Two-Phase Pressure Drop Characteristics in Circular Tube under Rolling Motion

An experimental study on the pressure drop in the circular tube was carried out under rolling condition,and the transient and time averaged data were obtained.The pressure drop calculation model under rolling condition was established and agreed well with the experimental data.The effect of rolling motion on the pressure drop characteristics was researched by analyzing the experimental and calculation results.It found that the cyclical fluctuation occurs in the transient total pressure drop,while the deviation of average total pressure drop is very small compared with static condition.By analyzing the transient total pressure drop and its composition,it is found that the friction pressure drop is almost constant under rolling condition;the additional pressure drop caused by rolling motion can be ignore;and the fluctuation of gravity pressure drop is the reason of total pressure drop fluctuation.