<p>The heat dissipated by the objects (4) packed tightly on the top surface (2) of the heat exchanger is taken away by fluid (7) driven by a pump (6) through lower and upper chambers (13, 12) sepd. by a thermally conductive partition (14). The fluid gives up its heat to a cooler (8) in the air stream from a fan (9). The chambers are interconnected by an opening (15) in the partition. The outlet (11) from the upper chamber (12) is sited above the inlet (10) to the lower chamber (13). <IMAGE></p>
