Boiling of methanol and HFE-7100 on heated surface covered with a layer of mesh
Journal
International Journal of Heat and Mass Transfer
Journal Volume
44
Journal Issue
1
Pages
169-180
Date Issued
2000
Author(s)
Liu J.W.
Abstract
The performance of conventional heat exchangers, especially for single-phase flows, can be significantly improved by many augmentation techniques resulting in the design systems. Heat transfer enhancement devices are usually used to improve the performance of an existing heat exchanger or to reduce the size and cost of a proposed heat exchanger. The extended performance evaluation criteria (PEC) equations for enhanced heat transfer surfaces based on the entropy production theorem were developed to include the effect of fluid temperature variation along the length of a tubular heat exchanger and to add new information to Bejan's entropy generation minimization method assessing two objectives simultaneously. The equations originated from different design constraints and generalized the PEC for enhanced heat transfer techniques obtained using first law analysis. The heat transfer and fluid friction characteristics of 10 spirally corrugated tubes from three sources were used to illustrate the application of PEC equations. The results for various design constraints revealed that the optimum rib height/diameter ratio for the tubes was about 0.04:1.
Subjects
Boiling
Burnout
Enhancement
Mesh
Type
journal article