Study on steam generator tube wastage by liquid droplet impingement erosion; Measurement of erosion rate

William, K.*; Higashi, Yuma*; Narabayashi, Tadashi*; Tsuji, Masashi*; Ohshima, Hiroyuki; Kurihara, Akikazu 

In a steam generator (SG) of sodium-cooled fast reactors, sodium and water are separated only by the wall of the heat-transfer tube. In case of tube failure such as a defect penetrating through the heat-transfer tube, it will cause high-pressure water/steam to spout into the low-pressure sodium filling outside the tube, to initiate sodium-water reaction accompanied by high heat generation. The result is a steam outflow of the reaction that might erodes/corrodes the tube wall. While the reaction steam outflow remains unterminated, it would impinge on neighboring tubes to cause their erosion/corrosion, and eventual failure. Such phenomenon of overheating tube rupture presents a serious problem to the safety of steam generator. This study is to evaluate the wastage rate of SG heat-transfer tube caused by liquid droplet impingement erosion (LDIE).