This work presents a study of two-phase flow generated inside a rock-flow cell setup. It is characterized by a pipe section filled with fluid (oil in our studies) that is put into oscillation around its mass centre by an electric motor. This type of apparatus has been used by some research groups worldwide to mimic the flowing conditions of complex pipe multiphase flows but with the advantage of being compact in size. In this work, a rock flow cell was used to characterize stratified-wavy and slug flow regimes to investigate the phenomenological dynamics and behaviour around the liquid interface. The experimental procedure cases covered two total cell liquid loadings (30% and 75%), and the setup configuration was kept the same in terms of angular frequency oscillation (100 rpm) and oscillation angle amplitude (19°). Ultrasound Doppler Velocimetry (UDV) was used to monitor and assess the flow field velocity behaviour and distribution inside a rocking pipe, obtained through the EAM (Extended Auto-Correlation Method) velocity estimator algorithm. From the resulting velocity profile, we estimated the shear rate parameter. Furthermore, we could identify the air-oil phase interface position using the echo amplitude information. The UDV technique applied to rock-flow cell has a great potential to generate detailed flow information, which in turn can be used, for example, to validate Computational Fluid Dynamics (CFD) numerical simulations.