- 期刊
三維度魚道水理及魚體行進力能之數值模擬研究
Numerical Investigation on Three-Dimensional Fishway Hydrodynamics and Fish Passage Energetics
摘要
本研究主要目的爲研析上溯運動方式與不同上溯的路徑之行進力能比較。研究之魚種爲粉紅鮭魚(pink salmon)，研究之魚道流場則使用三維度標準k-ε紊流模式計算模擬，搭配體積分率法來模擬具自由液面之二相流邊界條件，並再計算魚體在流場中逆流上溯所遭受之阻力與能量損耗。研究中先以Ead (2004)所試驗之魚道縮尺模型，來驗證三種不同魚道設計在水流經堰體之流況與水位，繼而規劃眞實尺寸之模式應用案例，本研究繼而藉由不同上溯路徑與上溯運動方式，透過魚體於水中力能之分析研究，並改良Weihs (2000)提出的海豚跳躍前進耗能計算方式，將跳躍運動應用至魚道流場內，以進行各種上溯案例間能量損耗之比較，由研究結果顯示，池堰式魚道模式應用案例中，同一魚種之最省能之路徑，爲魚體採跳躍上溯且近液面之路徑。
並列摘要
The main purpose of this study is to discuss the trajectories of the migrating fish (pink salmon) tracing back to upstream through pool-and-weir fishway, and compares the energetics for various migrating motions. A 3-D standard k-ε turbulent model together with the volume of fraction (VOF) method is used to solve fishway hydrodynamics. The simulated flow-field results are next employed to solve fishway hydrodynamics. The simulated flow-field results are next employed to estimate the force and energy acting on the fish body. The Numerical model is firstly verified by the reduced-scale experimental measurement of Ead et al. (2004). The numerical results are in good agreement with the experimental data in terms of water depths, flow velocities, and free surface profiles. A series of numerical scenario simulations are further conducted to simulated real-size fishways hydrodynamics. For the cases that fish is migrating in the pool-and-weir fishway, we modify the equations of dolphin dynamics (Weihs, 2000) to analyze the energy losses for various migrating motions. The simulated results show that the most economic fish energy passage in the pool-and-weir fishways is to take jump motion and to go through near the water surface.