Computational Hydraulic Analysis of a Deepwater Well Drilled With Synthetic-Based Mud in a Riserless Drilling Configuration

Abstract This paper presents an analysis of the temperatures and dynamic pressures occuring in a riserless-drilling-configuration deep water well by circulating a synthetic-based mud and also discusses some aspects of the effects of gas solubility on kick detection in this new configuration. A numerical model has been developed to simulate the mud flow through the drillstring-riserless/return line system. The simulator is based on the numerical solution for the system of flow equations using finite-difference approximations. The model accounts for the pressure and temperature dependence of mud viscosity and mud density. Through a sensitivity analysis, the effects of pertinent parameters - specially the circulation rate - on the pressures generated in the system are examined. P. 347