Heat transfer coefficients in agitators

FIG. 11-25 Overall heat-transfer coefficients in agitated-film evaporators. 

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 ... 

TABLE 17.10. Overall Heat Transfer Coefficients in Agitated Tanks IU Btu/(hr)(sqft)(°R]... 

FIG. 11-2S Overall heat-transfer coefficients in agitated-film evaporators. °C = (°F - 32)/1.8 to convert British thermal units per hour-square foot-degrees Fahrenheit to joules per square meter-second-kelvins, multiply by 5.6783 to convert centipoises to pascal-seconds, multiply by lO h... 

EXAMPLE 4.1 i-1. Heat-Transfer Coefficient in Agitated Vessel with Jacket... 

T. Chilton, T. Drew, R. Jebens, Heat transfer coefficients in agitated vessels, Ind. Eng. Chem. 36 (1944) 510. 

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