosity solvent that can lower the rotational correlation time of the protein. They examined the applicability of several strategies for the preparation and characterization of encapsulated proteins dissolved in low-viscosity fluids that were suitable for high-performance NMR spectroscopy. Ubiquitin was used as a model system to explore various issues such as the homogeneity of the encapsulation, characterization of the hydrodynamic performance of reverse micelles containing protein molecules, and the effective pH of the water environment of the reverse micelle. 

Fouling may be defined as the formation of deposits on heat transfer surfaces which impede the transfer of heat and increase the resistance to fluid flow. The growth of these deposits causes the thermai and hydrodynamic performance of heat transfer equipment to decline with time. Fouling affects the energy consumption of industrial processes and it can also decide the amount of material employed in the construction of heat transfer equipment. In addition, where the heat flux is high, fouling can lead to local hot spots and ultimately it may result in mechanical failure, and hence an unscheduled shutdown of the equipment. 

The mass transfer coefficient is characterised by the hydrodynamic performance of the system. It was shown in the previous section that flow conditions (velocity, viscosity, density, solute diflusion coefficient) and module geometry determine the mass transfer coefficient. So far the correlations have been used for empty flow channels or tubes. However, in man> systems mrbulence promoters are present and these affect the mass transfer coefficient. For instance, spiral wound modules are applied in reverse osmosis, nanofiltration and ulL-afiltration. These modules contain spacer materials to. separate both... 

Mazumdar D, Yamanoglu G, Guthrie RIL (1997) Hydrodynamic performance of steelmaking Tundish systems A comparative study of three different Tundish designs. Steel Res 68(7) ... 

Investigation into die Hydrodynamic Performance of die AXE Bow Concept, HSMV 2002, Naples, Italy, 2002. 

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