Application of fuzzy comprehensive evaluation to evaluate the effect of water flooding development

Abstract

Abstract Fuzzy comprehensive evaluation (FCE) is a synthetic appraisement method based on fuzzy mathematics, and evaluation result is practical and reliable, therefore, which is widely used in petroleum, construction and many other fields. This paper applies it to the evaluation of water flooding effect of oilfield. This paper introduces the principle of FCE method and the evaluation steps. The method is applied to the evaluation of water flooding development effect, which is helpful to improve the analysis level of oil and gas field development. Compared with the traditional method, this proposed method can reflect the difference of the evaluation units. Meanwhile, the weight vector is gotten by entropy method and analytic hierarchy process (AHP), which making the evaluation results more convincing. Taking W oilfield as an example, the ten factors (e.g., reserves controlled degree of water flooding, reserves producing degree of water flooding, recovery percent of recoverable reserves, water cut, water storage rate, oil recovery rate of residual recoverable reserves, cumulative water injection, maintenance of formation pressure, comprehensive decline rate, water flooding recovery) were evaluated by proposed FCE method. Then the membership matrix is established, and the weight vector is calculated by the entropy method and the AHP. Finally, the evaluation results of the two methods are obtained by fuzzy transformation and are consistent with the actual water flooding effect. Thus, the FEC method can be used as method to accurately evaluate the effect of oil field water flooding.

Keywords

• Fuzzy comprehensive evaluation (FCE)
• Water flooding development effect
• Entropy method
• Analytic hierarchy process (AHP)