Correlations of heat transfer

Heating or cooling of process fluids in a batch-operated vessel is common in the chemical process industries. The process is unsteady state in nature because the heat flow and/or the temperature vary with time at a fixed point. The time required for the heat transfer can be modified, by increasing the agitation of the batch fluid, the rate of circulation of the heat transfer medium in a jacket and/or coil, or the heat transfer area. Bondy and Lippa [45] and Dream [46] have compiled a collection of correlations of heat transfer coefficients in agitated vessels. Batch processes are sometimes disadvantageous because ... 

It is necessary to work with the manufacturer in sizing and rating these special units, because sufficient public data/ correlation of heat transfer does not exist to allow the design engineer to handle the final and detailed design with confidence. 

Other useful correlations of heat transfer coefficients in packed beds have been proposed. Among these is a simple relation of Calderbank and Pogorski (104)... 

An analogy exists between the transfers of heat and mass in moving fluids, such that correlations of heat transfer involving the Prandtl number are valid for mass transfer when the Prandtl number Cp/k is replaced by the Schmidt number p pkd. This is of particular value in correlating heat transfer from small particles to fluids where particle temperatures are hard to measure but measurement of mass transfer may be feasible, for example, in vaporization of naphthalene. 

McAdams el al. (Ml), 1940 Correlation of heat transfer coefficients in falling-film heaters, N e = 225-15,000. 

An alternative heat transfer model was published by Todd [17], based on a correlation of heat transfer data over a Reynold s number range from 10-3 to 10 ... 

CORRELATION OF HEAT TRANSFER RESULTS FOR MIXED CONVECTION... 

Figure 11. Correlation of heat transfer data by Equation 17...

FIGURE 11.16 Correlation of heat transfer data for longitudinally finned tubes in annuli [122]. 

R. Pfeffer, S. Rossetti, and S. Lieblein, Analysis and Correlation of Heat Transfer Coefficient and Friction Factor Data for Dilute Gas-Solid Suspensions, NASA TN D-3603, NASA, Cleveland, OH, 1966. 

In [201] the correlation between heat-transfer coefficient and longitudinal mixing coefficient was revealed. This fact determines expediency of revealing of correlation of heat-transfer processes efficiency in tubular turbulent apparatus with hydrodynamic structure of reaction mixture... 

The correlation of heat transfer of vapor condensing inside horizontal tubes is given by ... 

Figure 4.5-2. Correlation of heat-transfer parameters for transition region for Reynolds number between 2100 and 6000. (From R. H. Perry and C. H. Chilton, Chemical Engineers Handbook, 5lh ed. New York McGraw-Hill Book Company, 1973. With permission.)...

This type of analysis is useful in empirical correlations of heat-transfer data. The importance of each dimensionless group, however, must be determined by experimentation (Bl, Ml). 

Table 8 Summary of Empirical Correlations of Heat Transfer in CFB Risers...

Suh IS, Deckwer WD. Unified correlation of heat transfer coefficients in three-phase fluidized beds. Chem Eng Sci 44 1455-1458, 1989. 

Four typical correlations of heat transfer coefficient are applied to SPRAT-F in order to investigate the influence of heat transfer correlations on the MCST. The results are summarized in Table 7.38. The correlation proposed by Watts and Chou [33] gives the highest MCST in all the channels at both BOEC and EOEC. 

Some common correlations of heat transfer coefficients are reported in Table 20.4-3. These all refer to heat transfer across a solid-fluid interface because other situations either are rare or are described in different terms. Like the mass transfer correlations in Section 8.3, these are best presented in terms of dimensionless groups. The two most... 

FIG. 7. Correlation of heat transfer results for naturally induced flow with (a) uniform wall heat flux, (b) uniform wall temperature... 

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