Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 130021, China.
Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 130021, China.
Sci Total Environ. 2017 Dec 31;609:377-384. doi: 10.1016/j.scitotenv.2017.07.169. Epub 2017 Jul 25.
In this study, an improved laboratory two-dimensional airflow visualization device was developed for the quantitative analysis of airflow distribution at different heights from the sparger (20, 30, and 40cm) within the zone of influence (ZOI). The results indicated that the measured airflow rate distribution appeared Trapezium when the height was 20cm; however, the airflow rate matched a Gaussian distribution when the heights became 30cm and 40cm. The conical shape of the ZOI was observed in the experimental processes. The experimental results verified that the airflow distribution within the ZOI conformed to turbulent jet theory. According to turbulent jet theory, the distribution of the airflow rate changes from Trapezium to Gaussian, and the jet boundary mixed layer is a linear extension in the processes of jets. Through our study, it was found that this theory could be applied to airflow distribution and predictive models for the ZOI in air sparging remediation. The shape of the ZOI should be cone-like and the boundary layer of the ZOI is a linear extension in air sparging process. All the results from this study can provide theoretical support for the design and prediction of air sparging remediation for groundwater pollution.
在这项研究中，开发了一种改进的实验室二维气流可视化设备，用于定量分析影响区域（ZOI）内不同高度（20、30 和 40cm）的气流分布。结果表明，当高度为 20cm 时，测量的气流速率分布呈梯形；然而，当高度为 30cm 和 40cm 时，气流速率符合高斯分布。在实验过程中观察到 ZOI 的锥形形状。实验结果验证了 ZOI 内的气流分布符合湍流射流理论。根据湍流射流理论，气流速率的分布从梯形变为高斯，射流边界混合层在射流过程中是线性延伸的。通过我们的研究，发现该理论可应用于空气喷射修复中 ZOI 的气流分布和预测模型。ZOI 的形状应为锥形，ZOI 的边界层在空气喷射过程中是线性延伸的。本研究的所有结果都可为地下水污染空气喷射修复的设计和预测提供理论支持。
