Based on the theory of pseudo-potential

an isothermal lattice-Boltzmann model for multiphase pulsatile flow in capillary tube was established. By selecting the appropriate dimensionless parameters

the simulation unit was loaded into an actual unit. Simulation results obtained by this model

such as surface tension of static drop

shape of rising bubble in large space and narrow space

were compared with theory and other scholars’ research results

and the reliability of this model was verified. Bubbly flow driven by the sinusoidal pressure wave in capillary tube was simulated. The relationship between pressure wave amplitude and periodic variation of liquid phase Re number and bubble displacement was investigated. Shape changes of vapor-liquid interface in the periodic pulsatile process was obtained. The oscillation of Re number near the boundary area was observed when the direction of liquid velocity on the boundary was changed.  The reason for this phenomenon was discussed in this paper. The effect of gravity on the pulsatile process was analyzed. Simulation results validated the empirical law that the flow pattern in the capillary tube was affected by gravity if Bond number (ratio of buoyancy force to surface tension force) Bo >2. The movement and interface form of a single liquid slug was alsoinvestigated by using numerical simulation. The research result agreed with experimental results from literatures. These simulation results provided the basis for the research of pulsatile heat pipe with capillary tube as its main component.