High-pressure shallow(gas/water)flow is often hidden in the deepwater seabed,so penetrating shallowflow in drilling without BOP will be highly risky.In this case,the conventional well killing method to balance the for...High-pressure shallow(gas/water)flow is often hidden in the deepwater seabed,so penetrating shallowflow in drilling without BOP will be highly risky.In this case,the conventional well killing method to balance the formation pressure with back pressure generated by well head equipment is no longer suitable.Based on the analysis of structural characteristics of domestic and foreign multi-phase mixing systems,a ZM-2 drillingfluid density adjustment mixing device with independent intellectual property right was developed according to the principles of dy-namic well killing.The device is mainly composed of a throttle valve,a high-precision electromagneticflowmeter,a mixer,dumbbell-shaped nozzles,connecting pipes and other components.Fixed on the mixer are three inlets tofill heavy mud,seawater and additives.Opposed jetting is adopted to realize rapid and uniform mixing offluids with different densities.A laboratory test was conducted to work out the relationship between throttle opening and injectionflow rate and establish a linear relationship between killingfluid density and heavy mudflow.The results offield test conducted in the Nanhai No.8 drill ship showed that the mixing device was stable in operation and excellent in mixing performance.The density difference of ingredient mixture could be controlled within 0.05 g/cm3 after the mixtureflowed out of the mixing chamber of the mixer of about 0.3 m long,so such high precision can meet the requirement of dynamic well killing.展开更多
A simplified simulation method based on the FDTD technique that can handle active devices is proposed. This method well suits the electrical crosstalk analysis of multi-channel integrated, opto-electronic mixed module...A simplified simulation method based on the FDTD technique that can handle active devices is proposed. This method well suits the electrical crosstalk analysis of multi-channel integrated, opto-electronic mixed modules. We apply this method to an 8-channel integrated super-compact high-sensitivity optical module. The results show good agreement between simulations and measurements.展开更多
文摘High-pressure shallow(gas/water)flow is often hidden in the deepwater seabed,so penetrating shallowflow in drilling without BOP will be highly risky.In this case,the conventional well killing method to balance the formation pressure with back pressure generated by well head equipment is no longer suitable.Based on the analysis of structural characteristics of domestic and foreign multi-phase mixing systems,a ZM-2 drillingfluid density adjustment mixing device with independent intellectual property right was developed according to the principles of dy-namic well killing.The device is mainly composed of a throttle valve,a high-precision electromagneticflowmeter,a mixer,dumbbell-shaped nozzles,connecting pipes and other components.Fixed on the mixer are three inlets tofill heavy mud,seawater and additives.Opposed jetting is adopted to realize rapid and uniform mixing offluids with different densities.A laboratory test was conducted to work out the relationship between throttle opening and injectionflow rate and establish a linear relationship between killingfluid density and heavy mudflow.The results offield test conducted in the Nanhai No.8 drill ship showed that the mixing device was stable in operation and excellent in mixing performance.The density difference of ingredient mixture could be controlled within 0.05 g/cm3 after the mixtureflowed out of the mixing chamber of the mixer of about 0.3 m long,so such high precision can meet the requirement of dynamic well killing.
文摘A simplified simulation method based on the FDTD technique that can handle active devices is proposed. This method well suits the electrical crosstalk analysis of multi-channel integrated, opto-electronic mixed modules. We apply this method to an 8-channel integrated super-compact high-sensitivity optical module. The results show good agreement between simulations and measurements.
