US 5,720,338 A · Two-phase thermal bag component cooler

Abstract

A two-phase liquid cooling system for an electronic component comprised of flexible sealed bag which is partially filled with a liquid coolant. Sufficient residual non-condensing gas is maintained in the bag so that some of the gas dissolves in the liquid coolant when the device is not operating and at ambient temperature. During warmup, the residual gas comes out of solution and creates nucleation sites that assist in initiating boiling. The bag is air and fluid-impermeable, and has sufficient flexibility such that as coolant vaporizes, the bag expands to maintain the internal bag pressure substantially the same as the ambient environmental pressure. The bag may also be provided with a metal heat spreader plate which passes through a wall of the bag an assists with transferring heat from the component to the coolant. The heat spreader plate may be specially treated to allow the flexible bag material to by directly heat sealed to the plate and to provide nucleation sites to enhance coolant boiling.

Claims38

Dependent claims

An apparatus for absorbing heat generated by a heat generating component, the component producing heat at temperatures that span an operating temperature range, the apparatus comprising:

a flexible, sealed bag having an internal compartment formed therein which includes an evaporation region and a condenser region, the bag being disposed along an outer surface of the component;
a quantity of liquid only partially filling the internal compartment formed within the bag such that simultaneous boiling and condensing of the liquid occurs in the bag when the component generates heat during operation, wherein the bag is sufficiently flexible that an internal pressure of the bag remains substantially constant over the operating temperature range of the heat generating component.

An apparatus for cooling a heat dissipating component, the apparatus operating in an environment with an ambient pressure over a temperature range and comprising:

a hermetic bag enclosure having an interior comprising an evaporator region and a condenser region, the bag being in thermal contact with the component, thereby conducting heat dissipated by the component into the interior of the enclosure, wherein the enclosure has sufficient flexibility such that the pressure within the enclosure remains substantially at the ambient pressure over the entire operating temperature range of the heat dissipating component;
and
a liquid coolant disposed within the hermetic enclosure, the liquid coolant having a sufficiently low boiling point such that the liquid coolant is changed to a vapor by the heat dissipated by the component while the component is operating within its normal operating temperature range, and such that simultaneous boiling and condensing of the liquid occurs in the bag.

Dependencies are inferred from the claim text.

Two-phase thermal bag component cooler

Life of this patent

Two-phase thermal bag component cooler

Life of this patent

Abstract

Claims38