高精度格式在河道水温模拟中的应用

水温是水环境质量评价的一项基本因素,准确的水温预测是许多水质模型的基础.水温变化过程可用对流扩散方程来描述,其模拟精度直接关系到水温模型的精度.结合交错网格,将高精度HAUC2格式应用到河道水温预测中,建立了一维河道水温模型,最后将模型应用于汉江皇庄--仙桃河段水温纵向输移扩散模拟中,取得良好的效果.

One-dimensional high-accuracy evaluation of the river water temperature

The present paper aims to introduce the author's experimental development and trial application of a new one-dimensional approach to the evaluation of the river water temperature. As is known, it is an essential element to evaluate the water environment, and therefore it is necessary to exactly predict the water temperature. Up to now, the researchers in this area have been paying great attention to the study of mathematical simulation as main models. The general practice is to use the convection-diffusion equation to control the water temperature changing process. Needless to say that the accuracy of the convection-diffusion equation simulation is related to the accuracy of simulation. Currently low order schemes are mainly adopted by many numerical models of water temperature. With the development of numerical simulation theory and the practical needs for more efficient simulation, higher order scheme proves to be more important in solving practical problems. Recently with the application of undetermined coefficient method, some higher order accuracy scheme named HAUC2 which is applied in the case of 1-D pure convection has been suggested. The present paper, applying HAUC2 scheme and staggered grid, has developed a new 1-D model for unsteady flow and water temperature simulation. The trial application of the new model in the middle reach from Hanjiang River, a tributary of the Yangtze River, that is, in the section of reach from Huangzhuang to Xiantao, has been done. The simulated result proves in conformity with the data observed. So the proposed model is expected to simulate the temperature process of natural rivers with higher accuracy.