Flow behavior of rapid thermal oscillation inside an asymmetric micro pulsating heat exchanger

•The temperature, inner pressure and visualization images are used to investigate flow phenomena of micro pulsating heat exchanger.•Oscillatory eruption mode – inner pressure variations are periodic with small oscillations of liquid/gas columns.•Circulation mode – partial and bulk circulations of liquid/gas columns are found in turns.•The circulating motion helps the heat transfer more active than the oscillatory eruption mode.