Abstract
The potential of winglet type vortex generator (VG) arrays for air-side heat transfer enhancement is experimentally evaluated by full-scale wind-tunnel testing of a compact plain-fin-and-tube heat exchanger. The effectiveness of a 3VG alternate-tube inline array of vortex generators is compared to a single-row vortex generator design and the baseline configuration. The winglets are placed in a common-flow-up orientation for improved tube wake management. The overall heat transfer and pressure drop performance are assessed under dry-surface conditions over a Reynolds number range based on hydraulic diameter of 220 ≤ Re ≤ 960. It is found that the air-side heat transfer coefficient increases from 16.5% to 44% for the single-row winglet arrangement with an increase in pressure drop of less than 12%. For the three-row vortex generator array, the enhancement in heat transfer coefficient increases with Reynolds number from 29.9% to 68.8% with a pressure drop penalty from 26% at Re = 960 to 87.5% at Re = 220. The results indicate that vortex generator arrays can significantly enhance the performance of fin-tube heat exchangers with flow depths and fin densities typical to those used in air-cooling and refrigeration applications.
Original language | English (US) |
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Pages (from-to) | 87-97 |
Number of pages | 11 |
Journal | International Journal of Refrigeration |
Volume | 31 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2008 |
Keywords
- Air conditioning
- Enhancement
- Finned tube
- Generator
- Heat exchanger
- Heat transfer
- Process
- Refrigeration
- Vortex
ASJC Scopus subject areas
- Mechanical Engineering
- Building and Construction