A 15-cm × 20-cm printed circuit board whose components are not allowed to come into direct contact with air for reliability reasons is to be cooled by passing cool air through a 20-cm-long channel of rectangular cross-section 0.2 cm × 14 cm drilled into the board. The heat generated by the electronic components is conducted across the thin layer of the board to the channel, where it is removed by air that enters the channel at 15°C. The heat flux at the top surface of the channel can be considered to be uniform, and heat transfer through other surfaces is negligible. The velocity of the air at the inlet of the channel does not exceed 4.55 m/s and the surface temperature of the channel remains under 50°C. Assume that the flow is fully developed in the channel.
Required:
Determine the maximum total power of the electronic components that can safely be mounted on this circuit board. Please provide the answer in Watt (W).