TY - GEN
T1 - Heat transfer enhancement of a heat sink by inclined synthetic jets for electronics cooling
AU - Ayaskanta, Arya
AU - Huang, Longzhong
AU - Simon, Terrence W
AU - Yeom, Taiho
AU - North, Mark
AU - Cui, Tianhong
PY - 2013/12/1
Y1 - 2013/12/1
N2 - Rising thermal dissipation from modern electronics has increased the challenge of cooling using conventional heat sinks. In addition to fans and blowers, focus is turning to active cooling devices for augmenting performance. A piezoelectrically-actuated synthetic jet array is one under consideration. Synthetic jets are zero-net-mass-flow jets realized by a cavity with an oscillating diaphragm on one side and an orifice or multiple orifices on the other side. They generate highly unsteady jetting flows that can impinge upon heated surfaces and enhance cooling. However, the synthetic jet actuation components might interfere with other components of the electronics module, such as the fan, requiring a displacement of the cavity center from the jet array center. Herein, heat transfer enhancement by an inclined piezoelectrically- actuated synthetic jet arrangement in a heat sink for electronics cooling has been experimentally and numerically studied. A wedge-shaped platform is designed to introduce the jets with an inclined configuration into the finned channels of the heat sink. The unit is inclined to avoid interference with other components of the module. The penalty is described in terms of velocities of jets emerging from this wedge-shaped platform, compared to those from an aligned cavity-orifice design. Effects on heat transfer performance for the heat sink are documented. The jets are arranged as wall jets passing over heat sink fins. The experimental study is complemented with a numerical analysis of flow within the synthetic jet cavity. Optimization is done on the number of jets against the penalty on jet velocity for obtaining maximum cooling performance. The jets are driven by piezoelectric actuators operating at resonance frequencies of 700-800 Hz resulting in peak jet velocities of approximately 35m/s from 92, 0.9 mm x 0.9 mm orifices. The results give guidance to those who face a similar interference problem and are considering displacement of the synthetic jet assembly.
AB - Rising thermal dissipation from modern electronics has increased the challenge of cooling using conventional heat sinks. In addition to fans and blowers, focus is turning to active cooling devices for augmenting performance. A piezoelectrically-actuated synthetic jet array is one under consideration. Synthetic jets are zero-net-mass-flow jets realized by a cavity with an oscillating diaphragm on one side and an orifice or multiple orifices on the other side. They generate highly unsteady jetting flows that can impinge upon heated surfaces and enhance cooling. However, the synthetic jet actuation components might interfere with other components of the electronics module, such as the fan, requiring a displacement of the cavity center from the jet array center. Herein, heat transfer enhancement by an inclined piezoelectrically- actuated synthetic jet arrangement in a heat sink for electronics cooling has been experimentally and numerically studied. A wedge-shaped platform is designed to introduce the jets with an inclined configuration into the finned channels of the heat sink. The unit is inclined to avoid interference with other components of the module. The penalty is described in terms of velocities of jets emerging from this wedge-shaped platform, compared to those from an aligned cavity-orifice design. Effects on heat transfer performance for the heat sink are documented. The jets are arranged as wall jets passing over heat sink fins. The experimental study is complemented with a numerical analysis of flow within the synthetic jet cavity. Optimization is done on the number of jets against the penalty on jet velocity for obtaining maximum cooling performance. The jets are driven by piezoelectric actuators operating at resonance frequencies of 700-800 Hz resulting in peak jet velocities of approximately 35m/s from 92, 0.9 mm x 0.9 mm orifices. The results give guidance to those who face a similar interference problem and are considering displacement of the synthetic jet assembly.
KW - Electronics cooling
KW - Heat sink
KW - Heat transfer enhancement
KW - Synthetic jets
UR - http://www.scopus.com/inward/record.url?scp=84893021951&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84893021951&partnerID=8YFLogxK
U2 - 10.1115/HT2013-17769
DO - 10.1115/HT2013-17769
M3 - Conference contribution
AN - SCOPUS:84893021951
SN - 9780791855492
T3 - ASME 2013 Heat Transfer Summer Conf. Collocated with the ASME 2013 7th Int. Conf. on Energy Sustainability and the ASME 2013 11th Int. Conf. on Fuel Cell Science, Engineering and Technology, HT 2013
BT - ASME 2013 Heat Transfer Summer Conf. Collocated with the ASME 2013 7th Int. Conf. on Energy Sustainability and the ASME 2013 11th Int. Conf. on Fuel Cell Science, Engineering and Technology, HT 2013
T2 - ASME 2013 Heat Transfer Summer Conference, HT 2013 Collocated with the ASME 2013 7th International Conference on Energy Sustainability and the ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology
Y2 - 14 July 2013 through 19 July 2013
ER -