适应实验方法,在不同的床材配置和带有和没有的斜坡下判断液压系数
Ayalkie Belete Amsie1, Abebe Temesgen Ayalew2, Zerihun Makayno Mada2
1Water Resources Research Center, Arba Minch University, Ethiopia.
Heliyon
|July 1, 2024
概括
这项研究发现,具有随机配置的20mm颗粒大小的石床是开放通道流动的最佳选择,在处理高排放和提高液压效率方面,其性能优于较大的颗粒和垂直设置.
科学领域:
- 液压工程 液压工程 液压工程
- 开放通道的流量
- 流体力学 流体力学 流体力学
背景情况:
- 准确的液压参数估计对于高效的开放通道流量系统设计至关重要.
- 粗聚合物床的配置和粒度大小显著影响流动阻力和放电特性.
- 像矩形堤这样的结构的存在进一步复杂化了流动动力学,需要仔细分析.
研究的目的:
- 在随机和垂直配置下评估粗聚合物床的液压系数和参数.
- 为了确定不同床位条件的矩形堤的排放系数.
- 调查粗度和液压参数之间的关系,并验证理论方程.
主要方法:
- 在使用20mm和30mm床材的12米长方形管道中进行实验室实验.
- 分析了分析数据的粒子大小分布,并进行了大约1680次测试.
- 测量了曼宁的粗度系数和排放系数在不同的床倾斜,配置,和/或没有矩形.
主要成果:
- 曼宁的粗度系数通常更高,随着堤的存在,随着谷粒大小和床的配置而变化.
- 矩形的排放系数差异很大,受粒径 (20mm vs. 30mm) 和床的配置 (随机 vs.垂直) 的影响.
- 更粗的颗粒 (30mm) 增加了粗度系数,降低了放电和速度;对于高放电,选择随机的20mm床.
结论:
- 随机配置的20mm颗粒大小床对于开放通道的流量优越,特别是对于高排放,与垂直配置或30mm床相比.
- 该研究强调了床的粗度,粒度大小和配置对液压性能的影响.
- 由于可能的设计不准确性,仅仅依赖于像曼宁的"n"这样的恒定摩擦因子是不建议的;建议采用考虑床特性的细微方法.
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