关键词: 泥石流, 结构两相流, 模型

Abstract: 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.

Key words: debris flow, conceptual two phase flow, model measured data will be discussed in the companion paper.