Bow wave and Hydraulic jump induced by cylindrical piers in open channel flows
碩士 === 國立中央大學 === 土木工程研究所 === 96 === Bow waves in front of cylindrical piers under different flow conditions, especially supercritical flows, are explored in this study by employing both flume experiments and 3D numerical simulation. An ultrasonic velocity profiler (UVP) is used to measure the downw...
Main Authors: | , |
---|---|
Other Authors: | |
Format: | Others |
Language: | zh-TW |
Published: |
2008
|
Online Access: | http://ndltd.ncl.edu.tw/handle/cjb9d7 |
Summary: | 碩士 === 國立中央大學 === 土木工程研究所 === 96 === Bow waves in front of cylindrical piers under different flow conditions, especially supercritical flows, are explored in this study by employing both flume experiments and 3D numerical simulation. An ultrasonic velocity profiler (UVP) is used to measure the downward/upward flow right in front of the pier, and the downward flow and the stagnation point along the profile are also measured. The magnitudes and the frequencies of bow waves are analyzed by image analysis. The vortex sizes are mainly determined by pier diameter alone. The dimensionless amplitude of bow waves is proportional to the square of upstream Froude numbers. The numerical simulations for piers in shallow water show that the shear stresses on the floor exhibit maximum value at the downstream sides, which is due to pier-induced surface drawdown and wake separation.
|
---|