Interpolation In The Numerical Calculation Of Two-dimensional Water Quality Model

The finite element method dealing with two-dimensional complex water quality models is widely applied to predict the numerical values of the water pollutants such as BOD,.COD of complex river sections. According to the flowing belts and different sections, the river can be divided into several grids by the finite element method. The complicated water quality model could be simplified by means of calculating the subtle changes in every element, therefore, the water condition of the required section could be predicted by the results.Considering the principle of finite element method, t1he grids must be selected as many as possible for the sake of accurate prediction. As a result, lots of data should be dealt with simult'~ieous1y. Usually, the flowing belt's shape could be obtained by reading the date from the graph of accumulating flow volume, and then the result of prediction could be gained by the use of FORTRAN language. However, the traditional method often leads to a low accuracy because of the enormous calculation and systematic errors during the data acquirement.The paper utilized MATLAB language, which is especially suitable for matrix calculation, to deal with large data in application of finite element method. It could not only simplify the calculation, but also avoid some systematic errors by the replacement of INTERPOLATOR with DRAWING GRAPH. Consequently, more precise result and economic cost of manpower and material resources could be produced.The Algorithm, which uses MATLAB to solve the two-dimensional river simulation problems, provided a new tool for the finite element method, and it also exerts a high practical value in the research of two-dimensional water quality models and the environment impact assessments.