摘要 |
Heat transfer from the inside of a fan duct to the air is very good because the air in this region has a high velocity and is turbulent due to the rotation of the fan blades. Devices mounted on the outside of the fan duct can thus be cooled effectively. The inside surface of the duct can be modified to enhance the heat transfer as by grooving it deeply. The fan blade also can be modified to increase the air velocity and the turbulence. External fins can be added to the fan duct, and it can be shrouded so that a portion of the exit air passes through the fins back to the inlet. This decreases the mass of the exit air, for quieter operation.
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