原始钻孔轨迹模型的建立及模拟方法的精度对比

建立原始钻孔轨迹模型,可以为各种轨迹模拟方法计算精度分析及误差因素量化分析提供数据基础。测点要素间的关系可以看作顶角、方位关于深度的函数关系,将这种函数关系模型化,可获得模型曲线的切向量关于深度的函数关系。以此为基础,用微分方法得到曲线三维坐标关于深度的导函数,再用积分方法即可得到原始钻孔轨迹模型曲线。该模型提供了不同弯曲强度条件下的原始钻孔测点要素和三维坐标,对全角半距法和最小曲率法2种模拟方法进行误差计算、对比和分析,验证了在计算精度上最小曲率法优于全角半距法。根据计算结果得出了2种方法在计算误差上的差异,并针对勘查钻孔和定向钻孔2种实际应用条件得出相应的计算精度。

Establishment of original borehole trajectory model and accuracy comparison of simulation methods

The establishment of the original borehole trajectory model can provide data basis for the calculation accuracy analysis and error factor quantitative analysis of various trajectory simulation methods.The relationship between the measuring point elements can be regarded as the functional relationship between drift angle and azimuth with respect to depth.By modeling this functional relationship，the functional relationship between the tangent vector of model curve with respect to depth can be obtained.On this basis，the derivative function of the three-dimensional coordinate of the curve with respect to the depth was obtained by the differential method，and then the original borehole trajectory model curve can be obtained by the integral method.By using the model，the elements and three-dimensional coordinates of the original borehole measurement points under different deviation Intensity conditions were provided.The error calculation，comparison and analysis of full angle half distance method and minimum curvature method were carried out.It was verified that minimum curvature method was superior to full angle half distance method in calculation accuracy.According to calculation results，the difference in calculation error between the two methods was obtained，and according to the two practical application conditions of exploration drilling and directional drilling，the corresponding calculation accuracy was obtained.