Multipass heat exchangers with a single well-mixed shell pass
- Univ. of California, Berkeley (USA)
Analytical expressions for the performance of a shell and tube heat exchanger with a single, well-mixed shel pass and for two, three, or four tube passes have been available. When the number of tube passes becomes very large, the shell fluid acts as though it was well mixed laterally with a single pass normal to that of the shell side fluid; this is the case of the crossflow exchanger with both fluids well mixed and expressions for the performance of this exchanger are available also. The analysis for all of these cases is reviewed in Jakob (1957). Noted there is the early comparison of the performance of the two-pass system with that of the cross flow exchanger, typical of a very large number of passes, to indicate that for normal values of the number of transfer units the effectiveness is in both cases almost the same. Because of this, the performance as specified for the two-pass exchanger is taken to apply also for any numer of even passes, a recommendation made in all heat transfer books. Here this exchanger problem is considered again and in view of its history, and of the substantial idealization involved in the well-mixed fluid assumption that is associated witht he shell side fluid, some justification is needed for this further examination. This is based on a more unified presentation for all of the cases for both even and odd numbers of tube passes, which gives explicit expressions for the outlet temperature of the tube side fluid. A simple algebric result for the effectiveness is obtained for an even number of passes. One is not obtainable for an odd number of passes so that for this case the determination of the effectiveness involves a sequence of arithmetic equations, simpler however than a finite difference solution for the whole exchanger.
- OSTI ID:
- 5345868
- Journal Information:
- Journal of Heat Transfer (Transcations of the ASME (American Society of Mechanical Engineers), Series C); (United States), Journal Name: Journal of Heat Transfer (Transcations of the ASME (American Society of Mechanical Engineers), Series C); (United States) Vol. 110:3; ISSN 0022-1481; ISSN JHTRA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effectiveness of heat exchangers with one shell pass and three tube passes. Master's thesis
DESIGN, CONSTRUCTION, AND PERFORMANCE OF TWO COMPACT AIR COOLED SODIUM HEAT EXCHANGERS