Liquid-air hybrid cooling in electronics equipment

1. An electronics chassis system comprising:

a housing defining an interior area, said housing having four vertical walls including a front wall, a back wall, and two sidewalls, said housing further including an upper plenum having a upper air inlet opening in said front wall and a lower plenum having a lower air inlet opening in said front wall;

a fluid cooling system disposed within said housing, said fluid cooling system including:

a heat exchanger mounted in said upper plenum of the housing proximate to an outlet opening through said back wall of said housing;

a fluid supply conduit leading from the heat exchanger to a backplane;

a fluid return conduit leading from the backplane to the heat exchanger; and

a pump for circulating cooling fluid through said conduits and said heat exchanger;

a plurality of slots disposed below the upper plenum and above said lower plenum of said housing for selectably receiving a plurality of individual electronics modules in vertical alignment between the two sidewalls, wherein said slots are spaced to provide vertical airflow channels between said lower plenum and said upper plenum, each said slot including:

a first fluid connector located at the backplane for fluidly connecting a fluid inlet of a received electronics module with said fluid supply conduit;

a second fluid connector located at the backplane for fluidly connecting a fluid outlet of a received electronics module with said fluid return conduit, wherein said pump is operative to circulate cooling fluid through an electronics modules when the electronics module is engaged with the first and second fluid connectors; and

a fan disposed within the upper plenum of said housing proximate to said back wall and said heat exchanger for displacing air through said interior area, wherein said fan is operative to:

draw a first airstream into said lower air inlet opening in said lower plenum below said slots, through said vertical airflow channels, across electronics modules disposed in said slots and into said upper plenum;

draw a second airstream into said upper air inlet opening into said upper plenum, wherein said first and second airstreams combine in said upper plenum to form a combined airstream; and

draw the combined airstream across said fan and displace said combined airstream across said heat exchanger and out said outlet opening.

2. A chassis as defined in claim 1 , wherein said first and second fluid connectors of at least two slots are fluidly connected to a common heat exchanger.

3. A chassis as defined in claim 1 , wherein said fluid cooling system further includes:

a cooling fluid reservoir.

4. A chassis as defined in claim 1 , wherein said first and second fluid connectors seal to prevent the passage of cooling fluid in the absence of an electronics module being connected thereto.

5. A chassis as defined in claim 1 , wherein the first and second fluid connectors of each of said plurality of slots are adapted to couple automatically with the fluid inlet and fluid outlet of an electronics module when the electronics module is fully engaged with one of the plurality of slots.

6. A method for use in an electronics chassis system, comprising:

engaging at least first and second electronics modules within an electronics chassis, wherein said modules are electrically connected to said chassis and wherein a fluid cooling path of each said electronics module is automatically coupled at a backplane of the electronic chassis with a fluid cooling system within the electronics chassis;

establishing a first air flow over a surface of each said electronics module; wherein establishing the airflow comprises drawing air into an inlet opening though a front wall of said chassis into a lower plenum of the electronics chassis below said modules and drawing said air vertically between said modules into an upper plenum above said modules using a fan disposed within said upper plenum of said chassis and proximate to a back wall of said chassis;

establishing a cooling fluid flow through said electronics module wherein cooling fluid circulates through said fluid cooling path and a heat exchanger within said chassis, wherein said heat exchanger is disposed in said upper plenum between said fan and an outlet opening in said back wall;

establishing a second airflow into the upper plenum of the electronics chassis via an inlet opening in the front wall of said chassis into said upper plenum, using the fan disposed in the upper plenum, wherein said second airflow bypasses said electronics modules; and

wherein the first and second airflows mix in said upper plenum between said front and back walls to form a third airflow, wherein said fan exhausts said third airflow across said heat exchanger and out of the electronics chassis via said outlet opening in the back wall of said chassis.

7. The method of claim 6 , wherein engaging comprises engaging a plurality of individual electronics modules within said electronics chassis, wherein each module is electrically connected to said chassis and wherein a fluid cooling path of each said electronics module is automatically coupled with said fluid cooling system.

8. The method of claim 7 , wherein cooling fluid from said plurality of individual electronics modules is circulated through a common heat exchanger.

9. The method of claim 7 , wherein said first airflow over a surface of said electronics module is established over a surface of each of said plurality of individual electronics modules.

10. The method of claim 9 , wherein said first airflow over a surface of each of said plurality of individual electronics module is established using a common set of fans disposed within said upper plenum of said chassis.

11. The method of claim 6 , wherein engaging further comprises:

coupling an input conduit of said fluid cooling path with a cooling fluid supply conduit within said chassis; and

coupling an output conduit of said fluid cooling path with a cooling fluid return conduit within said chassis.