一个修改后的阻力系数模型,用于计算深海采矿中不规则的羽毛颗粒的终端沉降速度和水平扩散距离
Ze-Lin Liu1, Qiu-Hua Rao2, Wei Yi
1School of Civil Engineering, Central South University, Changsha, 410075, China.
概括
深海采矿风云威胁着海洋环境. 这项研究引入了粒子沉速度的新模型,改善了羽毛散布的预测,并帮助评估环境影响.
科学领域:
- 环境科学 环境科学
- 流体动力学 流体动力学
- 海洋学 海洋学 海洋学
背景情况:
- 深海采矿产生的羽毛,造成环境风险,由于海洋流.
- 准确预测羽毛散射范围对于环境影响评估至关重要.
- 现有的粒子沉速度模型往往对不规则粒子缺乏准确性,并且适用性有限.
研究的目的:
- 为不规则粒子开发一个修改后的阻力系数模型.
- 为了建立一个新的形状因子 (γ),考虑多维特征.
- 为预测水平扩散距离提出一个修改的高斯羽毛模型.
主要方法:
- 提出了一个新的形状因子 (γ),包括粒子厚度,预测面积和表面积.
- 使用新的形状因子开发了一个修改后的阻力系数 (CD) 模型.
- 验证了修改后的CD模型与广泛的雷诺兹数 (Re) 范围内的现有模型相比.
- 将沉积速度集成到修改的高斯羽毛模型中.
主要成果:
- 终端沉积速度 (wt) 随着新的形状因子 (γ),粒子直径 (dp) 和密度 (ρp) 的增加而增加.
- 与现有模型相比,修改后的CD模型表现出更高的准确性和更广泛的应用范围 (Re < 3×105).
- 更大的颗粒密度或直径会导致更高的沉速度和减少水平扩散.
结论:
- 开发的模型为不规则粒子的沉降速度提供了更准确的计算.
- 这项研究为预测深海采矿羽毛分散提供了理论基础.
- 改进的羽毛模型可以更好地评估和减轻深海采矿对环境的影响.
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