测点处倾角对液位连通管式竖向位移测量的影响

摘要

Inclination angle changes when vertical deformation occurs at the measuring point.Then the accuracy and anti-interference ability of the vertical displacement measurement system are changed.Through the theoretical analysis,the effect of inclination angle on displacement measurement accuracy is studied,effect of inclination angle on system anti-interference ability is comparative analysed,the relationship between the horizontal pipe inner diameter and pipe length is derived.The results shows that:① inclination angle of measuring point can decrease measurement accuracy.② second-order nonlinear differential equations is the form of the liquid surface oscillations,"U" shaped single connected pipe considering inclination angle and liquid damping.③ with the decrease of inclination angle,liquid surface oscillations amplitude decrease,the period becomes longer.④ with the increase of horizontal pipe section area,the length of the oscillation time and oscillations amplitude increase.At the same time,liquid surface oscillations cycle shortened.⑤ the engineering example shows that peak value is significant reduced,when the horizontal pipe inner diameter is smaller than the optimum inner diameter.%结构竖向位移测点处发生竖向变形时将引起测点处倾角的变化,导致既有开放连通管式竖向位移测量结果准确性和系统抗干扰能力的改变.通过理论分析,研究了倾角对开放连通管式竖向位移测量准确度的影响,对比分析了倾角对系统抗干扰能力的影响,推导了最优抗干扰能力时水平段管道内径与管长的关系.结果表明:①测点处倾角引起测量准确度下降;②考虑测点处管路倾角、液体阻尼的单连通“U”型管内液体振荡形式为二阶非线性微分方程;③随着倾角的增加,管内液体振荡周期变长、振幅减小;④随着水平段连通管截面积的增大,管内液体振荡周期缩短、振幅增大,振荡时长增加;⑤工程实例表明,在管内径小于最优管内径时的测量结果具有显著的削峰效应.