Apparatus and methods for providing a flow of a heat transfer fluid in a microenvironment

1. A microenvironment system for use with a heat transfer fluid, the microenvironment system comprising:

a) a microenvironment structure defining a flow passage to receive a flow of the heat transfer fluid therethrough, wherein the heat transfer fluid is a gas; and

b) a fluid handling apparatus adapted to provide the flow of the heat transfer fluid through the flow passage, the fluid handling apparatus including:

an insulated storage vessel;

a supply of a phase change material (PCM) stored in the storage vessel and convertible from a liquid phase to a gas phase to provide a pressurized drive gas, wherein the supply of the PCM includes liquid CO 2 ;

an evaporator downstream of and external to the storage vessel and adapted to boil the supply of the PCM from the liquid phase to the gas phase to form the pressurized drive gas; and

a gas driven pump operable to force the flow of the heat transfer fluid through the flow passage, wherein the gas driven pump includes a gas driven motor and a fan blade;

wherein:

the fluid handling apparatus is configured to supply the pressurized drive gas from the evaporator to the gas driven motor to drive the gas driven motor using the pressurized drive gas; and

the gas driven motor is coupled to the fan blade to rotate the fan blade to force the flow of the heat transfer fluid through the flow passage and across the evaporator to cool and remove humidity from the heat transfer fluid.

2. The system of claim 1 wherein the evaporator is adapted to transfer heat from the heat transfer fluid to the PCM.

3. The system of claim 2 wherein the PCM flows through the evaporator.

4. The system of claim 1 wherein the fluid handling apparatus further includes a superheater adapted to superheat the pressurized drive gas prior to introduction of the pressurized drive gas into the gas driven pump.

5. The system of claim 1 wherein the microenvironment is a personal microenvironment.

6. The system of claim 5 wherein the personal microenvironment includes a protective garment.

7. The system of claim 1 wherein the microenvironment is an electronic device microenvironment.

8. The system of claim 1 wherein the heat transfer fluid is air.

9. The system of claim 1 wherein the microenvironment structure and the fluid handling apparatus form a continuous closed loop flow path for the heat transfer fluid.

10. The system of claim 1 wherein the microenvironment structure and the fluid handling apparatus form an open loop flow path for the heat transfer fluid.

11. The system of claim 1 wherein the fluid handling apparatus further includes a superheater downstream of the evaporator and adapted to superheat the cooling gas using heat transferred from the heat transfer fluid.

12. A microenvironment system for use with a heat transfer fluid, the microenvironment system comprising:

a) a microenvironment structure defining a flow passage to receive a flow of the heat transfer fluid therethrough; and

b) a fluid handling apparatus adapted to provide the flow of the heat transfer fluid through the flow passage, the fluid handling apparatus including:

a gas driven pump operable to force the flow of the heat transfer fluid through the flow passage;

a supply of a phase change material (PCM) convertible from a liquid phase to a gas phase to provide a pressurized drive gas;

an insulated storage vessel, wherein the supply of the PCM is stored in the storage vessel at a pressure in the range of from about 140 to 160 psia and a temperature of between about −58 and 65° F.;

a bleed valve to maintain the pressure in the storage vessel at a desired level;

an evaporator downstream of and external to the storage vessel and adapted to boil the supply of the PCM from the liquid phase to the gas phase to form the pressurized drive gas; and

a superheater downstream of the evaporator and adapted to superheat the pressurized drive gas to a temperature of between about 40 and 80° F. prior to introduction of the pressurized drive gas into the gas driven pump;

wherein:

the fluid handling apparatus is configured to drive the gas driven pump using the pressurized drive gas from the supply of the PCM;

the heat transfer fluid is a gas;

the supply of the PCM includes liquid CO 2 ;

the gas driven pump includes a gas driven motor and a fan blade;

the fluid handling apparatus is configured to supply the superheated pressurized drive gas to the gas driven motor to drive the gas driven motor; and

the gas driven motor is coupled to the fan blade to rotate the fan blade to force the flow of the heat transfer fluid through the flow passage and across the evaporator and the superheater to cool and remove humidity from the heat transfer fluid.

13. The system of claim 12 wherein

the PCM flows through the evaporator.

14. A method for providing a flow of a heat transfer fluid through a flow passage of a microenvironment structure, the method comprising:

providing a supply of a phase change material (PCM) stored in a storage vessel and convertible from a liquid phase to a gas phase to provide a pressurized drive gas, wherein the supply of the PCM includes liquid CO 2 ;

directing the PCM in the liquid phase from the storage vessel to an evaporator downstream of and external to the storage vessel, where the supply of the PCM is boiled from the liquid phase to the gas phase to form the pressurized drive gas; and

supplying the pressurized drive gas from the evaporator to a gas driven motor of a gas driven pump to drive the gas driven motor using the pressurized drive gas, wherein the gas driven motor is coupled to a fan blade of the gas driven pump and rotates the fan blade to force the flow of the heat transfer fluid through the flow passage and across the evaporator to cool and remove humidity from the heat transfer fluid;

wherein the heat transfer fluid is a gas.