A novel model is established to predict the temperature field in horizontal wellbore during CO2 fracturing. The pressure work and viscous dissipation are considered, transient energy, mass momentum equations as well physical properties solved fully coupled. passes convergence test verified through a comparison using COMSOL software. Then, sensitivity analysis performed study effects of treating...

water conveyance through pumping takes a lot of energy and cost and therefore, its application should be accompanied by exact design of pumping station as well as correct positions of pumps and their subsidiary apparatus. sumps are designed for many pumping stations and often face the problems of vortex and irregular flows. therefore an investigation of the general flow pattern in sumps in diff...

Complex two-phase flow phenomena in wellbores after sour gas kick may lead to severe well control incidents. By bridging the solubility, H2S phase transition and equations, a model is established under conditions of transient non-isothermal states wellbores, which validated against experimental data. The following conclusions are drawn article: (1) higher dissolved quantity larger density invad...

Expedition 309, “Superfast Spreading Rate Crust 2,” successfully deepened Hole 1256D (6.736°N, 91.934°W) by 503 m to a total depth of 1255.1 meters below seafloor (mbsf) or 1005.1 meters subbasement. The average rate of core recovery for the expedition was 36%. Much higher rates of recovery were experienced in the lowermost section of the hole (~70% average below 1200 mbsf). At the end of Exped...

An optical system based on the confocal principle has been developed for real-time precision measurements of the depth of micro-holes during the laser drilling process. The capability of the measuring system is theoretically predicted by the Gaussian lens formula and experimentally validated to achieve a sensitivity of 0.5 μm. A nanosecond laser system was used to drill holes, and the hole dept...

In this paper we determine the ability to obtain values of the first normal stress difference, N1, at relative high shear rates (1.0–100.0 s−1) in slit-die for several polymer melts of varying degrees of fluid elasticity using hole pressure data and the Higashitani–Pritchard–Baird (PHB) quation. Accurate measurements of the hole pressure, Ph, which is defined as the difference between the press...

How to effectively transfer and exert a pressure on drills in lateral drilling, and to raise the efficiency of rock-breaking and rate of penetration in a bid, is the key technology to improve the quality, speed and economic benefits of lateral drilling. Therefore, based on high pressure jet of 16-hole and 7-hole nozzles, which are suitable for lateral drilling in oilfield at the present stage, ...