基于新形状因子的不规则形状的微塑料碎片的沉速度公式:二次运动的影响
Chaoqun Ji1, Jinfeng Zhang2, Guangwei Liu1
1State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation, Tianjin University, Tianjin 300072, China.
The Science of the total environment
|October 17, 2024
概括
预测微塑料 (MP) 碎片在水中的沉速度是了解它们的环境命运的关键. 使用不规则形状因子 (ISF) 的新公式为MP碎片提供了更准确的预测.
科学领域:
- 环境科学 环境科学
- 流体动力学 流体动力学
- 水域污染 水域污染
背景情况:
- 微塑料碎片是河流和湖泊中普遍存在的污染物.
- 准确预测微塑料沉速度对于了解它们在水生环境中的迁移和命运至关重要.
- 微塑料碎片的复杂几何和二次运动给预测它们的沉速度带来了挑战.
研究的目的:
- 开发一个数值模型并进行实验,以了解不规则的微塑料碎片的二次运动和沉积过程.
- 为了获得一个新的形状因子,适用于描述不规则的微塑料碎片.
- 建立一个明确的公式来预测不规则的微塑料碎片的沉积速度.
主要方法:
- 开发一个数值模型来模拟微塑料碎片的整个沉过程.
- 对数值模型的实验验证.
- 根据理论力分析,推导出新的不规则形状因子 (ISF).
- 拟合定位速度数据,开发一个新的预测公式,结合ISF.
主要成果:
- 数值模型揭示了微塑料碎片沉速度和方向的时间变化.
- 微塑料碎片根据速度波动被分为稳定,过渡和振荡的沉行为.
- 对于不规则的碎片,衍生的不规则形状因子 (ISF) 证明比Corey形状因子 (CSF) 更有效.
- 与现有方法和机器学习相比,采用ISF的拟议定位速度公式显示出更高的准确性.
结论:
- 这项研究更好地了解了影响微塑料碎片沉积的二次运动.
- 新的不规则形状因子 (ISF) 和衍生式为预测微塑料沉速度提供了更高的准确性.
- 这些发现有助于更有效的环境风险评估和微塑料污染管理策略.
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