Rewetting of a hot horizontal surface through mist jet impingement cooling

An experimental investigation has been carried out to study the rewetting behaviour of a hot horizontal stainless steel surface during the mist jet impingement cooling. The experiments have been performed to study the rewetting behaviour for three different initial surface temperatures viz. 255, 355, 565 degrees C. An axis-symmetric nozzle has been used to develop the mist jet of constant flow rate. The variation in surface temperature has been acquired up to 20 mm downstream spatial locations away from the stagnation point. It has been observed that unlike liquid jet impingement cooling the rise in surface initial temperature increases the rewetting temperature and the wetting delay increase with rise in the initial surface temperature but the rewetting velocity reduces. Further, the maximum surface heat flux is the highest at 20 mm spatial location for 565 degrees C initial surface temperature. Whereas, at the stagnation point, the maximum surface heat flux is not affected by the change in surface initial temperature. (C) 2012 Elsevier Ltd. All rights reserved.