WELL DESIGN USING A COMPUTER-MODEL

In this study, the theory of nonlinear optimization is used to develop a well-design computer model to determine the optimum directional par ameters to minimize drilling depth and reduce drilling costs. The mode l uses the sequential unconstrained minimization technique (SUMT) to m inimize drilling-depth objective function. Also, the model is used to calculate well. surveys, simulate bit walk, and determine optimum lead angle to kick a well off: The minimum drilling depth is achieved at t he minimum values for kickoff point, inclination, and angle-buildup an d -dropoff rates. These minimum parameters reduce the dogleg severity, which, in turn, reduces the chances for operational problems like hig h torque and drag. The computer model has been validated by comparing a conventional design and an optimized design for a well drilled in th e Gulf of Suez. The optimization model produced less drilling depth an d lower inclination and dogleg severity.