Study Of Whole Optimization Of Well Trajectory Of Cluster Wells

Well trajectory optimazition design of cluster well is one of key measures to decline well collision risk and construction cost. Based on site drilling, this paper analyses the difficulties and countermeasures of anti-collision design and construction technology of cluster well, then carries out the research of well trajectory optimazition, from the aspects of platform position optimization, well slot allocation, 3D well trajectory design and construction sequence.Main research result includes:(1) choosing “minimum horizontal displacement” and “shortest drilling depth” as the optimal index, this paper establishes platform location optimization mathematic model, and uses advanced Genetic Algorithm to solve the problem. Not only get the optimic solution, but solved the problem of premature convergence.(2) Choosing “minimum horizontal displacement from well head to target” as the optimal index, establishes the allocation of cluster wells wellhead’s mathematical model. By using advanced Hungarian algorithm to solve the model, the solving ability increases largely, and resolves the problem of multi-zero.(3) This paper makes some progress of multi-target well trajectory model. The model is more general.(4) Shortening anti-collision scanning model, this paper establishes a mathematical optimization model of construction sequence for cluster well by choosing the minimum length of anti-collision intervals as the optimal index. Genetic algorithm is chosen to optimize this issue after the mathematical model is established. By improving the genetic algorithm, it can compute optimal solution in a relatively short period of time and preferably solve the premature convergence problem.Using the Visual Studio 2008 software, this paper programmed software of “Whole optimization design of cluster wells” for the entire model and the solution process. Using the software, we could get good platform location, well slot allocation result, well trajectory design figure and optimal construction sequence. Finally, an example of cluster wells of WZ12-1B oilfield is given to calculation and analysis. This paper provides a scientific mathematical method for the whole optimization design of cluster wells.