Experimental study of the heat transfer in a thin vertical rectangular channels

Free convection cooling processes are often used in nuclear technologies as well as in vertical channel type structures of some systems, in electronic circuit board cooling and many other fields. Tr-2 reactor of Cekmece Nuclear Research and Training Center (Caiman) is plate type fueled pool type research reactor. The narrow vertical cooling channels of this TR-2 reactor are identical with a width of 2.1 mm. In case of an accident of loss of cooling event, the heat transfer in this channels are supplied by natural convection. An experimental setup was constructed to simulate the TR-2 cooling channel. Dummy fuel plates were heated by direct current and temperature measurement were done by Cu-constant thermocouples in different points. Working fluid is air. At several power and channel widths the temperature has been measured. The average Nu and Ra numbers were calculated for the channel and they are compared with numerical results