One way to cool chips mounted on the circuit boards of a computer is to encapsulate the boards in metal frames that provide efficient pathways for conduction to supporting cold plates. Heat generated by the chips is then dissipated by transfer to water flowing through passages drilled in the plates. Because the plates are made from a metal of large thermal conductivity (typically aluminium or copper), they may be assumed to be at a temperature, Ts, cp.

Consider circuit boards attached to cold plates of height H = 750 mm and width L = 600 mm, each with N 10 passages of diameter D = 5 mm. If operating conditions maintain plate temperatures of Ts, cp-50°C with water flow at m =0.2 kg/s per passage and Tmi =70C, how much heat may be dissipated by the circuit boards? Evaluate the properties of water at 290 K.