An irradiance profile measurement approach and profiling system were developed to measure the solar irradiance profile of the Arctic sea ice using fiber optic spectrometry.The approach involved using a miniature spect...An irradiance profile measurement approach and profiling system were developed to measure the solar irradiance profile of the Arctic sea ice using fiber optic spectrometry.The approach involved using a miniature spectrometer to sense light signals collected and transmitted from a fiber probe.The fiber probe was small,and could thus move freely in inclined bore holes drilled in sea ice with its optical entrance pointing upward.The input-output relationship of the system was analyzed and built.Influence factors that determined the system output were analyzed.A correctional system output approach was proposed to correct the influence of these factors,and to obtain the solar irradiance profile based on the measurements outputted by this system.The overall performance of the system was examined in two ice floes in the Arctic during the 9th Chinese National Arctic Research Expedition.The measured solar irradiance profiles were in good agreement with those obtained using other commercially available oceanographic radiometers.The derived apparent optical properties of sea ice were comparable to those of similar sea ice measured by other optical instruments.展开更多
With a clear understanding of the drilling fluid techniques and the cutting taking mechanism, a new advanced model is set up for analyzing field data and quantitative forecast of cutting taking mechanism. Therefore,...With a clear understanding of the drilling fluid techniques and the cutting taking mechanism, a new advanced model is set up for analyzing field data and quantitative forecast of cutting taking mechanism. Therefore, a number of values affecting the drilling rate and the hole cleaning are studied over a wide range of parameters. Drilling data obtained under high borehole pressure conditions are analyzed to determine the causes of the reduction in rate of penetration (ROP) as the borehole pressure increases, which in some cases is caused by the buildup of rock debris under the bit. The theoretical achievement and testing conclusions can be very instructional for horizontal well drilling. Much higher annular velocities are required for effective hole cleaning in directional wells than in vertical wells. High viscosity muds are observed to provide better transport than low viscosity muds.展开更多
基金The National Natural Science Foundation of China under contract No.41976218the Joint Zhoushan City and Zhejiang University Cooperation Project under contract No.2019C81034+1 种基金the National Key Research and Development Program of China under contract No.2016YFC1400303the Program for Zhejiang Leading Team of S&T Innovation under contract No.2010R50036.
文摘An irradiance profile measurement approach and profiling system were developed to measure the solar irradiance profile of the Arctic sea ice using fiber optic spectrometry.The approach involved using a miniature spectrometer to sense light signals collected and transmitted from a fiber probe.The fiber probe was small,and could thus move freely in inclined bore holes drilled in sea ice with its optical entrance pointing upward.The input-output relationship of the system was analyzed and built.Influence factors that determined the system output were analyzed.A correctional system output approach was proposed to correct the influence of these factors,and to obtain the solar irradiance profile based on the measurements outputted by this system.The overall performance of the system was examined in two ice floes in the Arctic during the 9th Chinese National Arctic Research Expedition.The measured solar irradiance profiles were in good agreement with those obtained using other commercially available oceanographic radiometers.The derived apparent optical properties of sea ice were comparable to those of similar sea ice measured by other optical instruments.
文摘With a clear understanding of the drilling fluid techniques and the cutting taking mechanism, a new advanced model is set up for analyzing field data and quantitative forecast of cutting taking mechanism. Therefore, a number of values affecting the drilling rate and the hole cleaning are studied over a wide range of parameters. Drilling data obtained under high borehole pressure conditions are analyzed to determine the causes of the reduction in rate of penetration (ROP) as the borehole pressure increases, which in some cases is caused by the buildup of rock debris under the bit. The theoretical achievement and testing conclusions can be very instructional for horizontal well drilling. Much higher annular velocities are required for effective hole cleaning in directional wells than in vertical wells. High viscosity muds are observed to provide better transport than low viscosity muds.
