This study presents a novel method for optimizing parameters in urban flood models,aiming to address the tedious and complex issues associated with parameter optimization.First,a coupled one-dimensional pipe network r...This study presents a novel method for optimizing parameters in urban flood models,aiming to address the tedious and complex issues associated with parameter optimization.First,a coupled one-dimensional pipe network runoff model and a two-dimensional surface runoff model were integrated to construct an interpretable urban flood model.Next,a principle for dividing urban hydrological response units was introduced,incorporating surface attribute features.The K-means algorithm was used to explore the clustering patterns of the uncertain parameters in the model,and an artificial neural network(ANN)was employed to identify the sensitive parameters.Finally,a genetic algorithm(GA) was used to calibrate the parameter thresholds of the sub-catchment units in different urban land-use zones within the flood model.The results demonstrate that the parameter optimization method based on K-means-ANN-GA achieved an average Nash-Sutcliffe efficiency coefficient(NSE) of 0.81.Compared to the ANN-GA and K-means-deep neural networks(DNN) methods,the proposed method better characterizes the runoff generation and flow processes.This study demonstrates the significant potential of combining machine learning techniques with physical knowledge in parameter optimization research for flood models.展开更多
The oil and gas potential of the Yan'an Formation in the Ordos Basin has yet to be fully tapped. In this study, the pore structure, mobile fluid saturation, and water flooding micro-mechanism of the Yan'an For...The oil and gas potential of the Yan'an Formation in the Ordos Basin has yet to be fully tapped. In this study, the pore structure, mobile fluid saturation, and water flooding micro-mechanism of the Yan'an Formation sandstone are systematically studied through the application of a series of rock physics and fluid experiments. The results show that there is a good positive correlation between porosity and permeability, and the reservoirs are divided into types Ⅰ, Ⅱ, and Ⅲ. Mercury injection tests show that the average pore throat radius of the oil-bearing reservoir ranges from 1 to 7 μm. The displacement pressure of the Yan'an Formation is also relatively low, and it decreases from 0.1 MPa to 0.01 MPa as the rock porosity increases from 11% to 18%. NMR tests show that small (diameter <0.5 μm) and medium pores (diameter ranging from 0.5 to 2.5 μm) are predominant in the reservoir. Different types of reservoirs have different characteristics of relative permeability curve. In addition, when the average oil recovery rate is less than 1 ml/min, the oil displacement efficiency increases faster. However, when the average oil recovery rate is between 1–3.5 ml/min, the oil displacement efficiency is maintained at around 27%–30%. Physical properties of the reservoir, pore-throat structure, experimental pressure difference, and pore volume injected — all have significant effects on oil displacement efficiency. For Type Ⅰ and Type Ⅱ reservoirs, the increase of the pore volume injected has a significant effect on oil displacement efficiency. However, for Type Ⅲ reservoirs, the change of pore volume injected has insignificant effect on oil displacement efficiency. This study provides a reference for the formulation of estimated ultimate recovery (EUR) measures for similar sandstone reservoirs.展开更多
低渗油藏孔隙结构复杂,比表面积大,空气泡沫驱过程中起泡剂在储层中吸附损失严重,影响空气泡沫驱的应用效果。延长东部油田甘谷驿油区孔隙度平均为10.76%,渗透率平均为0.933 m D,属于低孔特低渗储层。为了减小起泡剂在地层中的吸附,同...低渗油藏孔隙结构复杂,比表面积大,空气泡沫驱过程中起泡剂在储层中吸附损失严重,影响空气泡沫驱的应用效果。延长东部油田甘谷驿油区孔隙度平均为10.76%,渗透率平均为0.933 m D,属于低孔特低渗储层。为了减小起泡剂在地层中的吸附,同时提高泡沫液的稳定性,结合油藏实际地质特征,研制了一种基于脂肪醇聚氧乙烯醚-邻苯二甲酸酯钠盐的新型阴离子表面活性起泡剂,对新型起泡剂发泡能力、耐温耐盐性、吸附损失大小、耐油能力和界面张力等基本性能进行了系统评价。结果表明:在稳定性方面,当起泡剂含量大于2 000 mg/L时,发泡高度可超过180 mm,在2 000 mg/L、30℃时,新型起泡剂均优于SDS(十二烷基硫酸钠)和ABS(十二烷基苯磺酸钠)发泡性能;在遇油稳定性方面,加原油后起泡,原油加量为20%以内时对起泡结果仅有微弱干扰,起泡后加原油,当加入量为20%时,泡沫依然有较好的稳定性。新型起泡剂在遇油稳定性方面明显强于ABS和甘谷驿区块泡沫驱体系使用的BK6A起泡剂;在吸附损失方面,当油砂加量达到25 g时,起泡体积仅从620 m L降低至590 m L,吸附量少。新型起泡剂体系优越的发泡性能、稳泡性能和抗温抗盐性能,为泡沫驱油剂体系提供了重要的物质基础,不仅适合延长东部浅层特低渗油藏,同时也适应于延长西部中深层特低渗油藏。展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.42271483,42071364)the Postgraduate Research&Practice Innovation Program of Jiangsu Province (Grant No.KYCX23_1696).
文摘This study presents a novel method for optimizing parameters in urban flood models,aiming to address the tedious and complex issues associated with parameter optimization.First,a coupled one-dimensional pipe network runoff model and a two-dimensional surface runoff model were integrated to construct an interpretable urban flood model.Next,a principle for dividing urban hydrological response units was introduced,incorporating surface attribute features.The K-means algorithm was used to explore the clustering patterns of the uncertain parameters in the model,and an artificial neural network(ANN)was employed to identify the sensitive parameters.Finally,a genetic algorithm(GA) was used to calibrate the parameter thresholds of the sub-catchment units in different urban land-use zones within the flood model.The results demonstrate that the parameter optimization method based on K-means-ANN-GA achieved an average Nash-Sutcliffe efficiency coefficient(NSE) of 0.81.Compared to the ANN-GA and K-means-deep neural networks(DNN) methods,the proposed method better characterizes the runoff generation and flow processes.This study demonstrates the significant potential of combining machine learning techniques with physical knowledge in parameter optimization research for flood models.
基金supported by the Guiding Science and Technology Planning Project of Daqing(Grant No.zd-2021-36)Postdoctoral Scientific Research Developmental Fund of Heilongjiang Province,China(Grant No.LBH-Z21084)Natural Science Foundation of Heilongjiang Province(Grant No.LH 2022E019).
文摘The oil and gas potential of the Yan'an Formation in the Ordos Basin has yet to be fully tapped. In this study, the pore structure, mobile fluid saturation, and water flooding micro-mechanism of the Yan'an Formation sandstone are systematically studied through the application of a series of rock physics and fluid experiments. The results show that there is a good positive correlation between porosity and permeability, and the reservoirs are divided into types Ⅰ, Ⅱ, and Ⅲ. Mercury injection tests show that the average pore throat radius of the oil-bearing reservoir ranges from 1 to 7 μm. The displacement pressure of the Yan'an Formation is also relatively low, and it decreases from 0.1 MPa to 0.01 MPa as the rock porosity increases from 11% to 18%. NMR tests show that small (diameter <0.5 μm) and medium pores (diameter ranging from 0.5 to 2.5 μm) are predominant in the reservoir. Different types of reservoirs have different characteristics of relative permeability curve. In addition, when the average oil recovery rate is less than 1 ml/min, the oil displacement efficiency increases faster. However, when the average oil recovery rate is between 1–3.5 ml/min, the oil displacement efficiency is maintained at around 27%–30%. Physical properties of the reservoir, pore-throat structure, experimental pressure difference, and pore volume injected — all have significant effects on oil displacement efficiency. For Type Ⅰ and Type Ⅱ reservoirs, the increase of the pore volume injected has a significant effect on oil displacement efficiency. However, for Type Ⅲ reservoirs, the change of pore volume injected has insignificant effect on oil displacement efficiency. This study provides a reference for the formulation of estimated ultimate recovery (EUR) measures for similar sandstone reservoirs.
文摘低渗油藏孔隙结构复杂,比表面积大,空气泡沫驱过程中起泡剂在储层中吸附损失严重,影响空气泡沫驱的应用效果。延长东部油田甘谷驿油区孔隙度平均为10.76%,渗透率平均为0.933 m D,属于低孔特低渗储层。为了减小起泡剂在地层中的吸附,同时提高泡沫液的稳定性,结合油藏实际地质特征,研制了一种基于脂肪醇聚氧乙烯醚-邻苯二甲酸酯钠盐的新型阴离子表面活性起泡剂,对新型起泡剂发泡能力、耐温耐盐性、吸附损失大小、耐油能力和界面张力等基本性能进行了系统评价。结果表明:在稳定性方面,当起泡剂含量大于2 000 mg/L时,发泡高度可超过180 mm,在2 000 mg/L、30℃时,新型起泡剂均优于SDS(十二烷基硫酸钠)和ABS(十二烷基苯磺酸钠)发泡性能;在遇油稳定性方面,加原油后起泡,原油加量为20%以内时对起泡结果仅有微弱干扰,起泡后加原油,当加入量为20%时,泡沫依然有较好的稳定性。新型起泡剂在遇油稳定性方面明显强于ABS和甘谷驿区块泡沫驱体系使用的BK6A起泡剂;在吸附损失方面,当油砂加量达到25 g时,起泡体积仅从620 m L降低至590 m L,吸附量少。新型起泡剂体系优越的发泡性能、稳泡性能和抗温抗盐性能,为泡沫驱油剂体系提供了重要的物质基础,不仅适合延长东部浅层特低渗油藏,同时也适应于延长西部中深层特低渗油藏。
