Flow-through cooling for computer systems

1. A rack system for housing a plurality of computers, comprising:

a rack assembly configured to support a first stack of computers and a second stack of computers, each computer in the first stack of computers and in the second stack of computers having a front side and a back side opposite the front side, with the back side of each of the first stack of computers facing the back side of each of the second stack of computers; and

a plurality of fan assemblies configured to create an airflow through the first stack of computers and into the second stack of computers, wherein the plurality of fan assemblies comprises:

a first fan assembly in each computer in the first stack of computers, the first fan assembly configured to create an airflow entering the front side and exiting the back side of each computer in the first stack of computers; and

a second fan assembly in each computer in the second stack of computers, the second fan assembly configured to create an airflow entering the back side and exiting the front side of each computer in the second stack of computers.

2. The rack system of claim 1 , wherein:

the first stack of computers and the second stack of computers define a central plenum therebetween.

3. The rack system of claim 1 , wherein:

the plurality of computers comprises a plurality of servers.

4. The rack system of claim 1 , wherein:

the rack assembly measures less than approximately 100″ by approximately 52″ by approximately 38″.

5. A rack system, comprising:

a rack assembly configured to support a first computer and a second computer adjacent to the first computer in a back-to-back configuration, each of the first computer and the second computer having a front side and a back side opposite the front side with the back side of the first computer facing the back side of the second computer; and

at least one fan assembly configured to create an airflow entering the front side and exiting the back side of the first computer, then entering the back side and exiting the front side of the second computer;

wherein the first computer and the second computer define a central plenum therebetween; and

the at least one fan assembly is provided in the central plenum.

6. The rack system of claim 5 , wherein:

the first and second computers comprise servers.

7. The rack system of claim 5 , wherein:

the rack assembly measures less than approximately 100″ by approximately 52″ by approximately 38″.

8. A method of cooling a plurality of computers in a rack system, comprising:

supporting a first stack of computers and a second stack of computers in a rack assembly, each computer in the first stack of computers and in the second stack of computers having a front side and a back side opposite the front side, with the back side of each of the first stack of computers facing the back side of each of the second stack of computers; and

effectuating an airflow through the first stack of computers and into the second stack of computers, said effectuating the airflow comprising:

operating a first fan assembly in each computer in the first stack of computers to create an airflow entering the front side and exiting the back side of each computer in the first stack of computers; and

operating a second fan assembly in each computer in the second stack of computers to create an airflow entering the back side and exiting the front side of each computer in the second stack of computers.

9. The method of claim 8 , wherein:

the plurality of computers comprises a plurality of servers.

10. The method of claim 8 , wherein: the rack assembly measures less than approximately 100″ by approximately 52″ by approximately 38″.