Experimental fouling data have been analyzed on the basis of the change in overall heal transfer coefficient of the fouling test section. It is assumed that thermal hydraulic conditions in the test section remain reasonably constant for the duration of a fouling test. The model ofTaborek et al.|I| is used, and two parameters,/8,. and Rf*, that can be determined for each fouling test are derived by regression analysis. The parameter Rf* contains all the factors that influence fouling, while 1/ ?c, contains shear stress, deposit thickness, and bonding strength of the deposit. The parameter R*is the asymptotic fouling resistance and ? is the lime constant of the fouling resistance-time curve. These parameters were determined as a function of surface temperature. Limited data were available to indicate the effect of velocity on the parameters. The parameters 1/8, and R* may be used to predict the history of fouling in a heat exchanger. Until more.data are obtained and analyzed in this fashion, the values of 1/ ?c. and R* obtained in this paper should be applied at conditions for which the fouling data were obtained. A numerical example is presented.
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