Value Propositions for Chip Cooling
- Dramatic increase in cooling performance without resorting to exotic methods
- 10x smaller than current state-of-the-art CPU coolers
- Exceptionally quiet operation
- Virtually immune to dust fouling
- Simple, rugged, and cost-competitive design
- Energy-efficient
Technology-Detailed Description
The hard problems faced by conventional CPU coolers
The Problem:
- The heat transfer bottleneck is the boundary layer of “dead air” that clings to the cooling fins
- Noise levels are a limiting factor in many applications
- Dust fouling degrades cooling performance
The Sandia Solution:
- The dead air is subjected to a powerful centrifugal pumping effect, providing a ~10X reduction in boundary layer thickness
- Relative motion between the cooling fins and ambient air is highly aerodynamic and thus very quiet
- High speed rotation virtually eliminates dust fouling
Some FAQ's
Performance
Q: Based on laboratory testing of early prototype devices, what level of performance is expected for a CPU cooler based on Sandia’sair bearing heat exchanger principle?
A: We expect to achieve 0.05° C/W in package that is considerably smaller and quieter than conventional high-performance CPU coolers. Because low-thermal-resistance CPU coolers are particularly susceptible to performance degradation due to cooling-fin fouling (a thin layer of dust can easily increase thermal resistance by a factor of two), the added benefit of immunity to fouling is also a crucial performance specification. Further reductions in thermal resistance would likely involve engineering trade-offs against device size and dBa rating.
Manufacturability
Q: Does the 0.001″ air gap require tight manufacturing tolerances?
A: No — the hydrodynamic air bearing gap distance is passively self-regulating.
Q: Is the surface quality/flatness spec of a conventional heat sink mating surface
adequate?
A: Yes — For example, conventional fabrication processes such as cold forging can be used.
Real-World Practicality
Q: Can the device be mounted in any orientation?
A: Yes — the air bearing assembly is held together by magnetic attraction (between the stator and permanent-magnet rotor).
Q: Is a an air bearing suspension mechanically stiff and rugged?
A: Yes — because as with other air bearings, the rate of change of the pressure lifting force with respect to gap distance is extremely large.
Q: What other types of equipment use air bearings?
A: Devices range from hard disk read–write heads to large CNC milling machine spindles.
Q: What if small (< 0.001″ ) particulates are somehow introduced into the air gap region?
A: They are swept outward and ejected by centrifugal force.
Read in full here
Anything that makes system cooler and quieter is a winner
- Dramatic increase in cooling performance without resorting to exotic methods
- 10x smaller than current state-of-the-art CPU coolers
- Exceptionally quiet operation
- Virtually immune to dust fouling
- Simple, rugged, and cost-competitive design
- Energy-efficient
Technology-Detailed Description
The hard problems faced by conventional CPU coolers
The Problem:
- The heat transfer bottleneck is the boundary layer of “dead air” that clings to the cooling fins
- Noise levels are a limiting factor in many applications
- Dust fouling degrades cooling performance
The Sandia Solution:
- The dead air is subjected to a powerful centrifugal pumping effect, providing a ~10X reduction in boundary layer thickness
- Relative motion between the cooling fins and ambient air is highly aerodynamic and thus very quiet
- High speed rotation virtually eliminates dust fouling
Some FAQ's
Performance
Q: Based on laboratory testing of early prototype devices, what level of performance is expected for a CPU cooler based on Sandia’sair bearing heat exchanger principle?
A: We expect to achieve 0.05° C/W in package that is considerably smaller and quieter than conventional high-performance CPU coolers. Because low-thermal-resistance CPU coolers are particularly susceptible to performance degradation due to cooling-fin fouling (a thin layer of dust can easily increase thermal resistance by a factor of two), the added benefit of immunity to fouling is also a crucial performance specification. Further reductions in thermal resistance would likely involve engineering trade-offs against device size and dBa rating.
Manufacturability
Q: Does the 0.001″ air gap require tight manufacturing tolerances?
A: No — the hydrodynamic air bearing gap distance is passively self-regulating.
Q: Is the surface quality/flatness spec of a conventional heat sink mating surface
adequate?
A: Yes — For example, conventional fabrication processes such as cold forging can be used.
Real-World Practicality
Q: Can the device be mounted in any orientation?
A: Yes — the air bearing assembly is held together by magnetic attraction (between the stator and permanent-magnet rotor).
Q: Is a an air bearing suspension mechanically stiff and rugged?
A: Yes — because as with other air bearings, the rate of change of the pressure lifting force with respect to gap distance is extremely large.
Q: What other types of equipment use air bearings?
A: Devices range from hard disk read–write heads to large CNC milling machine spindles.
Q: What if small (< 0.001″ ) particulates are somehow introduced into the air gap region?
A: They are swept outward and ejected by centrifugal force.
Read in full here
Anything that makes system cooler and quieter is a winner
