Aqwest’s cutting edge thermal management technologies use microchannels, recirculation loops, liquid metal, and/or thermal energy storage for compact, high-performance cooling and temperature control of high-heat flux photonic / electronic devices including laser crystals, high-power laser diodes, radar amplifier, electronic inverters, and super-computers.
The development of the next generation of electronic and photonic devices requires corresponding improvement in thermal management technologies to enable handling of extremely high heat fluxes. To address this need, Aqwest developed a novel, ultra-low thermal resistance active heat sink (AHS) using liquid metal flowing at high speed in a miniature closed and sealed loop within a self-contained package. Liquid metal flow is maintained electromagnetically without any moving parts. Velocity of liquid metal flow can be controlled electronically to vary temperature.
We have successfully demonstrated AHS operation with a heat load over 200 W at a heat flux in excess of 800 W/cm2. AHS can be radiation hardened and space-qualifiable. AHS development was in-part supported by a grant from the National Science Foundation and contracts from the US Air Force.
Aqwest developed high-performance, ultra-rigid, isothermal heat exchangers for cooling of large area electronic chips, laser crystals, and optics. Our heat exchangers use water-cooled microchannels to deliver very low and spatially uniform thermal resistance. We use single-crystal silicon substrate offering high thermal conductivity, low CTE, and high Young’s modulus. Unlike copper, copper-tungsten, and molybdenum-based devices, our heat exchangers maintain optical figure under high thermal load. Interface to the heat load can be maintained isothermal to 1°C and it can be machined to a quality suitable for optical contacting. The development of the Aqwest microchannel heat exchanger was in-part supported by the DARPA and the US Army.
Ttemperature control is critical in many aerospace systems. To address this need, Aqwest develops high-performance, modular thermal switching device (TSD) for temperature control of electronics/optronics in air and space vehicles. TSD offers a very high heat flow switching ratio (> 100), thermal conductance > 10,000 W/m2-°C (> 100 greater than conventional devices), handles heat flux > 100 W/cm2, while being capable of fast response (up to 10x faster than conventional wax-based devices). TSD is also capable of binary ON/OFF as well as continuous control function. External power is not required. TSD is packaged into a simple, compact, lightweight, and modular unit with a thin form factor, which can be radiation hard and space qualifiable.
Many aerospace and commercial systems require handling of very high but intermittent heat loads. To overcome the challenge of rejecting high qualities of heat (up to mega-joule level) in a very short time, Aqwest developed a high-performance thermal energy storage system using phase-change materials (PCM) as buffers for temporary storage of heat. Compared to conventional TES approaches, the Aqwest system offers a compact and lightweight package, which can be readily militarized. Our proprietary recirculation loop boosts heat transfer rates while reducing coolant consumption and pump power by up to 75%. This becomes a key benefit on power-limited airborne platforms. The Aqwest TES development was in-part supported by contracts from the US Air Force.
1. J. Vetrovec, R. Feeler, and S. Bonham, “Progress in the Development of Active Heat Sink for High-Power Laser Diodes ,“ SPIE paper 7583-19, January 2010
2. J. Vetrovec, “High-Performance Heat Sink for Interfacing Hybrid Electric Vehicles Inverters to Engine Coolant Loop,” SAE paper No. T11PFL-0459, April 2011
3. J. Vetrovec, “High capacity, lightweight, and compact thermal energy storage (TES) technologies and systems,” Final Report, AFRL-RX-WP-TR-2008-4299, October 2008
4. J. Vetrovec, “Thermal management technology,” a course given at Solid-State and Diode Laser Technology Review – A Directed Energy Professional Society, Broomfield, June 12, 2012
5. J. Vetrovec, “Avanced Electronic Cooling Technologies,” AFRL-RV-PS-TR-2012-0135, September 2012
6. J. Vetrovec, “Active heat sink for automotive electronics,” SAE Paper No. 2009-01-0965, 2009
7. J. Vetrovec, “High-performance heat sink for solid-state lighting,” Proc. of SPIE paper no. 7231-25, 2009
8. J. Vetrovec, “Improved cooling for high-power laser diodes,” Proc. of SPIE vol. 6876, 2008
9. J. Vetrovec, “Quasi-passive heat sink for high-power laser diodes,” Proc. of SPIE Vol. 7198, 2009
10. J. Vetrovec, “Electronically controlled heat sink for high-power laser diodes,” Proc. of SPIE vol. 7325, 2009
11. J. Vetrovec, “Progress in the Development of Active Heat Sink for High-Power Laser Diodes,” Proc. of SPIE Vol. 7583, 2010
12. J. Vetrovec, “High-Performance Heat Sink for Hybrid Electric Vehicle (HEV) Inverters,” Proceedings of the 12th International Conference on Advanced Vehicle and Tire Technologies, Symposium 5, August 15-18, 2010, Montreal, Canada
13. J. Vetrovec,” Engine cooling system with a heat load averaging capability,” presentation at the SAE 2008 Congress, Detroit, April 2008.
14. J. Vetrovec, “High-Performance Heat Sink for Interfacing Hybrid Electric Vehicles Inverters to Engine Coolant Loop,” SAE paper No. 2011-01-0349, April 2011.
15. J. Vetrovec, A. S. Litt, and D. A. Copeland , “Liquid Metal Heat Sink for High-Power Laser Diodes,” SPIE vol. 8605-13, Febraury 2013.
US patent No 7464672 – Engine cooling system with overload handling capability
US Patent No 7735461 – Engine cooling system with overload handling capability
US Patent No 7467523 – Autonomous water source
US Patent No 7866176 -Autonomous Water Source