JOHN PAUL ZARLING
Pilots at Raven Dr, Fairbanks, AK

4961463, Oct 9, 1990

Apr 26, 1989

7/343219

Stephen L. DenHartog - Hanover NH
John P. Zarling - Fairbanks AK
Francis D. Haynes - Etna NH

The United States of America as represented by the Secretary of the Army - Washington DC

F28D 1502

165 45

A thermosyphon for removing heat from a permafrost foundation, the invent can be installed in a frozen foundation with an evaporator section disposed either horizontally or with a negative (up) slope, thereby allowing the evaporator section of the thermosyphon to be buried in a more shallow location of the foundation than is possible with conventional thermosyphon devices. The thermosyphon of the invention has a condensate collection ring near the lowest point but higher than any point in the evaporator of a condenser section which extends above the permafrost foundation and into heat exchange contact with low-temperature above-ground air. Condensate formed in the condenser section by heat exchange with the air is collected in the collection ring and ducted through a condensate return tube to a desirable location within the evaporator section, usually the extreme distal end thereof. The present thermosyphon is thus capable of removing heat from a permafrost foundation or the like even when the evaporator section is disposed horizontally or at a negative slope.

5339893, Aug 23, 1994

May 8, 1992

7/880262

Francis D. Haynes - Etna NH
John P. Zarling - Fairbanks AK
William F. Quinn - Hanover NH

The United States of America as represented by the Secretary of the Army - Washington DC

E02D 1914

165 45

The present invention is directed to a hybrid thermosyphon which may be rapidly deployed to create a frozen soil barrier for containing toxic spills. In a particular embodiment, a plurality of thermosyphons are deployed for freezing the soil around and under a defined area of soil; each thermosyphon contains a working fluid and includes an evaporator section for contact with the soil for removing heat therefrom by evaporation of the working fluid. A condenser section in flow communication with evaporator section and remote from the soil transfers heat from the working fluid to ambient by heat exchange and subsequent condensation of the working fluid when the ambient is lower than the temperature of the soil. An active refrigeration stage in heat exchange relation with at least a portion of the condenser section removes heat from the working fluid by heat exchange when the ambient is above the soil temperature. Sensors may be provided for sensing the ambient temperature for selectively operating the active refrigeration stage.

5327734, Jul 12, 1994

May 15, 1992

7/883443

Francis D. Haynes - Etna NH
John P. Zarling - Fairbanks AK
William F. Quinn - Hanover NH

The United States of America as represented by the Secretary of the Army - Washington DC

F25D 2312

62260

A thermosyphon for use in frozen or unfrozen soil includes an evaporator tion embedded in the soil, a condenser section exposed to ambient air, an intermediate section connecting the two sections and a heat exchanger connected to a mechanical refrigeration source and operable to cool either the condenser or the intermediate section of the thermosyphon during periods when the ambient temperature is higher than that at which passive thermosyphonic cooling occurs.