本文旨在提出渠道變量流之濃度擴散方 程式線性解析解,主要方法乃是將連續方程式 與擴散波動量方程式代入濃度擴散方程式中, 合併為一二階偏微分方程式。經過線性化假設 可求得其解析解。 解析解模擬天然河道,須依河川特性做 適當分段。因此求天然河道解析解,亦將河道 適當的分段,作為計算的區段。每一區段以該 段已求得之解析流速平均值,作為該段濃度擴散方程式之線性化因子,利用此法可模擬渠道 變量的濃度擴散情況。線性化因子會影響解析解 的結果,因此本文乃對線性化因子的選取提出 建議方法,以俾實際的應用。其結果與動力波 數值解及實際值比較,顯示出良好的結果。 The objective of this study is to develop a linearized analytical solution of non-inertia wave and concentration routing problem. The numerical method which is the combination of Preissmann scheme and Crank-Nicholson finite difference method is proposed here to solve nonlinear dynamic wave and concentration routiong problem. In addition to apply to regular channel, a natural channel can also be applied. The natural channel is divided into many sections. The concentration routing of each section can be obtained provided the linearized factor (mean velocity) was obtained from the flood routing equation. Compare to the nonlinear dynamic wave and field data, this method can obtain good approximation efficiently and economically.
關聯:
第五屆水利工程研討會論文集(二)=PROCEEDINGS OF 5TH CONFERENCE ON HYDRAULlC ENGINEERING，頁572-583
