Flow fluctuations and flow friction characteristics of lead-bismuth eutectic in a vertical tube under rolling conditions.

• Flow characteristics of LBE under rolling conditions are investigated experimentally. • The time-averaged flow frictional resistance of LBE is increased under rolling conditions. • The transverse additional force is main reason for the increase of flow resistance. • The results may be useful for the safety analysis under moving conditions. The effects of rolling motion on the flow characteristics of lead-bismuth eutectic in a vertical circular tube are investigated experimentally. The results show that the pressure drop and flow rate of the forced LBE circulation fluctuate under rolling conditions. The effect of rolling motion on the flow characteristics decreases with the increase of the corresponding static Reynolds number. The rolling motion may increase the time-averaged frictional resistance coefficient of the LBE when flow rate is low. The critical value of the impact Reynolds number is about 125,000. As a result, the time-averaged flow rate decreases. The analysis shows that it is mainly the transverse additional force caused by the rolling motion increases the frictional resistance of the LBE. An empirical correlation is established to predict the frictional resistance coefficient under rolling conditions. This study may be useful in the design and safety analysis of LBE as a working fluid under moving conditions. [ABSTRACT FROM AUTHOR]