Apparatus and method for facilitating cooling of an electronics rack by mixing cooler air flow with re-circulating air flow in a re-circulation region

An apparatus comprising:

• an electronics rack, the electronics rack comprising:
• an air inlet side and an air outlet side, the air inlet and air outlet sides respectively enabling ingress and egress of air;
• at least one electronics compartment;
• at least one air moving device, the at least one air moving device being capable of causing external air to flow from the air inlet side of the electronics rack, across the at least one electronics compartment to the air outlet side of the electronics rack;
• an outlet door mounted to and at least partially covering the air outlet side of the electronics rack, the outlet door comprising a first section and a second section;
• wherein the first section and the second section of the outlet door are configured to re-direct at least a portion of exiting inlet-to-outlet air flow of the electronics rack, and to exhaust the re-directed air flow from the outlet door at a location and in a direction to facilitate mixing thereof with re-circulating exhausted inlet-to-outlet air flow from the air outlet side of the electronics rack to the air inlet side thereof, wherein mixing of the re-directed air flow and the re-circulating air flow facilitates lowering air inlet temperature at a portion of the air inlet side of the electronics rack, thereby enhancing cooling of the electronics rack;
• wherein at least a portion of exiting inlet-to-outlet air flow of the electronics rack is re-directed by the first section of the outlet door to pass through channels in the second section of the outlet door before being exhausted as the re-directed air flow from the outlet door;
• and
• wherein a cool air supply is provided to the air inlet side of the electronics rack via at least one perforated floor tile of a raised floor, and wherein cool air supply is also provided to the outlet door through an opening in the outlet door in the first section thereof in air flow communication with a further opening in the raised floor.