基于容量比较法的卧式罐容量表计算方法研究

在卧式罐容量计量容量比较法原理的基础上,讨论了由有限的卧式罐离散(V-H)点计算出全高度量程范围内任意点的容积值的4种计算方法。并以30m³卧式罐为对象进行了试验研究。试验结果表明:Lagrange插值方法、分段线性插值方法、三次多项式拟合方法和三次样条插值方法在中间液位区间的计算结果较为一致;三次样条插值方法计算结果与试验值偏差最小,最大偏差值23.0L,而且稳定性较好;Lagrange插值方法、分段线性插值方法和三次多项式拟合方法在低液位高度或高液位高度的偏差比中间液位区间的计算偏差大;但是在低液位高度和高液位高度区间,由于多节点时边沿振荡原因,Lagrange插值方法的计算偏差大于三次样条插值方法。

Study on Computation Algorithm for Horizontal Tank Volume Table Based on Volumetric Method

Based on the introduction on the principle of horizontal tank volumetric calibration method, four algorithms for volume table from discrete V-H data points were discussed, which are Lagrange interpolation method, piece-wise linear interpolation method, cubic polynomial fitting method and cubic spline interpolation method. A 30m³ horizontal tank is used as experimental object. Experimental result shows that the computation results of four algorithms have good con-sistence among the middle liquid level interval; for the total interval, the precision and stability of cubic spline interpolation method is best, and the maximal deviation was 23.0 L, compared to the middle of total interval, there existed bigger deviation at the lower and upper ends when Lagrange interpolation method, piecewise linear interpolation method and cubic polynomial fitting method were used; at the lower and upper ends of total interval, the computation error of Lagrange method is bigger than that of the cubic spline method due to the rim oscillation.