Effect of vibration parameters on the bubble absorption characteristics of working fluids R134a–DMAC in a vertical tube.

Highlights • Two-phase flow of R134a–DMAC becomes more complicated under vibration state. • Bubble jolting and disintegration phenomena are observed under vibration state. • Stability of bubble absorption is affected by vibration parameters significantly. • The maximal reduction of BAH occurred when amplitude is 0.4 mm frequency is 25 Hz. • Pressure, temperature, concentration and flow rate affects the bubble absorption. Abstract Two-phase flow pattern evolvement characteristic of working pair R134a–DMAC as well as the relationship between the bubble absorption height and vibration parameters (amplitude and frequency) were studied experimentally. Results showed that the bubble behavior and two-phase flow patterns became more complicated and disturbed under the vibration state, besides the bubble jolting and disintegration phenomena were observed. Stability of bubble absorption was also influenced by the vibration parameters. The most significant enhancement effectiveness of system vibration to the bubble absorption of R134a–DMAC occurred when amplitude was 0.4 mm and frequency was 25 Hz within the testing conditions. Finally, absorption pressure and temperature, solution flow rate and solution concentration were testified to influence the bubble absorption height and flow patterns under the vibration conditions. [ABSTRACT FROM AUTHOR]