Evaporative cooling system employing liquid film evaporation from grooved evaporator surface and vapor push pump for circulating liquid

Claim 2

In combination: a vaporization chamber containing heat producing electrical apparatus to be cooled while dielectrically protected and a two phase dielectric fluid comprising a liquid and a vapor, said apparatus including at least one cooling duct extending vertically therethrough, said duct having a plurality of longitudinal extending vertical grooves in its side wall, said liquid residing at a bottom portion of the chamber and having a liquid level above the bottom of the chamber, said liquid also being distributed as a film which coats said apparatus and coats the vertical grooves of said duct, said vapor being produced by vaporization of said liquid by said heat produced by said apparatus, said vapor occupying space in said chamber above said liquid level, a condenser having one end thereof connected to and communicating with an upper portion of said vaporization chamber occupied by said vapor, a reservoir containing a predetermined mass of non-condensable dielectric gas positioned above said condenser, said condenser having another end connected to and communicating with said reservoir and said gas therein, said gas forming an interfacial contact with said vapor in said condenser at a region therein between said ends of said condenser, said vapor condensing to form liquid condensate in the condenser on one side of said interfacial contact so that the effective condensation area of said condenser lies between said one end of said condenser and said interfacial contact; distribution means in said chamber positioned above said electrical apparatus for receiving liquid condensate from said condenser and distributing the liquid condensate as a film coating said apparatus and coating the vertical grooves of said duct, and a condensate makeup pump for pumping liquid from the bottom portion of the chamber to said distribution means.

Claim 3

In combination: a vaporization chamber containing heat producing electrical apparatus to be cooled while dielectrically protected and a two phase dielectric fluid comprising a liquid and a vapor, said apparatus including at least one cooling duct extending vertically therethrough, said duct having a plurality of longitudinal extending vertical grooves in its side wall, said liquid residing at a bottom portion of the chamber and having a liquid level above the bottom of the chamber, said liquid also being distributed as a film which coats said apparatus and coats the vertical grooves of said duct, said vapor being produced by vaporization of said liquid by said heat produced by said apparatus, said vapor occupying space in said chamber above said liquid level, a condenser having one end thereof connected to and communicating with an upper portion of said vaporization chamber occupied by said vapor, a reservoir containing a predetermined mass of non-condensable dielectric gas positioned above said condenser, said condenser having another end connected to and communicating with said reservoir and said gas therein, said gas forming an interfacial contact with said vapor in said condenser at a region therein between said ends of said condenser, said vapor condensing to form liquid condensate in the condenser on one side of said interfacial contact so that the effective condensation area of said condenser lies between said one end of said condenser and said interfacial contact; distribution means in said chamber positioned above said electrical apparatus for receiving liquid condensate from said condenser and distributing the liquid condensate as a film coating said apparatus and coating the vertical grooves of said duct, and a condensate make-up pump for pumping liquid from the bottom portion of the chamber to said distribution means.

Claim 4

In combination: a vaporization chamber containing heat producing electrical apparatus to be cooled while dielectrically protected and a two phase dielectric fluid comprising a liquid and a vapor, said apparatus including at least one cooling duct extending vertically therethrough, said duct having a plurality of longitudinal extending vertical grooves in its side wall, said liquid residing at a bottom portion of the chamber and having a liquid level above the bottom of the chamber, said liquid also being distributed as a film which coats said apparatus and coats the vertical grooves of said duct, said vapor being produced by vaporization of said liquid by said heat produced by said apparatus, said vapor occupying space in said chamber above said liquid level, a condenser having one end thereof connected to and communicating with an upper portion of said vaporization chamber occupied by said vapor, a reservoir containing a predetermined mass of non-condensable dielectric gas positioned above said condenser, said condenser having another end connected to and communicating with said reservoir and said gas therein, said gas forming an interfacial contact with said vapor in said condenser at a region therein between said ends of said condenser, said vapor condensing to form liquid condensate in the condenser on one side of said interfacial contact so that the effective condensation area of said condenser lies between said one end of said condenser and said interfacial contact; distribution means in said chamber positioned above said electrical apparatus for receiving liquid condensate from said condenser and distributing the liquid condensate as a film coating said apparatus and coating the vertical grooves of said duct, and a condensate make-up pump for pumping liquid from the bottom portion of the chamber to said distribution means.

Claim 5

A hermetically sealed system comprising a chamber including heat producing electrical apparatus therein, said apparatus having at least one surface which includes a plurality of grooves therein, said at least one surface and said plurality of grooves therein being inclined toward a vertical axis of said apparatus, a reservoir located above said chamber, a condenser connected between said chamber and said reservoir and establishing communication therebetween, a two phase fluid coolant comprising a dielectric liquid and its dielectric vapor confined in said system, a noncondensible dielectric gas, said gas being largely combined in said reservoir and making contact with said vapor in said condenser, said vapor being largely confined within said chamber and extending into said condenser to the region of contact with said gas, said vapor condensing to form liquid condensate, distribution Means for receiving said liquid condensate from said condenser and distributing the liquid condensate as a film coating the grooves of said at least one internal surface and coating said apparatus, and a condensate make-up pump in said chamber for pumping liquid therein between a lower portion of said apparatus to said distribution means.

Claim 6

A hermetically sealed system comprising a chamber including heat producing electrical apparatus therein, said apparatus having at least one surface which includes a plurality of grooves therein, said at least one surface and said plurality of grooves therein being inclined toward a vertical axis of said apparatus, a reservoir located above said chamber, a condenser connected between said chamber and said reservoir and establishing communication therebetween, a two phase fluid coolant comprising a dielectric liquid and its dielectric vapor confined in said system, a noncondensible dielectric gas, said gas being largely combined in said reservoir and making contact with said vapor in said condenser, said vapor being largely confined within said chamber and extending into said condenser to the region of contact with said gas, said vapor condensing to form liquid condensate, distribution Means for receiving said liquid condensate from said condenser and distributing the liquid condensate as a film coating the grooves of said at least one internal surface and coating said apparatus, and a condensate make-up pump in said chamber for pumping liquid therein between a lower portion of said apparatus to said distribution means.