Stochastic Analysis of Virus Transport in Aquifers

小行星9725086 拟议工作的目的是建立一个含水层病毒迁移的三维随机模型，并通过将其与现有的实地观察结果进行比较，评估该模型的实用性。 待检验的假设是，与其他当前可用的模型相比，随机光谱方法提供了对现场规模病毒运输的改进表示。 拟议工作的动机来自：（1）公共卫生需要预测浅层饮用水含水层中的病毒传播，因为有证据表明，许多水媒疾病的爆发可归因于来自陆地处置废物的非本地病毒病原体对供水威尔斯的污染，以及（2）缺乏适当的现有模型来表示在异质设置中的大尺度（数十至数百米）的病毒运输。 一个随机的方法需要确定性的计算，因为确定性地确定一个大尺度的非均质含水层结构是困难和不切实际的。 该模型将推导出使用光谱扰动分析，以评估当地规模的病毒传输现象与三维，相关的随机场模型的含水层渗透率耦合的效果。 结果将是一组平均微分方程，代表田间规模下游离病毒的运输和附着病毒的质量守恒。 预计平均方程将包括现场规模的平流、扩散、分离、过滤和吸附系数的数学表达式，这些系数取决于含水层的统计特性和当地规模的病毒迁移参数。 该理论将预测局部尺度过程和场尺度不均匀性之间的相互作用，以及这种相互作用对大规模病毒运输的重要性。 由此产生的模型可以简化，并适用于非生物胶体在地下水中的运动。

9725086 Welty The objective of the proposed work is to develop a three-dimensional stochastic model of virus transport in aquifers and to evaluate the usefulness of the model by comparing it to available field observations. The hypothesis to be tested is that the stochastic spectral approach provides an improved representation of field-scale virus transport compared to other currently available models. The motivation for the proposed work arises from: (1) the public health need to predict virus transport in shallow drinking water aquifers due to evidence that many waterborne disease outbreaks can be attributed to contamination of water supply wells by nonindigenous viral pathogens emanating from land-disposed wasters, and (2) the lack of appropriate existing models to represent virus transport at large scales (tens to hundreds of meters) in heterogeneous settings. A stochastic approach is needed over a deterministic computation because defining a heterogeneous aquifer structure deterministically for large scales is difficult and impractical. The model will be derived by using spectral perturbation analysis to evaluate the effect of coupling of local-scale virus transport phenomena with a three-dimensional, correlated-random-field model of aquifer permeability. The result will be a set of mean differential equations representing the transport of free viruses and conservation of mass of attached viruses at the field scale. It is expected that the mean equations will include mathematical expressions for field-scale advection, dispersion, detachment, filtration and adsorption coefficients that are dependent on aquifer statistical properties and local-scale virus transport parameters. The theory will predict the interaction between local-scale processes and field-scale heterogeneities and the importance of this interaction on large-scale virus transport. The resulting model could be simplified and applied also to the movement of abiotic colloids in groundwater.