A study on modelling of OSV in subcooled flow boiling

Abstract

Using the available knowledge on the flow regime transition from bubbly flow to slug flow in gas-liquid two-phase flow, it was postulated that global bubble coalescence occurs when the bubble layer void fraction near the heated wall reaches the critical value to cause the onset of significant void (OSV) in subcooled flow boiling. The values of liquid subcooling at OSV predicted based on this assumption agreed with those by Saha and Zuber’s correlation, suggesting that the postulated mechanism of OSV is plausible.