Abstract:

Determination of flow regime of drilling fluids within the pipe and annulus plays an important role in calculating the loss of hydraulic pressure, which is a parameter to govern the drilling effect. This paper determines the flow regime of drilling fluids in pipe and annulus on the basis of a data set collected from oil wells in the Cuu Long and Nam Con Son basins. A set of parameters is proposed in order to determine the regimes of drilling fluid flow. From the theory of hydraulic drilling fluid flow, the research is extended, developed, and improved. Then, numerical simulation program is provided by Matlab sofware. The results of simulating calculation show that: all drilling fluids is laminar flow in annulus and turbulent flow in pipe for drilling wells in Cuu Long, Nam Con Son basin. Furthermore, this method of simulating calculation can be used to test the designed hydraulic parameters, which in turn could assist drilling engineers to control drilling parameters to enhance drilling effectiveness.