泥石流的结构两相流模型:I.理论

CONCEPTUAL TWO PHASE FLOW MODEL OF DEBRIS FLOW: Ⅰ. THEORY

泥石流的运动既有类似于固液两相流之处，又在很大程度上不同于固液两相流。在泥石流宾汉体模型、膨胀体模型、粘塑体模型及颗粒流模型研究的基础上，本文提出一种新的模型——泥石流的“结构两相流模型”。这种模型具有以往各类模型的优点，同时又便于对不同类型的泥石流进行描述。在理论上，它比现行各类模式更加严密；在应用上，它较现行各类模式更加方便，能够适用于更加广泛的各类条件。泥石流的结构两相流模型可将现行模型作为特例而高度概括，从概念上也容易理解。

On the basis of classification of various kinds of debris flows with the emphases of their dynamic behaviours in relation to the corresponding constitutive relations, a conceptual two phase flow model of debris flow is developed in the present paper. The model is well structured by defining the conceptual liquid phase which is the slurry actually composed of water and cohesional fine sediment particles and behaves as non Newtonian fluid, as well as the conceptual solid phase which is composed of the particles with their diameters larger than certain critical size. Basic equations for both phases are given based on the concept of solid liquid two phase flow theory, but the differences between the debris flow and the two phase flow in common sense are fully considered, which is just the “Conceptual” means. With the generalized model presented, the complex motion of debris flow can be reasonably described, and simple flows such as muddy flow and water rock flow can be included as special cases, under which the model can be greatly simplified. In consideration that the successful application of kinetic theory of gas molecules to the granular flow, analogy between the conceptual solid phase in debris flow and the gas molecules is made. Furthermore, greater details are given for water rock flows, including both saturated flows and non saturated flows. The model presented herein will result in the exact solution of water rock flows under the condition of 1 D steady uniform flow. Thus, various special characteristics of water rock flow may be revealed correspondingly. The application of the model in connection with the