Miniature loop heat pipes for cooling high-rate CPUs of mobile "notebook" computers are among the latest developments of the laboratory:
the capacity is 140 W at a thermal resistance of 0.2°C/W;
the total thermal resistance in the system "evaporator wall - ambient air" is at the level of 0.2-0.7°C/W;
the length is 200-300 mm;
the evaporator diameter is 5 mm;
the mass, including the radiator and the "saddle" for the CPU location, does not exceed 50 g;
the evaporator mass is less than 4 g.
There are technical prerequisites for a further decrease in the thermal resistance.
CPU Coolers on the basis of Miniature LHPs
for cooling heat-tensioned components
of electronic devices and computer equipment
The devices have an evaporator 5mm in diameter with an active-zone length of 20mm. The evaporator is equipped with a copper interface (saddle) for the location of the object to be cooled. The condenser is a smooth-walled pipe with outer aluminum fins. The evaporator is connected to the condenser with a vapor line and a condensate line 2mm in diameter. The inherent mass of a miniature LHP is 9.3g. The total mass of the device including the interface and the fins is about 45g. The device retains efficient serviceability at any position in 1-g conditions.
air, temperature 22,6°С
water, temperature 45°С
Maximum capacity, W
Nominal capacity, W
Interface temperature at the nominal capacity, °С
Inherent thermal resistance at the nominal capacity, °С/W
Total thermal resistance "interface - cooling medium" at the nominal capacity, °С/W