Similarity Solution of Jet Boundary Layer for the Initial Segment of a Delta
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摘要: 三角洲初始段形成过程中,水流携带泥沙运动至湖区,主要依靠出射的初始动量来维持自身的继续运动.该文根据这一过程的运动特点,依据浑水浅水方程,建立了三角洲初始段平面射流边界层理论模式,采用相似解解法,得到了三角洲形成初期的流场分布.利用河床演变通用数学模型推导得到了表征入湖三角洲初始段形态特征的理论表达式,对三角洲初始段冲淤形态做了定量分析.通过实验验证,理论解能够较好地表达三角洲形成初期的冲淤趋势和形态特征.Abstract: Sediment is carried by flow to the lake area during the formation process of the initial segment of a delta, which mainly depends on the initial momentum to maintain its own continuous movement. According to the characteristics of this process, the theoretical model for the plane jet boundary layer in the initial segment of the delta was established based on the shallow water equations for muddy water, and the flow field distribution of the initial segment of delta formation was obtained with the similarity solution method. Based on the general mathematical model of river bed evolution, the theoretical expression of the morphological characteristics of the initial segment was derived, and the erosion and deposition of the initial segment were quantitatively analyzed. Through the experimental verification, the theoretical solution can well describe the erosion and deposition trend and morphological characteristics in the early stage of delta formation.
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Key words:
- delta /
- jet boundary layer /
- initial segment /
- erosion and deposition /
- similarity solution
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