Experimental study of free flow and heat transfer in narrow vertical rectangular channels

Free convection cooling of electronic boards and vertical channel type structures of systems in the facilities of some installations, in the abnormal working situations, is becoming important recent years. Plate type fueled pool type research reactors, such TR-2 reactor of CHNAEM have very narrow (2.1 mm width) vertical cooling channels. In case of an accident or a loss of cooling event, the heat transfer in this channels should be accomplished by natural circulation. The adequacy of this cooling should be proved for safety consideration. A simple experimental setup was constructed to simulate a TR-2 cooling channel. Plate powers and channel widths were the parameters changed. Dummy fuel plates were heated by DC current and temperature measurements were done by Cu-Constantan thermocouples located inside the channel and around it. Average Nu and Ra numbers were calculated for the channel and they are compared with the numerical results. Working fluid was air