基于钻井数据反演的牙轮钻头与岩石互作用仿真

通过建立牙齿的简化破碎坑模型和牙齿微面上的受力模型来模拟牙轮钻头与岩石的互作用,由破碎坑半锥角θ和力-压入系数k共同反映钻头结构、钻井参数以及岩石性质等因素的综合影响。根据现场钻井数据,采用误差梯度下降算法结合计算机仿真技术来反演这2个模型的参数值,并使用反演得到的参数值,进行钻进过程的计算机仿真致效,所得钻头的仿真钻进曲线和机械钻速与实际钻井十分吻合。研究结果表明,基于钻井数据反演的牙轮钻头与岩石互作用仿真方法,可以通过相对简单的模型求得更加准确的结果。

Interaction simulation of cone bit and rock based on drilling parameter inversion

The interaction of cone bit and rock is simulated through establishing the simplified teeth indentation model and the force model on the teeth.The half pyramidal angel θ of the indentation and coefficient κ express the comprehensive effect of drilling bit structure,drilling parameter and rock property.According to field drilling data,the parameter values of the two models are inversed by using error gradient descending method and computer simulation technology.Using the values,a computer simulation about the process of drilling is performed,and the simulation drilling curve and rate of penetration are very similar to the drilling data in the field.The research proves that a more accurate result can be got from relatively simplified models by a simulation method of inversing interaction between cone bit and formation based on drilling data.