本文以單一圓球形固體顆粒且仿砂石粗糙表面在橫向流中的沉降落點與行為來進行研究，並發展一方式能夠初步算出其落點距離。
與光滑圓球相比，粗糙圓球在橫向流中會有更大的阻力產生，因此計算過程中，我們考慮了重力、浮力、附加質量力與阻力來計算的單一圓球固體顆粒的軌跡，並利用改變光滑球之阻力係數來調整計算結果，發現在光滑球體1.45倍阻力係數時，能夠符合大部分的實驗結果。而在落點研究方面，實驗結果顯示，在相同流速下，直徑大小是主要影響分佈範圍的因素，且隨著流速的提高，落點的分布情況也會跟著較不集中。

In this research, we study the situation single sphere solid particle with rock surface in cross flows, and develop an approximate way to predict the position when the particles touch the bottom.
The rough spheres has higher drag than smooth spheres in cross flows, so in the process of calculation, we consider the gravity, buoyancy, added mass effect force and drag force to calculate the trajectory of single sphere solid particle with rock surface, and change the drag coefficient of smooth sphere to adjust the compute result. We found it can conform to the most results of experiment when 1.45 times of drag coefficient. The results shows that diameter is the important factor to the range of distribution in the same flow velocity and the situation of distribution become less concentration as the flow velocity becomes higher.

Brown Phillip P. and Lawler, Desmond F., Sphere Drag and
Settling Velocity Revisited. J. Envir. Engrg. Volume
129, Issue 3, pp. 222-231, 2003
Clift R., Grace J. R., and Weber. M. E., Bubbles, drops,
and particles. New York :Academic Press., 1978
Flemmer, R. L. C. and Banks, C. L., On the Drag
Coefficient of a Sphere. Powder., 48:P.217-221., 1986
Odar, F. and Hamilton, W.S., Forces on Sphere Accelerating
in a Viscous Fluid. Journal of Fluid Mechanics.,
18:2:P.302-314, 1964
Odar, F., Verification of the proposed equation for
calculation of the forces on a sphere accelerating in a
viscous fluid. Journal of Fluid Mechanics., 25:3:P.591-
592, 1966
Turton, R. and Levenspiel, O., A short Note on the Drag
Correlation for Spheres. Powder Tech., 47,:P.83-86., 1986
林永駿，圓球剛體三維沉降行為之研究國立台灣大學土木工程學研
究所博士論文，2000
蕭博元，水下沉埋管線搜尋與定位之研究，國立中山大學海洋
環境及工程研究所碩士論文，2005
國科會海洋學門海洋資料庫
http://www.ncor.ntu.edu.tw/ODBS/