Document Type
Thesis
Date of Award
6-30-1957
Degree Name
Master of Science in Chemical Engineering - (M.S.)
Department
Chemical Engineering
First Advisor
George C. Keeffe
Second Advisor
C. L. Mantell
Third Advisor
Joseph Joffe
Abstract
Several experimental methods have been developed for the determination of the rate of heat transfer between a pure condensing organic vapor and a cold surface. The experimental results of the earliest method, the so-called "embedded thermocouple" approach, have not been in good agreement with heat transfer values predicted by the theoretical Nusselt equation, nor has good agreement been found among the individual data, The alternate method was an indirect approach developed by Wilson and was based on the effect of cooling watt r velocity. Wilson's method provided values in close agreement with the values predicted by the Nussalt equation but was empirical in nature. nth methods have been subject to criticism.
Chu, Flitcraft and Holeman developed and tested a modification of the Wilson method based on a rigorous theoretical analysis which postulated that the film coefficient was an inverse function of the heat transferred and weld be determined by graphical means. With a few exceptions, notably toluene, this technique has provided values in good agreement with the predicted theoretical coefficients.
The purpose of this work was three-fold: to enlarge the span of opereting conditions investigated with particular reference to extension of the cooling water velocity range; to determine whether the modified Wilson method was applicable to n-propyl and n-amyl alcohol; and to investigate n-butyl alcohol which was previously tested and did not exhibit a variation of the film coefficient with the heat transferred.
The experimental results of this investigation showed the values obtained for the three alcohols to be in conformance with the behavior expected by Chu and were in food agreement with the predicted values. The Chu method was also found to be applicable over the larger eater flow range tested. In addition, the extended range provided data that allowed more accurate charting of the graphical method. The inclusion of this data was instrumental in determining the variation of the heat transfer coefficient, ho, with q for the n-butyl alcohol where none was found previously. It is felt that a similar Investigation over the extended range of water flow would clarify the variation of h for toluene, the only presently know exception to Chu's method.
Recommended Citation
Broderick, James Joseph, "Heat transfer coefficients of condensing vapors" (1957). Theses. 2515.
https://digitalcommons.njit.edu/theses/2515
