基于正交曲线网格的河道地形插值方法及应用

Channel Terrain Interpolation Method and Its Application Based on Orthogonal Curve Grid

传统的插值方法在采样河道地形横断面分布稀疏情况下,无法有效获得弯曲河道高精度插值结果,亟须研究有效的弯曲河道地形插值新方法,对河道演变及其规律进行定量分析。为此,提出了一种基于正交曲线网格的河道地形插值方法(OCGI),首先沿横断面进行线性插值,然后沿纵向网格线进行插值,弥补了纵向采样点空间分布不足的缺陷,且考虑了河势变化,将插值范围控制在网格分布的区域。应用实例表明:该方法比反距离加权法(IDW)和普通克里金法(KG)能得出更合理的结果,可应用于黄河口尾闾等弯曲河道的地形插值。

The traditional interpolation method can’t effectively obtain the high-precision interpolation results of curved channel when the sampling channel topographic cross⁃section is sparse.It is urgent to study an effective new method of curved channel topographic interpolation to quantitatively analyze the channel evolution and its law.In this paper,a channel terrain interpolation method(OCGI)based on orthogonal curve grid was proposed.This method firstly performed linear interpolation along the transverse direction,and then interpolated along the lon⁃gitudinal grid line,which made up for the defect of insufficient spatial distribution of longitudinal sampling points.Considering the change of river regime,the interpolation range was controlled in the area of grid distribution.The application shows that this method can give more rea⁃sonable results than that of IDW and KG methods in cross⁃section sampling data,and can be applied to topographic interpolation of curved channels such as the tail of the Yellow River estuary.