On the Dynamics of Transition Region Flow Boiling

This is part of a series of experimental investigation and analysis of the boiling phenomena. Previously, pool boiling experiments were carried out in all boiling regions, following the design and construction of a feedback control system that allowed process operation at any point on the boiling curve including the unstable region, which is referred to here as the transition or negative-h boiling region. This paper reports the results of flow boiling dynamic analysis in this region with the necessary modifications of formulas presented earlier to properly represent the flow boiling case; in addition, this analysis gives more insight into the characteristics of a boiling region, which is often considered desirable to avoid for many engineering applications because of the characteristic instability.