A review of research results on two-phase flow pattrens in oil horizontal wells

This paper discusses the creation and representation of the single-phase and two-phase flow regimes in the wells. This paper focuses on the behavior of a single-phase flow in the case of vertical and horizontal wells as well as how total pressure losses are in vertical and horizontal wells. The paper then proceeds to discuss the two-phase flow in these wells but again proves to be more complicated by introducing such parameters as pressure drop, void fraction, and fluid holdup. The productivity of perforated horizontal wells is on the rise, and it has also been observed that as the superficial velocity of the air goes up, total pressure drop, mixture superficial velocity, and vacuum ratio all increase while the thickness of the liquid film undergoes a reduction. The standpipe pressure drop due to a mixture Reynolds number is noted to be essential. It is also noticed that the perforation of horizontal wells and the change distribution of perforation increased productivity; the increase of perforation density at the inlet of the horizontal wellbore and the decrease of perforation density at the outlet of the horizontal wellbore resulted in higher productivity. It was further observed that lesser axial velocity is more desirable as it reduces pressure drop but delivers greater productivity with radial velocity.