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66131_Ludwig_CH10F 5/30/2001 4:35 PM Page 181

Heat Transfer 181

Figure 10-108. Uncorrected nucleate boiling coefficient. (Used by permission: Chen, Ning Hsing. Chemical Engineering, V. 66, No. 5, ©1959.
McGraw-Hill, Inc. All rights reserved.)

3. Apply the tube size multiplier from table associated
with Figure 10-108 and also the multiplier for pressure
correction from Figure 10-109. Note that for high pres-
sure systems a pressure can become quite large, and
some designers limit it to an arbitrary value of about
3,000.

Suggested Procedure for Vaporization with Sensible
Heat Transfer

1. Follow the general procedure for vaporization only.
2. Determine the sensible heat load separate from vapor-
ization.
3. For organic liquids, evaluate the natural convection
film coefficient from Figure 10-103. Equation 10-29
may be used for the inside horizontal tube by multiply-
ing the right side of the equation by 2.25 (1 0.010 Figure 10-109. Pressure correction factor. (Used by permission:
1/3
Gr a )/log Re. Chen, Ning Hsing. Chemical Engineering, V. 66, No. 5, ©1959.
4. Calculate the required area for sensible heat transfer. McGraw-Hill, Inc. All rights reserved.)