Performance Comparison of Novel Thin Miniaturized Piezo Actuated Dual Cooled Jet

Transcription

1 Performance Comparison of Novel Thin Miniaturized Piezo Actuated Dual Cooled Jet Today: Blowers Tomorrow: Dual Cooled Jet Peter de Bock GE Global Research

2 Dual Cooled Jets What are they? Microfluidic device Two metal disks with Piezo elements driven with AC voltage First developed for flow control Thin form factor ~ 1 mm Bracket Piezo element Suspension Metal Shim Flow Opening 2 / Footer goes here / 2012 <DATE MEPTEC HERE>

3 Dual Cooled Jets How do they work? Two piezo disk moving at >100Hz frequency Works in both air and dielectric fluids Minimal power consumption ~ mw No bearings or mechanical moving parts - Reliable DCJ single orifice pumping similar to human lungs DCJ High-Speed video 33.3x slow motion 3 / Footer goes here / 2012 <DATE MEPTEC HERE>

4 Dual Cooled Jets Flow production Air is ejected from device at high velocity in center Highly pulsed flow > 100 Hz Vortices induced entrain additional flow Highly turbulent air flow created, ideal for disrupting boundary layer/heat transfer Only flow at boundary layer contributes to heat transfer DCJ Flow 500 Hz F A N DCJ DCJ Moderate Heat Transfer Superior Heat Transfer Superior Heat Transfer 4 / Footer goes here / 2012 <DATE MEPTEC HERE>

5 Computational models Direct impingement results within 5% (Utturkar et al, IMECE 2007) Computational methodology- (Utturkar and Arik, ASME J of Heat Transfer, 2007) 5 / Footer goes here / 2012 <DATE MEPTEC HERE>

6 5V DC to AC driver development GE development of miniaturized low cost/ low profile circuit Input: 5V DC Output high quality AC Power consumption: 1 DCJ: 283 mw 2 DCJs: 325 mw (~163mW per device!) Future vision: ASIC 2 Dual Cool Jets Hz Sampling rate 6 / Footer goes here / 2012 <DATE MEPTEC HERE>

7 Why would you use a Piezo Actuated Dual Cooled Jet? 7 / Footer goes here / 2012 <DATE MEPTEC HERE>

8 Dual Cooled Jets Thin form factor 1mm device (estimated total 3 mm installed height) Low noise <30-35dB No bearings/grease reliable Can be made in different shapes Does not require magnets Good for local heat transfer augmentation Low power consumption Simple Low cost 8 / Footer goes here / 2012 <DATE MEPTEC HERE>

9 Preferred Coolant for most applications?: Air Challenge: Robust/Reliable Air Cooling Systems -Qualification Testing Sand&dust Shock Vibration Salt Fog Temperature Cycle EMI System Power density + Reliable - Capable - Less Reliable + Capability Challenging for Fans bearing/bushing failures: device overheat, sparking Operating Environment Temperature 9 / Footer goes here / 2012 <DATE MEPTEC HERE>

10 Dual Cool Jet Technology Piezo Actuated Dual Cooled Jet as intermediate flow option - Two piezo disk moving at Hz - Provide direct pulsed air over heat sink/hot chip System Power density + Reliable - Capable + + Reliable + + Capability - Less Reliable + Capability Operating Environment Temperature 10 / Footer goes here / 2012 <DATE MEPTEC HERE>

11 Potential Applications Providing airflow to applications that benefit from thin form factor air mover such as DCJ DCJ Impingement on hot component Alternative for thin laptop/ultrabook cooling? 11 / Footer goes here / 2012 <DATE MEPTEC HERE>

12 Experimental Characterization 12 / Footer goes here / 2012 <DATE MEPTEC HERE>

13 Enhencement Factor Heat transfer performance V 40 V 60 V SJ Frequency (Hz) EF Q [ Q FC jet FC ] T h [ FC jet h FC ] T Disk Natural Frequency Frequency: Round ~600Hz Square ~ 175Hz Heat transfer enhancement peaks ~600 Hz which coincides the first mode of natural frequency of round piezo actuator design 13 / Footer goes here / 2012 <DATE MEPTEC HERE>

14 Flow performance Air flow characterization experiment Step1: Close valve, measure ΔP max, zero flow Pressure head Flow Acknowledgements: Kimber et al. Stokes Institute 14 / Footer goes here / 2012 <DATE MEPTEC HERE>

15 Flow performance Air flow characterization experiment Step1: Close valve, measure ΔP max, zero flow Step2: Open valve, throttle ΔP zero, read Q max Pressure head Flow Acknowledgements: Kimber et al. Stokes Institute 15 / Footer goes here / 2012 <DATE MEPTEC HERE>

16 Flow performance Air flow characterization experiment Step1: Close valve, measure ΔP max, zero flow Step2: Open valve, throttle ΔP zero, read Q max Step3: Generate points in between Pressure head Flow Acknowledgements: Kimber et al. Stokes Institute 16 / Footer goes here / 2012 <DATE MEPTEC HERE>

17 Flow performance Air flow characterization experiment 17 / Footer goes here / 2012 <DATE MEPTEC HERE>

18 Flow performance Accuracy: ΔP sensor: +/ Pa Flow sensor: 0.5% reading l n /min Air flow characterization experiment DCJ High Flow Operation window DCJ Low flow 283 mw 18 / Footer goes here / 2012 <DATE MEPTEC HERE>

19 Flow performance Accuracy: ΔP sensor: +/ Pa Flow sensor: 0.5% reading l n /min Air flow characterization experiment DCJ High Flow Sunon product 290 mw (projected) Operation window Sunon UB5U x30x3mm DCJ Low flow 283 mw 19 / Footer goes here / 2012 <DATE MEPTEC HERE>

20 Closing thoughts Advanced Piezoelectric Dual Cooled Jet Technology(DCJs) Microfluidic air mover with thin profile Alternative air mover to fan where fans are not desired Experimental methods are being developed to evaluate thermal and flow performance Flow performance comparable to fan/blowers 20 / Footer goes here / 2012 <DATE MEPTEC HERE>

21 Acknowledgements Pramod Chamarthy John Glaser Jennifer Jackson Ram Ramabhadran Marni Rutkofsky Yogen Utturkar John Vogel 21 / Footer goes here / 2012 <DATE MEPTEC HERE>

22 Thank you for your attention 22 / Footer goes here / 2012 <DATE MEPTEC HERE>