The 15th International Topical Meeting on Nuclear Reactor Thermalhydraulics, NURETH-15,
Pisa, Italy, May 12-15, 2013
An experimental study of the rewetting of a hot surface at atmospheric conditions using sub cooled liquid at various flowrates
In this study several experiments have been carried out to investigate the effect of coolant
flow-rate upon the rewetting mechanism of a vertical annular channel encircling a heated rod
at atmospheric conditions. A specifically designed and constructed experimental facility has
been used to simulate the two-phase water flow phenomena of the rewetting process at
atmospheric conditions and different degrees of inlet sub-cooling. The facility is a two-loop
water flow system with a real time computer interface for operational monitoring as well as control
and data acquisition during experiments. The wet front propagation along a stainless steel
cylindrical surface vertically positioned at top flow rewetting conditions has been
examined in the flow-rate range of 0.5 to 1.0 L min-1
, inlet water sub-cooled in the range
of 0 to 50 °C with an initial surface temperature of the rod up to 550 °C at atmospheric conditions.
The result presented in this study shows that the rewetting velocity increases with an increase
in liquid flow-rate and sub-cooling and decreases with an increase of the initial surface temperature.