Study on the evaluation and optimization of complex well types based on the grey relation analysis theory

Coupling the pressure drop model and the wellbore flow model , based on the grey relation project decision method and AHP theory , one evaluation and optimization method has been developed which takes the consideration of the initial productivity , the accumulative productivity , the drilling cost , the NPV and the dynamic invest payback period , and evaluates the vertical well , fractured vertical well , slanted well , horizontal well , fractured horizontal well and multibranched horizontal well and finds the best well-type.One case was presented to validate the method.