阶梯水平井轨迹优化设计

阶梯水平井轨迹优化以设计井深或者摩阻为目标函数,这些都是基于纯技术层面上的,对经济和钻井安全考虑较少。根据其特点,提出了阶梯水平井井眼轨迹的最优化设计方法,以安全、有用和费用最低为井眼轨迹的设计原则,根据阶梯水平井井眼轨迹的设计原理,应用数学优化理论,建立了追求费用最低的最优井身轨迹的目标函数,这是一个非线性有约束的目标函数,利用外罚函数法可以对其求解,进而求得最优井身轨迹。现场试验表明,提出的阶梯水平井井眼轨迹最优化设计方法是正确的、可靠的,可以满足现场要求。

Optimal design of trajectory for stepped horizontal wells

The optimization of trajectory for stepped horizontal wells takes well design depth or friction as the target function, which is only based on techniques. It hardly takes economy and the safety of drilling into account. An optimal method of designing well trajectory for stepped horizontal wells is introduced in this paper. The principle of designing well trajectory features in safety, utility, and the lowest cost. Based on the design principle of well trajectory for stepped horizontal wells and the application of the mathematic optimization theory, a target function of optimal well track is established to make the cost the least. This is a nonlinear target function with constraint, which can be solved by using the exterior penalty function method. Then the optimal well track can be obtained. Field experiment shows that the method presented in this paper is correct and reliable, which can fulfill the field requirement.