水位流量关系的确立是一个难题，利用曼宁公式求解会产生较大误差。
To establish relationship between water level and water flow is a difficult problem, and to solve by using Manning's formula will engender fairly great error.
此外，由于直接采用曼宁公式计算比较困难，因此传统算法在实际计算时采取了一些近似方法。
Besides, as it is very difficult in using Manning's equation to compute directly, traditional method made some approximation in application.
因为天然河道形状复杂，故而在近似化为宽浅人工渠道并用曼宁公式处理时不可避免地会带来模型误差。
Because the situation of an actual river is so complex (not as artificially channels) that using Manning's equation will lead to error inevitably.
因为天然河道形状复杂，故而在近似化为宽浅人工渠道并用曼宁公式处理时不可避免地会带来模型误差。
Because the situation of an actual river is so complex (not as artificially channels) that using Manning's equation will lead to error inevitably.
应用推荐