Turbidity channels have been considered as one of the important types of deepwater reservoir, and the study of their architecture plays a key role in efficient development of an oil field. To better understand the res...Turbidity channels have been considered as one of the important types of deepwater reservoir, and the study of their architecture plays a key role in efficient development of an oil field. To better understand the reservoir architecture of the lower Congo Basin M oilfield, semiquantitative–quantitative study on turbidity channel depositional architecture patterns in the middle to lower slopes was conducted with the aid of abundant high quality materials（core, outcrop, logging and seismic data）,employing seismic stratigraphy, seismic sedimentology and sedimentary petrography methods. Then, its sedimentary evolution was analyzed accordingly. The results indicated that in the study area, grade 3 to grade 5 architecture units were single channel, complex channel and channel systems, respectively. Single channel sinuosity is negatively correlated with the slope, as internal grains became finer and thickness became thinner from bottom to top, axis to edge. The migration type of a single channel within one complex channel can be lateral migration and along paleocurrent migration horizontally, and lateral,indented and swing stacking in section view. Based on external morphological characteristics and boundaries,channel systems are comprised of a weakly confining type and a non-confining type. The O73 channel system can be divided into four complex channels named S1–S4, from bottom to top, with gradually less incision and more accretion. The study in this article will promote deeper understanding of turbidity channel theory, guide 3D geological modeling in reservoir development and contribute to efficient development of such reservoirs.展开更多
The demand for high-speed boats that operating near to shoreline is increasing nowadays.Understanding the behavior and attitude of high-speed boats when moving in different waterways is very important for boat designe...The demand for high-speed boats that operating near to shoreline is increasing nowadays.Understanding the behavior and attitude of high-speed boats when moving in different waterways is very important for boat designer.This research uses a CFD(Computational Fluid Dynamics)analysis to investigate the shallow water effects on prismatic planing hull.The turbulence fl ow around the hull was described by Reynolds Navier Stokes equations RANSE using the k-ɛturbulence model.The free surface was modelled by the volume of fl uid(VOF)method.The analysis is steady for all the ranges of speeds except those close to the critical speed range Fh=0.84 to 1.27 due to the propagation of the planing hull solitary waves at this range.In this study,the planing hull lift force,total resistance,and wave pattern for the range of subcritical speeds,critical speeds,and supercritical speeds have been calculated using CFD.The numerical results have been compared with experimental results.The dynamic pressure distribution on the planing hull and its wave pattern at critical speed in shallow water were compared with those in deep water.The numerical results give a good agreement with the experimental results whereas total average error equals 7%for numerical lift force,and 8%for numerical total resistance.The worst effect on the planing hull in shallow channels occurs at the critical speed range,where solitary wave formulates.展开更多
基金supported by the National Major Scientific and Technological Special Project during the Thirteenth Five-year Plan Period (2016ZX05033-003-002)the Project of Sinopec Science and Technology Development Department (G580015-ZS-KJB016)
文摘Turbidity channels have been considered as one of the important types of deepwater reservoir, and the study of their architecture plays a key role in efficient development of an oil field. To better understand the reservoir architecture of the lower Congo Basin M oilfield, semiquantitative–quantitative study on turbidity channel depositional architecture patterns in the middle to lower slopes was conducted with the aid of abundant high quality materials（core, outcrop, logging and seismic data）,employing seismic stratigraphy, seismic sedimentology and sedimentary petrography methods. Then, its sedimentary evolution was analyzed accordingly. The results indicated that in the study area, grade 3 to grade 5 architecture units were single channel, complex channel and channel systems, respectively. Single channel sinuosity is negatively correlated with the slope, as internal grains became finer and thickness became thinner from bottom to top, axis to edge. The migration type of a single channel within one complex channel can be lateral migration and along paleocurrent migration horizontally, and lateral,indented and swing stacking in section view. Based on external morphological characteristics and boundaries,channel systems are comprised of a weakly confining type and a non-confining type. The O73 channel system can be divided into four complex channels named S1–S4, from bottom to top, with gradually less incision and more accretion. The study in this article will promote deeper understanding of turbidity channel theory, guide 3D geological modeling in reservoir development and contribute to efficient development of such reservoirs.
文摘The demand for high-speed boats that operating near to shoreline is increasing nowadays.Understanding the behavior and attitude of high-speed boats when moving in different waterways is very important for boat designer.This research uses a CFD(Computational Fluid Dynamics)analysis to investigate the shallow water effects on prismatic planing hull.The turbulence fl ow around the hull was described by Reynolds Navier Stokes equations RANSE using the k-ɛturbulence model.The free surface was modelled by the volume of fl uid(VOF)method.The analysis is steady for all the ranges of speeds except those close to the critical speed range Fh=0.84 to 1.27 due to the propagation of the planing hull solitary waves at this range.In this study,the planing hull lift force,total resistance,and wave pattern for the range of subcritical speeds,critical speeds,and supercritical speeds have been calculated using CFD.The numerical results have been compared with experimental results.The dynamic pressure distribution on the planing hull and its wave pattern at critical speed in shallow water were compared with those in deep water.The numerical results give a good agreement with the experimental results whereas total average error equals 7%for numerical lift force,and 8%for numerical total resistance.The worst effect on the planing hull in shallow channels occurs at the critical speed range,where solitary wave formulates.
