Abstract

Various forces acting on a bubble growing on a horizontal smooth and enhanced tube have been evaluated by using the measured geometric bubble data. Great effort has been made to accurately evaluate the dynamic forces. It has been shown that the dynamic forces play a more important role in the bubble growth on an enhanced surface than on a smooth surface. A correlation for predicting the bubble departure diameter from an enhanced tube has been derived from the force balance. This correlation has a form similar to that commonlv used for smooth tubes while baring a different physical meaning.