Unified Standard of Sediment Incipient Motion and Corresponding Relationships Between Different Threshold Parameters Based on Probability Theory

基於概率理論的泥沙起動統一標準和起動參數間的量值對應

周雙(ZHOU SHUANG) ； 張根廣(ZHANG GENGUANG) ； 王愉樂(WANG YULE)

《台灣水利》 67卷3期 (2019/09) Pp. 16-23

摘要

Accurately calculating the incipient condition of sediment motion has been a challenge in hydraulic engineering for decades. The standards used to describe the critical condition of sediment incipient motion is not uniform, and the corresponding relationships between the incipient parameters cannot be developed. Based on the randomness of particle positions and the characteristics of flow pulsation, a method for calculating the total probability of the sediment threshold is proposed by solving the rolling equation. A formula for incipient velocity based on probability theory being derived, with the experimental data showing that the formula has good applicability. Based on the total probability, the corresponding relations between incipient parameters such as the number of incipient particles, the threshold velocity, the threshold shear stress, the bed load transport rates, and the threshold probability, are established under the same state.

關鍵字

Exposure angle ； Threshold velocity ； Shear stress ； Bed load transport

並列摘要

準確計算泥沙運動的臨界條件一直是水利工程中的一項挑戰。目前描述泥沙起動臨界狀態的標準尚不能達到統一，各起動參數之間尚不能達到量值對應。採用滾動起動模式，基於顆粒位置隨機性和水流脈動特性，提出全概率泥沙起動的計算方法，推導出一個基於全概率理論的起動流速公式。實測資料驗證表明，公式具有很好的適用性。在此基礎上，建立了同一起動狀態下，起動顆粒數、起動流速、起動切應力、輸沙率與起動概率等起動參數之間的量值對應關係。

並列關鍵字

暴露角 ； 起動流速 ； 切應力 ； 推移質輸沙