A study on the lift-off diameter of bubbles generated on horizontal tube

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>In this study, experiments and a theoretical analysis on the lift-off diameter of bubbles generated on a horizontal tube were conducted. A force balance analysis in the direction normal to the heated surface at the moment of the bubble lift-off was performed to develop the model. According to the developed model, the bubble lift-off diameter strongly depends on the azimuthal position of the horizontal tube, the relative velocity between a bubble and the surrounding liquid, and the properties of the bubble and liquid. To validate the prediction performance of the proposed model, the dynamics of the bubble growth and sliding process was visualized using a high-speed digital video camera. The proposed model agrees well with the experimental data within an averaged relative deviation of 19.6%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A theoretical correlation for the bubble lift-off diameter on a horizontal tube. </LI> <LI> Growth and lift-off phenomena of bubbles generated on a horizontal tube. </LI> <LI> Bubble lift-off diameter depends on the azimuthal position of the horizontal tube. </LI> </UL> </P>