In view of seepage process in vertical fracture well in low permeability reservoir,considering kickoff pressure gradient and media deformation coefficient,bilinear flow model is established.

Based on the two-ray model for land mobile communication,a new two-ray model which is suitable for the low-orbit satellite communication is presented and the relation of space attenuation with the satellite elevation is deduced in this paper.

By considering the air-ground radio communication channel as a "two-ray model",the PDF of the received signal envelope,represented with the average power and the Rice factor,is developed.

Considering factors as two-phase of oil and water,production history,areal heterogeneity of the reservoir,well-bore storativity and skin,we establish a mathematical well testing model with polymer flooding in producing period and a streamline model for unsteady well testing.

We have developed a three dimensional (3D) compositional mathematical model for two phase (oil and water) flow and derived a new 3D streamline model with capillarity and gravity effects.

Integrated two-fluid model for laminar bubbly flow;

The flow characteristic of gas-solid bubbling fluidized-bed was simulated based on two-fluid model by using Fluent.

Based on the granules kinetics,an Euler-Euler two-fluid model was established for studying the flow patterns of liquid-solid two-phase flow in the tubular loop reactor.