碩士 / 國立高雄海洋科技大學 / 輪機工程研究所 / 102 / This experimental study investigates the thermal performances of a
narrow wavy channel which swings about two orthogonal axes under
single and compound rolling and pitching oscillations. Full-field Nusselt
number (Nu) images over the wavy channel wall are detected at static and
swinging conditions by infrared thermography method and examined
comparatively to highlight the influences of rolling and pitching
oscillations on heat transfer performances. A set of selected heat transfer
data illustrates the individual and interdependent influences of rolling and
pitching oscillations on the detailed Nu distributions and the
area-averaged Nusselt numbers ( Nu ). Pressure drop coefficients (f) for
isothermal flows and thermal performance factors (TPF) at static and
swinging conditions are subsequently analyzed. For this particular
channel configuration, the single rolling or pitching oscillation elevates
Nu from the static references; whereas the synergistic effects of
compound rolling and pitching oscillations with either harmonic or
non-harmonic rhythms suppress the beneficial heat transfer impacts by
single rolling or single pitching oscillations. Buoyancy effects in isolation
elevate Nu but are weakened as the relative strength of swinging force
enhances. Pressure drop coefficients (f) consistently increase as the
relative strength of swinging forces increases. At the expense of increased
pressure drop penalties for heat transfer augmentations by swinging
oscillations, the thermal performance factor (TPF) respectively increases
and decreases as Reynolds number (Re) increases with laminar and
turbulent reference conditions. Empirical heat-transfer and pressure-drop
correlations are generated to permit the evaluations of individual and
interactive effects of single and compound swinging force effects with
buoyancy interactions on Nu and f coefficients. By the aid of these Nu
and f correlations, the favorable and worse operating conditions in terms
of the swinging parameters for the TPF properties of this corrugated
wavy channel are identified.
| Identifer | oai:union.ndltd.org:TW/102NKIM0484015 |
| Date | January 2014 |
| Creators | Huang, Bo Jyun, 黃柏鈞 |
| Contributors | Chang, Shyy Woei, 張始偉 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 45 |
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