underbalanced drilling as multiphase flow is done in oil drilling operation in low pressure reservoir or highly depleted mature reservoir. correct determination of the pressure loss of three phase fluids in drilling annulus is essential in determination of hydraulic horsepower requirements during drilling operations. in this paper the pressure loss of solid-gas-liquid three-phase fluids flow in...

Several experiments have been developed around a bidirectional island-driven chart parser. The system follows basically the approach of Stock, Satta and Corazza, and the experiments have been designed and performed with the purpose of examining several ways of improvement: basic strategyt of the algorithm (pure island-driven vs mixed island-driven/bottom-up approaches), strategies for extending...

Traditional companies used to be authoritarian and built around hierarchical organizational charts. Facing more dynamic environments in recent history, many companies experimented with newer forms of organization, usually cutting down long decision paths and fostering lean structures able to react to rapid changes in the marketplace. One crucial difference between both types of organizations is...

the simultaneous flow of oil and water in porous media is described by relative permeability curves, mainly derived from laboratory experiments. relative permeability is of paramount importance in predicting reservoir production performance and drive mechanisms and its value depends largely on the volume fraction of fluids present in the test samples. nowadays x-ray scanners are one of the most...

Petroleum resources are found within sedimentary rocks that have a sufficient interconnected void space to store and transmit fluids. The actual flow of liquid and gas phases occurs on a micrometer scale in the void space between rock grains. On the other hand, the hydrocarbon is typically carried in rock zones that are a few tens of meters thick but extend several kilometers in the lateral dir...

For the characteristics of horizontal fractures in shallow low-permeability oil layers after hydraulic fracturing in multilayer reservoirs, horizontal fractures are taken equivalent to an elliptical cylinder with the reservoir thickness using the equivalent permeability model; then, upon the elliptic seepage theory, the seepage field which has led by a vertical well with horizontal fractures is...