Bubble growth for boiling bubbly flow for R141b in a serpentine tube

Bubble growth in flow boiling of R141b in a serpentine tube was experimentally and numerically investigated. Bubble dynamics were recorded and analyzed. Bubbles formed in a straight tube experienced distinct growth phase in the next U-bend: first grew, then shrank and grew again. A single-phase flow simulation was proposed for revealing temperature and flow field in the serpentine tube. The secondary flow at bends twisted the thermal boundary layer and mix cold main stream and superheat boundary layer at wall regime. The effective superheat around the bubble interpreted the bubble behavior noted in experiments.