Fluid flow control apparatus

A heat transfer apparatus, comprising:

• a heat exchanger;
• and
• a device for providing a fluid flow, the device comprising:
• at least two fluid flow drivers;
• a plenum disposed to receive a fluid flow from the at least two drivers, the plenum having a first cross-sectional area proximate the at least two drivers and a second cross-section area at a distance from the at least two drivers, the second cross-sectional area being an exit for the fluid flow;
• and
• a baffle disposed within the plenum and having a first edge restrained proximate the first erase-sectional area and a second opposing edge freely disposed proximate the second cross-sectional area;
• wherein the baffle has a surface area responsive to the fluid flow within the plenum to reduce a backflow if one of the at least two drivers is operational and another is non-operational;
• wherein the heat exchanger is disposed proximate the exit of the device and in fluid communication with the fluid flow from the device.

A device for controlling an air flow, the device comprising:

• two fans disposed in a parallel air flow arrangement;
• a plenum disposed to receive an air flow from the two fans, the plenum having a first cross-sectional area proximate the two fans and a second cross-section area at a distance from the two fans, the second cross-sectional area being an exit for the air flow;
• and
• a baffle disposed within the plenum and flexibly responsive to an air flow from each of the two fans, the baffle having a first edge restrained proximate the first cross-sectional area and a second opposing edge freely disposed proximate the second cross-sectional area;
• wherein the baffle flexes in response to a pressure differential across the baffle to reduce a backflow within the plenum if one of the two fans is operational and another is non-operational.