Piezoelectric translational agitation for enhancing forced-convection channel-flow heat transfer

Yeom, Taiho; Simon, Terrence W.; Lei, Huang; North, Mark T.; Cui, Tianhong

doi:10.1016/j.ijheatmasstransfer.2012.07.019

Cited by 22 publications

(7 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The combined effects of narrowchannel cross-flow and PTA agitation on heat transfer rates, pressure drops and the corresponding powers required to drive the flow through the channel against the oscillating blade were studied. At 961 Hz as the second resonance mode of the tested PTA with a 1.4 mm displacement under 60 l/min of cross-flow through the narrow channel, about 55% of heat transfer enhancements from the non-agitated references could be achieved [27]. Above all, it has revealed that the buoyancy level as well as the oscillating frequency (f), amplitude (k) and orientation angle (a) of a piezofan provided noticeable heat transfer impacts.…”

Section: Introductionmentioning

confidence: 92%

“…With two single-fined piezofans Nomenclature English symbols C p specific heat of fluid (J kg À1 K À1 ) F, G, M, N correlative coefficients f oscillating frequency of piezofan (Hz) g gravitational acceleration (m s À2 ) k f thermal conductivity of fluid (W m À1 K À1 ) L length of heating foil (m) Nu local Nusselt number over horizontal heating The enhanced heat transfer levels by the dual single-finned piezofans were consistently better than those from the single piezofan [26]. As an attempt to extend the effective cooling area with enlarged displacements for translational motion at high-frequencies, four inchannel piezoelectric translational agitators (PTA) with oval loop shell structure were fabricated and tested [27]. The oval-looped PTA generated millimeter-range translational displacements to a blade attached to the PTA shell.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Heat transfer of twin-fin piezofan at various orientations and buoyancy levels

Chang

Hwang

Chiang

et al. 2015

International Journal of Heat and Mass Transfer

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 92%

Section: Introductionmentioning

confidence: 99%

Heat transfer of twin-fin piezofan at various orientations and buoyancy levels

Chang

Hwang

Chiang

et al. 2015

International Journal of Heat and Mass Transfer

View full text Add to dashboard Cite

“…In order to characterize the combined effects of channel flow rates and translational agitation of the system, a total Reynolds number (Re tot ) was proposed by Yeom et al [35] as: (11) where Re c and Re a are the Reynolds numbers for a channel flow and translational agitation, defined as:…”

Section: Nusselt Number and Stanton Numbermentioning

confidence: 99%

High-frequency translational agitation with micro pin-fin surfaces for enhancing heat transfer of forced convection

Yeom

Simon

North

et al. 2016

International Journal of Heat and Mass Transfer

Self Cite

View full text Add to dashboard Cite

An advanced air cooling scheme that combines both active and passive cooling components is proposed and its thermal performance is demonstrated with single channel heat transfer experiments. The active cooling component, a piezoelectric translational agitator, generates strong air turbulence using a blade oscillating at a high frequency near either plain or micro pinfin surfaces in the channel. The translational agitation of the blade is realized using an oval loop shell amplifier with a piezoelectric stack actuator. The micro pin-fin surfaces were fabricated by the LIGA photolithography technique. Single channel heat transfer experiments show promising results in the combined system with the micro pin-fin surface and the agitator. For instance, the combined system heat transfer coefficients were 250% of those on smooth surfaces without agitation. The channel flow rate was 40 LPM and the Reynolds number was 3300. Measurements are presented that assess, pin fin and agitation effects on thermal performance of the proposed active heat sink system for several channel flow rates. Based on these single channel test results, a multi-channel, full-size, active heat sink system utilizing micro pin fins and translational agitators is proposed, and its thermal performance is estimated.

show abstract

“…Yeom et al [12] experimentally explored agitation for an actual-scale, single channel of the heat sink. They designed an oval loop shell with a piezo actuator to drive the agitator plates for translational oscillatory motion.…”

Section: Introductionmentioning

confidence: 99%

“…1 shows the actual heat sink with agitators, an oval loop shell bow and a piezostack. As the piezostack contracts and expands, it drives the agitator assembly inside the heat sink channel via the bow motion [12,20].…”

Section: Introductionmentioning

confidence: 99%