一种改进的多循环油气田产量预测模型

A Modified Multi-Cycle Model for Predicting Productions of Oil and Gas Fields

生命旋回模型法是预测油气田产量的主要方法,该方法中生命旋回(产量循环)的个数是影响预测结果的重要因素。以往多是从产量变化曲线的走势或某个时间点发生的重要事件确定循环个数,受主观判断的影响较大,容易造成结果的不准确。为此,以生命旋回模型法中常用的广义翁氏模型为基础模型,建立改进的多循环广义翁氏模型,确定油气田产量预测中的循环个数,以此来改善模型的预测效果。将改进后的模型应用于大庆油田的产量预测,其对年产量的拟合效果明显优于单循环模型和多循环模型,对未来产量变化的预测能力也基本等同于加入更多循环个数后的预测模型,从而有效避免了不必要循环的加入所导致的预测时间的增加,证明了改进模型的有效性,为油气田产量预测提供了新的思路。

Life-cycle models are the main methods for production prediction in oil and gas fields,and the number of life(production)cycles in these models has significant influences on forecast results.Previous studies usually determine the number of production cycles based on the trend of production curve or important events occurring at a certain time,which tends to result in an inaccurate forecast result.The generalized Weng’s model is chosen as a base model since it is one of the most widely-used life-cycle models,a modified multi-cycle generalized Weng’s model is then established to quantitatively determine the number of cycles in oil and gas fields’production prediction,aiming at improving the prediction performance of the model.The modified model is used to predict the production of Daqing oilfield and the results show that the modified model can present a better fit than a single-cycle model and conventional multi-cycle models.Meanwhile,the modified model can give similar forecast results to those models with more production cycles,avoiding the addition of forecast time,which has proved the validity of the modified model and provided a new idea for production prediction in oil and gas fields.