Quenching of a very high temperature thin wire in water

Full text of publication follows: When a hot liquid comes into contact with a colder one, we may observe a vapor explosion. This is due to the intensive production of vapor caused by the high heat transfer between micronic fragments (resulting from the fine fragmentation of the hot liquid) and the coolant. An experimental apparatus called TREPAM investigates this heat transfer. In this experiment, the coolant level rises at a constant velocity over a fixed wire of tungsten, which is at a very high temperature. Measurement of the electric resistivity of the wire, which is related to the evolution of its temperature, enables the calculation of the heat transfer between the wire and the water. The heat transfer is studied in the ranges of - wire diameter of 10 to 250 μm - water subcooling of 0 to 350 deg. C - velocity of water of 0.2 to 4.6 m/s - wire temperature of 1350 to 3000 K - pressure of 1 to 210 bar Scaling analysis of the results allows to consider two extreme cases, in the first one most of the heat lost by the wire is used to heat the coolant and in the second one, most of the heat is used to vaporization. As the majority of the results corresponds to the first case, a correlation is established and the scales corresponding to this case allows to understand the parameters influence. (authors)