Friction factors correlations

Figure 2-51. Friction factor correlation for slurry flow in heterogeneous flow regime. By permission, Turian, R. M. and Yuan, T. F., Flow of Slurries in Pipelines, A/.Ch.E. Journal, vol. 23, 1977, p. 232-243.

Hartnett, S. P. and Kostic, M. /nr. Comm. Heat Mass Transfer 17 (1990) 59. Turbulent friction factor correlations for power law fluids in circular and non-circular channels. 

Friction factor correlations, smooth pipes 67 - — Darcy and Fanning 67, 68 -- — Moody 65... 

It was shown that a normalized version of the two-phase friction factor, CfTpl CfQ, is uniquely related to X. The normalizing friction factor, CfQ, is calculated from single-phase friction factor correlations using a Reynolds number calculated as if both phases flow as liquid,... 

The wall friction zw may be evaluated in terms of a friction-factor correlation based on a local Reynolds number. 

Two of the more general correlations may be considered here. The first of these is the film friction-factor correlation. From Eqs. (15), (17), and (21), it can be shown that... 

Attempts have been made to compare the experimentally measured pressure drops with various of the theories discussed in Section III, F and with the more generalized empirical two-phase friction-factor correlations of the type discussed by Dukler and Wicks (D17). Hewitt et al. (H10) have compared their experimental data for upward cocurrent flow with one such empirical correlation and with the theories of Anderson and Mantzouranis (A5) and of Dukler (D12) and Hewitt (H7). In most cases there was good qualitative agreement only. 

Figure 7-4 Friction factor correlation, upward flow.11...

Goerke et al. [29] determined mass-transfer and friction factor correlations using the Cobe VPCML Plus and Cobe CML Duo (Cobe Cardiovascular). Water and water/glycerol mixtures were used as the hquid phases. Figure 23.6 shows the variation of the Sherwood number with the Graetz number where the Sherwood number and Graetz numbers are defined as [29]... 

Today most hollow fiber BOs are designed such that the gas phase flows inside the fibers and the blood flows outside and across the fibers (Figure 23.8). Like flat sheet BOs, several investigators have used a lumped parameter approach to determine mass-transfer and friction factor correlations for BOs. Different investigators have developed slightly different correlations. The differences in the correlations are probably indicative of the level of accuracy of this approach. 

Their mass-transfer and friction factor correlations were derived for a range of Reynolds numbers between 20 and 60. 

From Re, determine the friction factor from Figure 8-9. Using the regression method in chapter one of the text, for Re, < 1000, the friction factor correlation in Figure 8-9 can be approximated by... 

Several friction factor correlations for fully developed turbulent flow in smooth, circular ducts are listed in Table 5.8. According to Bhatti and Shah [45], these formulas were derived from highly accurate experimental data for a certain Reynolds number range. 

The friction factor correlations for fully developed turbulent flow in a rough circular duct are summarized in Table 5.9. The friction factor for turbulent flow in an artificially roughed circular duct can be found in Rao [59]. 

TABLE 5.9 Fully Developed TUrbulent Flow Friction Factor Correlations for a Rough Circular Duct [48] (a = tube radius)... 

Hartnett, J. P. and M. Kostic, Turbulent Friction Factor Correlations for Power Law Fluids in circular and Non-circular Channels , Int. Comm. Heat Mass Transfer 17 59-65 (1990). 

In short-channel structures, mass/heat transfer processes have to be modeled with simultaneously hydrodynamic developing flow. For some common shapes, the apparent friction factor correlation applicable in these cases can be given by an expression of the form... 

The pressure drop is calculated from the normal friction factor correlation which is a function of Reynold s number. The viscosity value for the Reynold s number is based on the API Technical Data Book.( ) Specific heat for temperature calculations... 

The pressure drop equations can be converted to general friction factor correlations as follows. From the Ergun equation, the friction factor correlations will be... 

The friction factor correlation resulting from the equation by Gibilaro et al. (1985) becomes... 

EFFECT OF TUBE ROUGHNESS — THE OVERALL FRICTION FACTOR CORRELATION... 

The loop flow resistance is specialized to the cases that are considered in this chapter as follows. The local irreversible losses are neglected, mainly to save on equation processing. The distributed wall friction factor correlation formulation is considered in the following. 

Flows are usually turbulent on both the tube and shell sides of coiled tube heat exchangers. To calculate pressure drops for single-phase tube side flows, it is simplest to use the normal Fanning friction factor correlation for... 

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