Study on the effect of forced convection and thermal radiation on foam stability

Abstract

High expansion foam is widely used to mitigate cryogenic LNG spills, which is a major type of process safety accident. The stability of the foam affects the performance of hazard mitigation after cryogenic LNG spills. Forced convection and thermal radiation are key external factors affecting the foam stability, which depends on the foam drainage and breakage rates. The goal of this paper is to research the stability of high expansion foam under convection intensity of 0∼6 m/s and thermal radiation intensity of 0∼420 W/m2 following the actual environmental conditions through experiments and establish correlation models for predicting foam drainage rate and breakage rate based on the experimental results. The results show that increasing forced convection and thermal radiation will accelerate foam breaking, with forced convection having a greater effect, shortening the time of effective prevention in high expansion foam. The results of this work will guide high expansion foam mitigating LNG leakage accidents in complex environmental conditions.