A Frequency Domain Approach to Water Quality Modeling in Groundwater: Theory
A Frequency Domain Approach to Water Quality Modeling in Groundwater: Theory
复制标题
地下水水质建模的频域方法：理论
DOI：
10.1029/wr021i008p01175
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发表时间：
1985
影响因子：
5.4
通讯作者：
L. Gelhar
中科院分区：
文献类型：
--
作者：
C. Duffy;L. Gelhar
本文应用平稳随机过程的谱分析和线性滤波理论，研究了地下水环境示踪剂或污染时间序列复杂时间变化的分析方法。对时变源下溶质波动的解释是通过对三种广泛应用的输运模型的随机微分方程的频域解来完成的：（1）集总参数或线性水库模型;（2）曲线流场中的对流（平流）输运;和（3）均匀流场中的对流-弥散输运。频域解的理论传递函数和相位谱描述的振幅衰减和相位滞后之间的频率在输入和输出。三个模型的频率响应的比较表明，每个模型的独特的滤波特性可以提供一个诊断工具，用于将适当的理论与采样的水质“信号”相匹配。一个程序的参数估计，其中包括理论和现场估计的传递函数和相位谱的比较。
A method for the analysis of complex temporal variations of environmental tracers or pollution time series in groundwater is examined using spectral analysis and linear filter theory for stationary stochastic processes. The interpretation of solute fluctuations subject to a time varying source is accomplished via frequency domain solutions to stochastic differential equations for three widely applied transport models: (1) a lumped parameter or linear reservoir model; (2) convective (advective) transport in a curvilinear flow field; and (3) convective-dispersive transport in a uniform flow field. Frequency domain solutions are presented in terms of the theoretical transfer function and phase spectra which describe the amplitude attenuation and phase lag between frequencies in the input and output. A comparison of the frequency response of the three models indicates that the unique filtering characteristics of each may provide a diagnostic tool for matching the appropriate theory to a sampled water quality “signal.” A procedure is suggested for parameter estimation which involves comparison of the theoretical and field estimated transfer function and phase spectra.