The dynamic analysis of a pipe system is one of the most crucial problems for the entire mining system. A discrete element method （DEM） is proposed for the analysis of a deep-ocean mining pipe system, including the ...The dynamic analysis of a pipe system is one of the most crucial problems for the entire mining system. A discrete element method （DEM） is proposed for the analysis of a deep-ocean mining pipe system, including the lift pipe, pump, buffer and flexible hose. By the discrete element method, the pipe is divided into some rigid elements that are linked by flexible connectors. First, two examples representing static analysis and dynamic analysis respectively are given to show that the DEM model is feasible. Then the three-dimensional DEM model is used for dynamic analysis of the mining pipe system. The dynamic motions of the entire mining pipe system under different work conditions are discussed. Some suggestions are made for the actual operation of deep-ocean mining systems.展开更多
3D dynamic analysis models of 1000 m deep-ocean mining pipeline, including steel lift pipe, pump, buffer and flexible hose, were established by finite element method (FEM). The coupling effect of steel lift pipe and f...3D dynamic analysis models of 1000 m deep-ocean mining pipeline, including steel lift pipe, pump, buffer and flexible hose, were established by finite element method (FEM). The coupling effect of steel lift pipe and flexible hose, and main external loads of pipeline were considered in the models, such as gravity, buoyancy, hydrodynamic forces, internal and external fluid pressures, concentrated suspension buoyancy on the flexible hose, torsional moment and axial force induced by pump working. Some relevant FEM models and solution techniques were developed, according to various 3D transient behaviors of integrated deep-ocean mining pipeline, including towing motions of track-keeping operation and launch process of pipeline. Meanwhile, an experimental verification system in towing water tank that had similar characteristics of designed mining pipeline was developed to verify the accuracy of the FEM models and dynamic simulation. The experiment results show that the experimental records and simulation results of stress of pipe are coincided. Based on the further simulations of 1 000 m deep-ocean mining pipeline, the simulation results show that, to form configuration of a saddle shape, the total concentrated suspension buoyancy of flexible hose should be 95%?105% of the gravity of flexible hose in water, the first suspension point occupies 1/3 of the total buoyancy, and the second suspension point occupies 2/3 of the total buoyancy. When towing velocity of mining system is less than 0.5 m/s, the towing track of buffer is coincided with the setting route of ship on the whole and the configuration of flexible hose is also kept well.展开更多
A 3-D geometrical nonlinear model for the entire lift system of 1000-m sea trial system of China Ocean Mineral Resources R&D Association was established with finite element method.The model was utilized to analyze...A 3-D geometrical nonlinear model for the entire lift system of 1000-m sea trial system of China Ocean Mineral Resources R&D Association was established with finite element method.The model was utilized to analyze the dynamic characteristics of the vertical pipe under the influence of moving velocity,current direction and wave.The simulation results show that the axial stress is dominant on the vertical pipe,its maximum is located at the pipe top,all stresses are much less than the allowable value of the vertical pipe and joint;the heave motion leads to violent fluctuation of the force and stress,but a period of 8 s is not likely to resonate the present pipe;against the current,0.50 m/s is the suggested moving velocity of the ship and miner,while along the current,the moving velocity can be slightly higher than 0.75 m/s.展开更多
To make sure that the nodule collector can walk on the soft sediments of seafloor effectively, suspension principle of deep-ocean nodule collector is proposed. The supporting and driving mechanisms are separated to av...To make sure that the nodule collector can walk on the soft sediments of seafloor effectively, suspension principle of deep-ocean nodule collector is proposed. The supporting and driving mechanisms are separated to avoid collector sinking. The supporting mechanism is a streamlined body with large and smooth supporting area. The grounding pressure is reduced to 0.5- 1 N/cm2 to make sure that the sinkage is limited. The impellers serve as the driving mechanism to supply enough driving power. The position between the supporting mechanism and the driving mechanism can be adjusted according to the operating condition to decrease the walking resistance and to increase driving efficiency. The test results indicate that the collector can walk on the surface of the soft sediments with the limited sinkage. The traction forces were up to 800 kg and the sinkage of the impeller was under the limitation.展开更多
Independent of traditional approach of satellite altimeter calibration, the feasibility of altimeter validation using tide gauge located on solitary island at open sea (TGSI) and deep-ocean bottom pressure recorder (D...Independent of traditional approach of satellite altimeter calibration, the feasibility of altimeter validation using tide gauge located on solitary island at open sea (TGSI) and deep-ocean bottom pressure recorder (DBPR) separately is initially studied. Bias of Jason-3 sea surface height (SSH) and relative SSH bias (Δbias) between Jason-2 and Jason-3 is calculated using the data of tide gauge on Harvest oil platform, tide gauge No. 1890000 and DBPR No. 21419. The standard deviations of calculated SSH bias sequence are 3.98 cm, 2.87 cm and 8.61 cm respectively, and Δbias (Jason-3—Jason-2) is -3.62± 2.17 cm , -2.58±1.97 cm and -2.60±1.30 cm respectively. Comparing to the results reported by international calibration sites, the results show that Jason-3 SSH is 3.0 cm lower than that of Jason-2, the selected DBPR is appropriate to the calculation of relative SSH bias between Jason-2 and Jason-3, but it is not suitable for calibration or validation of single satellite, TGSI is appropriate to both.展开更多
本文利用2015年3月—2021年5月热带印度洋观测网(tropical Indian Ocean observation net,TIOON)在赤道80°E、85°E和93°E布设的观测潜标所获取的环流时间序列,结合BRAN2020(Bluelink Re ANalysis)环流流速数据以及JRA-55...本文利用2015年3月—2021年5月热带印度洋观测网(tropical Indian Ocean observation net,TIOON)在赤道80°E、85°E和93°E布设的观测潜标所获取的环流时间序列,结合BRAN2020(Bluelink Re ANalysis)环流流速数据以及JRA-55(Japanese 55-year Reanalysis)气象数据,研究了印度洋赤道深层环流(1200m以下)的季节内变化特征及其驱动机制。观测结果显示,深层环流流速平均值接近0,纬向流速标准偏差范围为2.5~3.1cm·s^(-1),经向流速标准偏差范围为2.6~3.1cm·s^(-1)。纬向流和经向流的季节内周期信号强度分别占各自总流动强度的88%~91%和74%~84%,揭示了深层环流中的显著季节内周期变率特征。小波分析表明,深层纬向流季节内信号主要周期为10~100d,其中80°E处的周期较长(50~90d),而93°E处的主要为50d及更高频信号,表现为蓝移现象,即环流变化的主导频率随位置靠东而变高的现象。经向流季节内信号以60d周期最显著。赤道风应力异常是深层环流季节内变率的重要驱动因素。中海盆(80°E和85°E)深层环流季节内变率主要受纬向风应力异常驱动,通过反射波动过程调制;基于低阶斜压模态,能量通过Kelvin波在东边界反射后形成的Rossby波向深层传递。东海盆(93°E)深层环流季节内变率主要受纬向和经向风应力异常驱动,通过直接波动过程调制;基于多阶斜压模态,能量通过在环流西侧由风直接驱动产生的Yanai波向深层传递。根据线性波动理论,本研究刻画了上述赤道波的能量传播射线,结果显示地形对赤道波调制深海环流的动力过程有重要影响:中海盆的平坦地形有利于向下向西传播能量的反射波动过程,而90°E海脊可能会阻碍向下向东传播能量的直接波动过程。在平坦地形区域,正压不稳定过程在经向上无显著差异且强度弱,区域平均结果显示能量主要由平均流向环流季节内变率释放;90°E海脊附近,环流季节内变率与平均流之间存在更强的非线性动力作用,表现为环流季节内变率向平均流转移能量。本研究加深了对深层环流动力学的理解,为改进深海环流模拟提供了观测依据。展开更多
在遥感海浪数据质量控制研究中,由于数据的复杂与不规则性,传统质量控制方法对海浪数据单点异常值的检测具有一定局限性。深度学习具有强大的特征学习能力,在解决非线性复杂问题方面具有一定优势,将其应用在数据质量控制领域可以提高异...在遥感海浪数据质量控制研究中,由于数据的复杂与不规则性,传统质量控制方法对海浪数据单点异常值的检测具有一定局限性。深度学习具有强大的特征学习能力,在解决非线性复杂问题方面具有一定优势,将其应用在数据质量控制领域可以提高异常值检测能力。本研究采用遥感海浪有效波高数据,构建双向长短期记忆网络(bi-directional long short term memory,Bi-LSTM)模型对有效波高进行预测,结合阈值方法进行异常检测,与3σ准则法、孤立森林模型法、 LSTM模型法以及VAE-LSTM模型法进行异常检测精度比较,探究基于Bi-LSTM的质量控制模型在遥感海浪数据异常值检测方面的能力。试验结果表明,Bi-LSTM质量控制模型具有良好的异常值检测效果,其精准率、召回率、 F1分数和运行时间分别为91%、 93%、 92和3.35 s,综合评价效果最佳,可有效对遥感海浪数据进行质量控制。展开更多
垂直混合参数化是海洋环流模拟中的主要不确定性来源。近年来,深度学习因其刻画复杂非线性过程的能力,逐渐用于改进传统参数化方案。本文基于Fang et al.(2025)提出的深度学习垂直混合参数化方案(DLVMP),借助Python与Fortran混合编程技...垂直混合参数化是海洋环流模拟中的主要不确定性来源。近年来,深度学习因其刻画复杂非线性过程的能力,逐渐用于改进传统参数化方案。本文基于Fang et al.(2025)提出的深度学习垂直混合参数化方案(DLVMP),借助Python与Fortran混合编程技术,将其嵌入大气物理研究所发展的气候系统海洋模式(LICOM),设计了参照试验[CNTR,采用Canuto et al.(2001)混合参数化方案]、K-Profile-Parameterization(KPP)混合参数化方案试验与DLVMP敏感性试验并开展长期气候模拟。结果表明,DLVMP方案整体继承了KPP的偏差特征,但因引入赤道观测数据,对赤道次表层海温气候态模拟有所改进;与Canuto et al.(2001)方案相比,DLVMP与KPP普遍低估表层混合强度、高估次表层混合强度,致使三组试验在海温、盐度、混合层深度、大西洋经圈翻转流(AMOC)和副热带环流(Subtropical Cell,STC)等方面存在显著差异;表层混合强度的低估削弱了中纬度通风过程,导致DLVMP试验中STC结构上移,强度增强,并在温跃层以下引起显著的海温冷偏差。本研究揭示了深度学习参数化方案在实际应用中面临训练集规模和质量的双重挑战,为后续改进提供了关键方向。展开更多
基金This researchis part of a project financially supported by the National Natural Science Goundation of China(GrantNo.50275152)National Deep-Sea Technology Project of Development and Research.(Grant No.DY105-3-2-2)
文摘The dynamic analysis of a pipe system is one of the most crucial problems for the entire mining system. A discrete element method （DEM） is proposed for the analysis of a deep-ocean mining pipe system, including the lift pipe, pump, buffer and flexible hose. By the discrete element method, the pipe is divided into some rigid elements that are linked by flexible connectors. First, two examples representing static analysis and dynamic analysis respectively are given to show that the DEM model is feasible. Then the three-dimensional DEM model is used for dynamic analysis of the mining pipe system. The dynamic motions of the entire mining pipe system under different work conditions are discussed. Some suggestions are made for the actual operation of deep-ocean mining systems.
基金Project(DY105-3-2-2) supported by China Ocean Mineral Resources Research and Development Association(COMRA)Project(50675226) supported by the National Natural Science Foundation of China
文摘3D dynamic analysis models of 1000 m deep-ocean mining pipeline, including steel lift pipe, pump, buffer and flexible hose, were established by finite element method (FEM). The coupling effect of steel lift pipe and flexible hose, and main external loads of pipeline were considered in the models, such as gravity, buoyancy, hydrodynamic forces, internal and external fluid pressures, concentrated suspension buoyancy on the flexible hose, torsional moment and axial force induced by pump working. Some relevant FEM models and solution techniques were developed, according to various 3D transient behaviors of integrated deep-ocean mining pipeline, including towing motions of track-keeping operation and launch process of pipeline. Meanwhile, an experimental verification system in towing water tank that had similar characteristics of designed mining pipeline was developed to verify the accuracy of the FEM models and dynamic simulation. The experiment results show that the experimental records and simulation results of stress of pipe are coincided. Based on the further simulations of 1 000 m deep-ocean mining pipeline, the simulation results show that, to form configuration of a saddle shape, the total concentrated suspension buoyancy of flexible hose should be 95%?105% of the gravity of flexible hose in water, the first suspension point occupies 1/3 of the total buoyancy, and the second suspension point occupies 2/3 of the total buoyancy. When towing velocity of mining system is less than 0.5 m/s, the towing track of buffer is coincided with the setting route of ship on the whole and the configuration of flexible hose is also kept well.
基金Project (DY105-03-02-02) supported by the Deep-Ocean Technology Development Item of China
文摘A 3-D geometrical nonlinear model for the entire lift system of 1000-m sea trial system of China Ocean Mineral Resources R&D Association was established with finite element method.The model was utilized to analyze the dynamic characteristics of the vertical pipe under the influence of moving velocity,current direction and wave.The simulation results show that the axial stress is dominant on the vertical pipe,its maximum is located at the pipe top,all stresses are much less than the allowable value of the vertical pipe and joint;the heave motion leads to violent fluctuation of the force and stress,but a period of 8 s is not likely to resonate the present pipe;against the current,0.50 m/s is the suggested moving velocity of the ship and miner,while along the current,the moving velocity can be slightly higher than 0.75 m/s.
基金Project(2012AA091201) supported by the National High Technology Research and Development Program of China
文摘To make sure that the nodule collector can walk on the soft sediments of seafloor effectively, suspension principle of deep-ocean nodule collector is proposed. The supporting and driving mechanisms are separated to avoid collector sinking. The supporting mechanism is a streamlined body with large and smooth supporting area. The grounding pressure is reduced to 0.5- 1 N/cm2 to make sure that the sinkage is limited. The impellers serve as the driving mechanism to supply enough driving power. The position between the supporting mechanism and the driving mechanism can be adjusted according to the operating condition to decrease the walking resistance and to increase driving efficiency. The test results indicate that the collector can walk on the surface of the soft sediments with the limited sinkage. The traction forces were up to 800 kg and the sinkage of the impeller was under the limitation.
基金National Natural Science Foundation of China(No.41774018,41674082)Foundation of State Key Laboratory of Geo-information Engineering(No.SKLGIE2018-ZZ-4)。
文摘Independent of traditional approach of satellite altimeter calibration, the feasibility of altimeter validation using tide gauge located on solitary island at open sea (TGSI) and deep-ocean bottom pressure recorder (DBPR) separately is initially studied. Bias of Jason-3 sea surface height (SSH) and relative SSH bias (Δbias) between Jason-2 and Jason-3 is calculated using the data of tide gauge on Harvest oil platform, tide gauge No. 1890000 and DBPR No. 21419. The standard deviations of calculated SSH bias sequence are 3.98 cm, 2.87 cm and 8.61 cm respectively, and Δbias (Jason-3—Jason-2) is -3.62± 2.17 cm , -2.58±1.97 cm and -2.60±1.30 cm respectively. Comparing to the results reported by international calibration sites, the results show that Jason-3 SSH is 3.0 cm lower than that of Jason-2, the selected DBPR is appropriate to the calculation of relative SSH bias between Jason-2 and Jason-3, but it is not suitable for calibration or validation of single satellite, TGSI is appropriate to both.
文摘本文利用2015年3月—2021年5月热带印度洋观测网(tropical Indian Ocean observation net,TIOON)在赤道80°E、85°E和93°E布设的观测潜标所获取的环流时间序列,结合BRAN2020(Bluelink Re ANalysis)环流流速数据以及JRA-55(Japanese 55-year Reanalysis)气象数据,研究了印度洋赤道深层环流(1200m以下)的季节内变化特征及其驱动机制。观测结果显示,深层环流流速平均值接近0,纬向流速标准偏差范围为2.5~3.1cm·s^(-1),经向流速标准偏差范围为2.6~3.1cm·s^(-1)。纬向流和经向流的季节内周期信号强度分别占各自总流动强度的88%~91%和74%~84%,揭示了深层环流中的显著季节内周期变率特征。小波分析表明,深层纬向流季节内信号主要周期为10~100d,其中80°E处的周期较长(50~90d),而93°E处的主要为50d及更高频信号,表现为蓝移现象,即环流变化的主导频率随位置靠东而变高的现象。经向流季节内信号以60d周期最显著。赤道风应力异常是深层环流季节内变率的重要驱动因素。中海盆(80°E和85°E)深层环流季节内变率主要受纬向风应力异常驱动,通过反射波动过程调制;基于低阶斜压模态,能量通过Kelvin波在东边界反射后形成的Rossby波向深层传递。东海盆(93°E)深层环流季节内变率主要受纬向和经向风应力异常驱动,通过直接波动过程调制;基于多阶斜压模态,能量通过在环流西侧由风直接驱动产生的Yanai波向深层传递。根据线性波动理论,本研究刻画了上述赤道波的能量传播射线,结果显示地形对赤道波调制深海环流的动力过程有重要影响:中海盆的平坦地形有利于向下向西传播能量的反射波动过程,而90°E海脊可能会阻碍向下向东传播能量的直接波动过程。在平坦地形区域,正压不稳定过程在经向上无显著差异且强度弱,区域平均结果显示能量主要由平均流向环流季节内变率释放;90°E海脊附近,环流季节内变率与平均流之间存在更强的非线性动力作用,表现为环流季节内变率向平均流转移能量。本研究加深了对深层环流动力学的理解,为改进深海环流模拟提供了观测依据。
文摘在遥感海浪数据质量控制研究中,由于数据的复杂与不规则性,传统质量控制方法对海浪数据单点异常值的检测具有一定局限性。深度学习具有强大的特征学习能力,在解决非线性复杂问题方面具有一定优势,将其应用在数据质量控制领域可以提高异常值检测能力。本研究采用遥感海浪有效波高数据,构建双向长短期记忆网络(bi-directional long short term memory,Bi-LSTM)模型对有效波高进行预测,结合阈值方法进行异常检测,与3σ准则法、孤立森林模型法、 LSTM模型法以及VAE-LSTM模型法进行异常检测精度比较,探究基于Bi-LSTM的质量控制模型在遥感海浪数据异常值检测方面的能力。试验结果表明,Bi-LSTM质量控制模型具有良好的异常值检测效果,其精准率、召回率、 F1分数和运行时间分别为91%、 93%、 92和3.35 s,综合评价效果最佳,可有效对遥感海浪数据进行质量控制。
文摘垂直混合参数化是海洋环流模拟中的主要不确定性来源。近年来,深度学习因其刻画复杂非线性过程的能力,逐渐用于改进传统参数化方案。本文基于Fang et al.(2025)提出的深度学习垂直混合参数化方案(DLVMP),借助Python与Fortran混合编程技术,将其嵌入大气物理研究所发展的气候系统海洋模式(LICOM),设计了参照试验[CNTR,采用Canuto et al.(2001)混合参数化方案]、K-Profile-Parameterization(KPP)混合参数化方案试验与DLVMP敏感性试验并开展长期气候模拟。结果表明,DLVMP方案整体继承了KPP的偏差特征,但因引入赤道观测数据,对赤道次表层海温气候态模拟有所改进;与Canuto et al.(2001)方案相比,DLVMP与KPP普遍低估表层混合强度、高估次表层混合强度,致使三组试验在海温、盐度、混合层深度、大西洋经圈翻转流(AMOC)和副热带环流(Subtropical Cell,STC)等方面存在显著差异;表层混合强度的低估削弱了中纬度通风过程,导致DLVMP试验中STC结构上移,强度增强,并在温跃层以下引起显著的海温冷偏差。本研究揭示了深度学习参数化方案在实际应用中面临训练集规模和质量的双重挑战,为后续改进提供了关键方向。
