数字模拟自由和沉浸式液压跳跃在梯形和三角形宏观度上的数值模拟
Harshit Kumar Jayant1, Bharat Jhamnani1
1Delhi Technological University, Department of Civil Engineering, Delhi 110042, India.
Heliyon
|December 11, 2023
概括
这项研究使用三角形和梯形宏粗度改进了液压跳跃特性. 三角形的宏细度被证明比梯形更有效地优化开放通道流程中的自由和沉浸式液压跳跃.
科学领域:
- 流体力学 流体力学 流体力学
- 开放通道的流量.
- 液压工程 液压工程 液压工程
背景情况:
- 液压跳跃在开放通道流和液压工程中至关重要.
- 床上的宏观硬度元素可以修改液压跳跃特性.
研究的目的:
- 为了研究三角形和梯形宏粗度对自由和潜水液压跳跃的影响.
- 为了比较三角形与梯形宏观硬度元素的性能.
主要方法:
- 使用计算流体动力学 (CFD) 数值模型.
- 分析了液压跳跃特征,包括连续深度比,尾水深度比,速度概况和动动能.
- 将CFD结果与实验结果进行比较以进行验证.
主要成果:
- 对于特定的弗劳德数,三角形宏敏度表现出优于梯形宏敏度的性能.
- 这两种宏观硬度类型在自由跳跃和潜水跳跃中,与光滑床相比,显著减少了滚筒长度.
- 与实验数据相比,CFD模型的平均误差在6%以内,证实了它的可靠性.
结论:
- 宏观粗度,特别是三角形元素,可以有效地增强液压跳跃特性.
- 经过验证的CFD模型是分析和预测工程应用中的液压跳动行为的可靠工具.
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