Modeling of Contaminant Advection-Diffusion Process based on Hammerstein model
【摘要】：In this paper, the modeling of liquid contaminant fluid dynamics for the associated emission-diffusion process induced by environmental changes is investigated. Due to the contaminants and large fluid liquids interaction, the contaminant diffusion causes the concentration structure to be strong uncertainty. Parameters related to the contaminants concentration distribution,including the emission, concentration, and free flow speed are varied to investigate the characteristics of the contaminant diffusion flow. Motivated by the slowly time-varying properties of the contaminant emission diffusion process, recursive identification of Hammerstein structures is investigated to construct a model of liquid contaminant concentration diffusion process in the rivers flows. The unknown parameters in the model are estimated by using the given data and an algorithm is given for the choice of the appropriate number and type of autoregressive terms, changing trend terms, etc., in the model, which the models of the river flows is constructed by using daily and yearly data. The linear and nonlinear parameters are separated and estimated recursively in a parallel manner, with each updating algorithm using the most up-to-date estimation produced by the other algorithm at each time instant. Finally, the constructed model is tested from the environmental fluid dynamics data based on finite element method.