Flow Pattern Study On Foam Fluid In The Wellbore

Foam fluid is a kind of typical compressible non-Newtonian fluid. This paper,based on the control equations of non-Newtonian fluid, deduces the friction coefficient calculation formula, and compiles corresponding graphics for the domestic and foreign 14 turbulent friction coefficient calculation formula. Then a comparison of relative deviation is made and chooses the turbulent friction coefficient formula. Based on the model of the steady flow in wellbore, the coupling model of unsteady fluid density, pressure and temperature of foam fluid in the wellbore is establishes and programming is conducted. This paper concludes the regularities of distribution of density, pressure, and temperature of the foam fluid along the well depth, and their corresponding changes at the same location in the wellbore at different time. The results show that when the pressure of bubble flow along the well path in horizontal wellbore gradually reduces, within the same, the longer the time, the faster it reduces; the temperature along the well path gradually rises, within the same time, the longer the time is, the faster the temperature rises; the density along the well path gradually reduces, the longer the time is, the faster it reduces; the speed along the well path gradually rises, the longer the time is, the faster the stability achieves.