三角函数型增长曲线预测油田开发指标

Growth Curves Expressed by Trigonometric Function to Predict Indexes of Oilfield Develop ment.

提出了用三角函数表示的一类用于油田开发指标预测的增长曲线共6条,从而进一步完善和丰富了现有的增长曲线法。提出和推导了它们的Np—t、Qt—t、Qt—Np关系式、(Np/NRmax)Qtmax准数计算式以及参数求解式。其特性研究表明,它们特性相近;(Np/NRmax)Qtmax变化范围为0～0.36785,属于峰值产量出现在油田开发初期的情况,其Qt—Np关系为一不对称的拱形曲线。提出了求取曲线参数的过原点重复线性回归法。双河油田的实例表明该方法有一定实用价值。

Six growth curves used for prediction of oilfield development indexes expressed with trigonometric function are proposed,thus perfecting and abounding in the existed growth curve methods further.The cumulative production(N p )vs time (t),production(Q t )vs t,Q t vs N p ,calculation formulae of the ratio of N p to maximum recoverable reserves(N Rmax )corresponding to the peak production(Q tmax ),(N p /N Rmax ) Qtmax ,criterion,and the formulae for obtaining the param eters of the growth curves were proposed and derived.Study of these growth curves indicate that they are similar in characteristics;(N p /N Rmax ) Qtmax ranges from0to0.36785,which belongs to situation of peak procuction Q tmax appears in the early stage of oilfield development;Q t vs N p for them assumes dissymmetrical arched curves on the rectangular coordinates.Moreover,the repeated linear regression method passed the origin for obtaining the parameters of these curves is presented.A case from Shuanghe oilfield shows that these growth curves have certain applicable values