Skip to Main Content
Frequently Asked Questions
Submit an ETD
Global Search Box
Need Help?
Keyword Search
Participating Institutions
Advanced Search
School Logo
Files
File List
ucin1109015881.pdf (2.68 MB)
ETD Abstract Container
Abstract Header
NUMERICAL SIMULATIONS OF STEADY LOW-REYNOLDS-NUMBER FLOWS AND ENHANCED HEAT TRANSFER IN WAVY PLATE-FIN PASSAGES
Author Info
ZHANG, JIEHAI
Permalink:
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1109015881
Abstract Details
Year and Degree
2005, PhD, University of Cincinnati, Engineering : Mechanical Engineering.
Abstract
Extended or finned surfaces are widely used in compact heat exchangers to reduce the thermal resistance of air- or gas-side flows. Besides increasing the effective heat transfer surface area, geometrically modified finned surfaces also improve the heat transfer coefficient by altering the flow field. Wavy plate-fin surfaces have such properties and promote relatively high thermal-hydraulic performance. They are also attractive for their simplicity of manufacture and ease of use in compact heat exchangers. The current study numerically investigates the fluid flow and enhanced convection heat transfer in two-dimensional and three-dimensional wavy plate-fin passages with sinusoidal wall corrugations in the low Reynolds number regime. Constant property, periodically fully developed, and laminar or low Reynolds number forced convection are considered. The governing equations of continuity, momentum, and energy are solved computationally using finite-volume techniques. The solution procedure is based on the SIMPLE algorithm and a non-orthogonal, non-uniform grid. The influences of fin geometry (fin spacing, fin height, fin amplitude and fin length) on the enhanced heat transfer and fluid flow behaviors are investigated. The simulation results for the velocity and temperature distributions, isothermal Fanning friction f, and Colburn factor j are presented and discussed. The complex flow patterns in the wavy-fin channel are characterized by re-circulating and/or helical swirl flows with periodic flow separation and reattachment. Two flow regimes can be classified based on these results, namely, (1) low-Re streamline-flow regime where viscous forces dominate, and (2) high-Re swirl-flow regime characterized by flow recirculation and/or helical vortices. Heat transfer enhancement is observed in the swirl flow regime along with an increased pressure drop penalty, as a consequence of the periodic thermal boundary-layer thinning, strong flow mixing, and periodic generation and dissipation of vortices or re-circulating cells. In the streamline-flow regime, the flow and heat transfer behavior are similar to that in straight flow channel, though an enhanced performance is obtained. Also, results of flow visualization experiment for a two-dimensional wavy flow channel are shown to agree well with the numerical results. Finally, the computational methodology is extended to illustrate the flow behaviors in out-of-phase wavy flow passages.
Committee
Dr. Raj Manglik (Advisor)
Pages
198 p.
Subject Headings
Engineering, Mechanical
Keywords
Wavy plate-fin
;
enhanced heat transfer
;
numerical modeling and simulation
Recommended Citations
Refworks
EndNote
RIS
Mendeley
Citations
ZHANG, J. (2005).
NUMERICAL SIMULATIONS OF STEADY LOW-REYNOLDS-NUMBER FLOWS AND ENHANCED HEAT TRANSFER IN WAVY PLATE-FIN PASSAGES
[Doctoral dissertation, University of Cincinnati]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1109015881
APA Style (7th edition)
ZHANG, JIEHAI.
NUMERICAL SIMULATIONS OF STEADY LOW-REYNOLDS-NUMBER FLOWS AND ENHANCED HEAT TRANSFER IN WAVY PLATE-FIN PASSAGES.
2005. University of Cincinnati, Doctoral dissertation.
OhioLINK Electronic Theses and Dissertations Center
, http://rave.ohiolink.edu/etdc/view?acc_num=ucin1109015881.
MLA Style (8th edition)
ZHANG, JIEHAI. "NUMERICAL SIMULATIONS OF STEADY LOW-REYNOLDS-NUMBER FLOWS AND ENHANCED HEAT TRANSFER IN WAVY PLATE-FIN PASSAGES." Doctoral dissertation, University of Cincinnati, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1109015881
Chicago Manual of Style (17th edition)
Abstract Footer
Document number:
ucin1109015881
Download Count:
2,934
Copyright Info
© 2005, all rights reserved.
This open access ETD is published by University of Cincinnati and OhioLINK.