In oil and gas industry, mud-pulse telemetry has been widely used to obtain directional data, drilling parameters, formation evaluation data and safety data, etc. Generally, the drilling mud in most current models was...In oil and gas industry, mud-pulse telemetry has been widely used to obtain directional data, drilling parameters, formation evaluation data and safety data, etc. Generally, the drilling mud in most current models was considered to be a single-phase fluid through which the mud pulses travel, despite the fact that the drilling mud is composed of two or more phases. In this article, a multiphase flow formula was proposed to calculate the mud-pulse velocity as mud solids and free-gas content change, and a mathematical model was put forward to simulate the dynamic-transmission behavior of the mud-pressure pulse or waves. Compared to conventional methods, the present model provides more accurate mud-pulse attenuation, and the dynamic-transmission behavior of drilling-mud pulses along well bores can also be easily examined. The model is valuable in improving the existing mud-pulse systems and developing new drilling-mud pulse systems.展开更多
The horizontal migration of proppant was numerically investigated with a two-fluid model, in which the interaction between fracturing fluid and proppant, along with that among proppants was taken into account through ...The horizontal migration of proppant was numerically investigated with a two-fluid model, in which the interaction between fracturing fluid and proppant, along with that among proppants was taken into account through interphase forces. The migration process and the volumetric concentration of the proppant were examined under various conditions, and the averaged volumetric concentration of the proppant was obtained. The present research might be useful in the process design of the hydraulic fracturing in the oilfields.展开更多
基金Project supported by the National High Technology Research and Development Program of China (863 Program, Grant No. 820-Q-04).
文摘In oil and gas industry, mud-pulse telemetry has been widely used to obtain directional data, drilling parameters, formation evaluation data and safety data, etc. Generally, the drilling mud in most current models was considered to be a single-phase fluid through which the mud pulses travel, despite the fact that the drilling mud is composed of two or more phases. In this article, a multiphase flow formula was proposed to calculate the mud-pulse velocity as mud solids and free-gas content change, and a mathematical model was put forward to simulate the dynamic-transmission behavior of the mud-pressure pulse or waves. Compared to conventional methods, the present model provides more accurate mud-pulse attenuation, and the dynamic-transmission behavior of drilling-mud pulses along well bores can also be easily examined. The model is valuable in improving the existing mud-pulse systems and developing new drilling-mud pulse systems.
基金"Eleventh Five-Year Plan" of the Chinese Academy of Sciences (Grant No. KJCX2-YW-L02).
文摘The horizontal migration of proppant was numerically investigated with a two-fluid model, in which the interaction between fracturing fluid and proppant, along with that among proppants was taken into account through interphase forces. The migration process and the volumetric concentration of the proppant were examined under various conditions, and the averaged volumetric concentration of the proppant was obtained. The present research might be useful in the process design of the hydraulic fracturing in the oilfields.