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时段选取对大气负荷重力效应的影响分析
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作者 邓文彬 赵锐 +1 位作者 滕树琴 唐晓艳 《测绘科学》 CSCD 北大核心 2019年第5期32-36,共5页
针对当前重力观测数据处理中大气负荷效应改正的不确定性问题,该文提出一种分时段改正方法.通过采用不同时段观测数据,基于回归分析方法系统讨论时段选取对大气负荷重力效应改正的影响.利用高精度Wettzell台站超导重力观测数据进行实验... 针对当前重力观测数据处理中大气负荷效应改正的不确定性问题,该文提出一种分时段改正方法.通过采用不同时段观测数据,基于回归分析方法系统讨论时段选取对大气负荷重力效应改正的影响.利用高精度Wettzell台站超导重力观测数据进行实验分析.实验结果表明:采用不同时段观测数据,大气导纳值差异最大值约为-0.1μGal/hPa;采用不同时段的观测数据进行大气效应改正,其最大差异整体上可以达到2μGal.本文的研究可为精确计算大气负荷重力效应提供一定参考. 展开更多
关键词 重力 大气负荷 重力效应 时段 超导重力
光子芯片中类比引力的研究
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作者 盛冲 刘辉 祝世宁 《物理》 CAS 北大核心 2019年第7期409-416,共8页
探索和理解引力场弯曲时空的本质一直是人类孜孜不倦追求的目标。尤其最近天文学上两大事件:激光干涉引力波天文台探测到引力波信号以及事件视界望远镜拍到黑洞的影子,进一步激发人类对古老而神秘引力的兴趣。尽管人类在探测引力现象的... 探索和理解引力场弯曲时空的本质一直是人类孜孜不倦追求的目标。尤其最近天文学上两大事件:激光干涉引力波天文台探测到引力波信号以及事件视界望远镜拍到黑洞的影子,进一步激发人类对古老而神秘引力的兴趣。尽管人类在探测引力现象的天文实验技术上取得了巨大的进步,但是对于有些引力现象的研究仍然面临着挑战,特别是与引力有关的量子效应。另一方面,类比引力系统为人类研究引力效应提供了一个新的实验平台,它可以在实验室环境下研究目前天文观测仍面临挑战的引力现象,例如黑洞附近引力场的量子效应。文章将介绍以光子芯片作为一种类比引力的实验体系而实现的引力场弯曲时空的模拟与研究。 展开更多
关键词 引力 类比引力 光子芯片 弯曲时空
Formulation of Determining the Gravity Potential Difference Using Ultra-High Precise Clocks via Optical Fiber Frequency Transfer Technique
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作者 Ziyu Shen Wen-Bin Shen +3 位作者 Zhao Peng Tao Liu Shougang Zhang Dingbo Chao 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第2期422-428,共7页
Based on gravity frequency shift effect predicted by general relativity theory, this study discusses an approach for determining the gravity potential(geopotential) difference between arbitrary two points P and Q by r... Based on gravity frequency shift effect predicted by general relativity theory, this study discusses an approach for determining the gravity potential(geopotential) difference between arbitrary two points P and Q by remote comparison of two precise optical clocks via optical fiber frequency transfer. After synchronization, by measuring the signal’s frequency shift based upon the comparison of bidirectional frequency signals from P and Q oscillators connected with two optical atomic clocks via remote optical fiber frequency transfer technique, the geopotential difference between the two points could be determined, and its accuracy depends on the stabilities of the optical clocks and the frequency transfer comparison technique. Due to the fact that the present stability of optical clocks achieves 1.6×10-18 and the present frequency transfer comparison via optical fiber provides stabilities as high as 10-19 level, this approach is prospective to determine geopotential difference with an equivalent accuracy of 1.5 cm. In addition, since points P and Q are quite arbitrary, this approach may provide an alternative way to determine the geopotential over a continent, and prospective potential to unify a regional height datum system. 展开更多
关键词 GRAVITY FREQUENCY shift OPTICAL fiber FREQUENCY TRANSFER OPTICAL CLOCK GRAVITY potential
基于阈值约束的协克里金法联合反演重力与重力梯度数据 预览
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作者 高秀鹤 曾昭发 +1 位作者 孙思源 于平 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2019年第3期1037-1045,共9页
常规协克里金方法反演重力或重力梯度数据具有抗噪性好、加入先验信息容易等优点,其反演的地下密度分布能够识别异常体中心位置,还原异常体基本形态,但反演图像光滑,分辨率低,这是由于常规方法估计的密度协方差矩阵全局发散、平稳.为了... 常规协克里金方法反演重力或重力梯度数据具有抗噪性好、加入先验信息容易等优点,其反演的地下密度分布能够识别异常体中心位置,还原异常体基本形态,但反演图像光滑,分辨率低,这是由于常规方法估计的密度协方差矩阵全局发散、平稳.为了通过协克里金方法获得聚焦的密度分布需要改善密度协方差矩阵的性质.首先,本文推导了理论密度协方差公式,其性质表明,当理论模型聚焦分布时,其密度协方差矩阵是非平稳且聚焦分布的.为了打破常规协方差矩阵全局平稳、发散的特征,本文设置密度阈值处理协方差矩阵,通过不断更新协方差矩阵来迭代实现协克里金反演,最终得到相对聚焦的反演结果.用本文方法处理重力与重力梯度数据恢复两种密度模型,均得到了与正演模型匹配的反演结果;再将方法运用于文顿盐丘的实际测量重力与重力梯度数据,反演结果与已知的地质情况匹配较好. 展开更多
关键词 协克里金 联合反演 重力 重力梯度 阈值
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Accretion onto Charged Black Holes in Einstein and Massive Theories of Gravity
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作者 Abdul Jawad Shahid Chaudhary 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第6期702-710,共9页
The accretion process is being investigated onto some important black holes such as Born-Infeld-AdS black hole, non-linear charged black hole solution in AdS space-time and Einstein-Yang-Mills massive gravity in the p... The accretion process is being investigated onto some important black holes such as Born-Infeld-AdS black hole, non-linear charged black hole solution in AdS space-time and Einstein-Yang-Mills massive gravity in the presence of Born-Infeld nonlinear electrodynamics. We find out the relations of radial velocity, energy density and change of mass for mention black holes and analyze their behavior graphically for different values of equation of state parameters ω.We also examine the relations for critical speed for these black holes. It is observed that for different state parameters different fluids exhibit different evolutions in black holes backgrounds. The energy density of some fluids is negative or positive near the black hole while other fluids become cause to increase or decrease in black hole mass. 展开更多
关键词 ACCRETION black holes EINSTEIN GRAVITY MASSIVE GRAVITY
Forward Modeling Research of Gravity Data Offset in North China Region 预览
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作者 Dandan Li Xingong Tang +1 位作者 Shuai Hou Kui Xiang 《长江油气(英文版)》 2019年第2期79-88,共10页
Due to the complexity and overlap effects of gravity anomalies,the gravity high point always deviates from the real position of the target.Researching the offset characteristics is helpful to determine the right locat... Due to the complexity and overlap effects of gravity anomalies,the gravity high point always deviates from the real position of the target.Researching the offset characteristics is helpful to determine the right location of gravity anomalies.In this paper,a series of forward models were designed to calculate the offset features under different assumptions.Different density models were established based on the measured gravity data in north China Sunhu area and a variety of methods were tried to eliminate offset effects under different conditions.The results indicate that the gravity anomalies of different density bodies can be separated effectively and the real position of target can be correctly located by using the“layer stripping method”. 展开更多
关键词 GRAVITY Exploration GRAVITY OFFSET FORWARD Modeling Potential Field SEPARATION Digital Filter Layer STRIPPING Method
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Non-parametric reconstruction of growth index via Gaussian processes
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作者 Zhao-Yu Yin Hao Wei 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第9期110-119,共10页
The accelerated cosmic expansion could be due to dark energy within general relativity(GR), or modified gravity. Differentiating between them using both the expansion history and growth history has attracted considera... The accelerated cosmic expansion could be due to dark energy within general relativity(GR), or modified gravity. Differentiating between them using both the expansion history and growth history has attracted considerable attention. In the literature, the growth index γ has been found useful to distinguish these two scenarios. This work aims to consider the non-parametric reconstruction of the growth index γ as a function of redshift z from the latest observational data as of July 2018 via Gaussian processes. We found that f(R) theories and dark energy models within GR(especially ΛCDM) are inconsistent with the results in the moderate redshift range far beyond 3σ confidence level. A modified gravity scenario different from f(R) theories is favored. However, these results can also be due to other non-trivial possibilities in which dark energy models within GR(especially ΛCDM) and f(R) theories may still survive. In all cases, our results suggest that new physics is required. 展开更多
关键词 COSMOLOGY DARK energy modified GRAVITY growth index GAUSSIAN processes
惯性力本质探讨 预览
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作者 冯清亮 《辽宁师专学报:自然科学版》 2019年第1期4-6,87共4页
惯性力来源何方,至今仍是一个谜.通过分析地球引力、自由落体运动及惯性力三者的关系后,认为地球引力场与物体发生能量传输,其能量传输强度以力和加速度两种方式体现,二者随物体的加速运动状态此消彼长.当外力试图改变物体的加速运动状... 惯性力来源何方,至今仍是一个谜.通过分析地球引力、自由落体运动及惯性力三者的关系后,认为地球引力场与物体发生能量传输,其能量传输强度以力和加速度两种方式体现,二者随物体的加速运动状态此消彼长.当外力试图改变物体的加速运动状态时,必定遭到来自引力场的抵抗,此抵抗力既是引力,也是惯性力,只是二者起算点不同.惯性力、引力本质上都是引力场抵抗变化的结果. 展开更多
关键词 惯性 惯性力 惯性力本质 惯性质量 引力
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沙漏流动过程中重力变化现象 预览
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作者 荆世宏 李川南 +1 位作者 胡安平 寻之朋 《物理实验》 2019年第6期45-49,共5页
对沙子流动过程中沙漏重力变化现象进行了理论与实验研究.通过将重力变化过程分为6个阶段,对各阶段沙粒与沙漏作用过程进行详细理论分析,并且从沙漏孔径、沙子粒度、沙漏高度三方面进行了实验探究,得到以上3个因素对沙漏重力变化的影响.
关键词 沙漏 流动 重力
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Participation in the absolute gravity comparison with a compact cold atom gravimeter
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作者 付志杰 王启宇 +3 位作者 王兆英 吴彬 程冰 林强 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第1期52-57,共6页
The first Asia-Pacific Comparison of Absolute Gravimeters(APMP.M.G-K1) was organized by the National Institute of Metrology(NIM) of China from December 21, 2015 to March 25, 2016 in Changping, Beijing. Our compact col... The first Asia-Pacific Comparison of Absolute Gravimeters(APMP.M.G-K1) was organized by the National Institute of Metrology(NIM) of China from December 21, 2015 to March 25, 2016 in Changping, Beijing. Our compact cold atom gravimeter(CCAG) was transported from Hangzhou to Beijing with a long distance of about1200 km to participate in this comparison. The CCAG is the only one, to the best of our knowledge, that is based on the principle of atom interferometry among all the instruments. Absolute gravity in the indicated three test sites has been measured as requested by the organizer. The sensitivity of our CCAG is estimated to be90 μGal∕Hz p, even when the measurements are carried out without any vibration isolation. Besides, the accuracy of this gravimeter has been evaluated to be about 19 μGal by considering the significant system errors.Our results show a good agreement with the given reference value. 展开更多
关键词 PARTICIPATION ABSOLUTE gravity COMPARISON COMPACT cold ATOM GRAVIMETER
全文增补中
物化的光与重力——以特尔加诺住宅为例 预览
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作者 冯海辉 《城市建筑》 2019年第7期128-130,共3页
阿尔伯托·坎波·巴埃萨曾经提出过“物化的理念”的概念,文章尝试从建构的角度对“物化的理念”的概念进行解读。通过对巴埃萨的特尔加诺住宅的分析,解读光与重力这两个巴埃萨的建筑中的重要主题,是如何在设计中被物化,从而达... 阿尔伯托·坎波·巴埃萨曾经提出过“物化的理念”的概念,文章尝试从建构的角度对“物化的理念”的概念进行解读。通过对巴埃萨的特尔加诺住宅的分析,解读光与重力这两个巴埃萨的建筑中的重要主题,是如何在设计中被物化,从而达到塑造空间的目的。 展开更多
关键词 阿尔伯托·坎波·巴埃萨 建构 重力
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Behavior of Anisotropic Compact Stars in f(R, ?) Gravity
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作者 M.Farasat Shamir Adnan Malik 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第5期599-609,共11页
The aim of this paper is to investigate modified f(R, ?) theory of gravity, where R and ? represent the Ricci scalar and scalar potential respectively. Specifically, we take the spherically symmetric spacetime to disc... The aim of this paper is to investigate modified f(R, ?) theory of gravity, where R and ? represent the Ricci scalar and scalar potential respectively. Specifically, we take the spherically symmetric spacetime to discuss the possible emergence of compact stars. We study the physical behavior of compact stars by considering 4 U 1820-30, SAX J1808-3658 and Her X1, which are three popular models of compact stars. The graphical analysis of energy density, radial pressure, tangential pressure, energy conditions as well as stability of compact stars has been shown. It is concluded that behavior of these three stars is usual for f(R, ?) gravity models with some specific choices of model parameters. 展开更多
关键词 f(R ?) GRAVITY spherically symmetric SPACETIME compact STARS KLEIN-GORDON equation
重力对土体中地下结构地震反应的影响 预览
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作者 董正方 师成力 +1 位作者 王君杰 曾繁凯 《隧道建设(中英文)》 北大核心 2019年第4期576-583,共8页
为解决地震作用下土体重力与地下结构相互影响问题,首先,归纳重力对土体性质的影响规律,分析重力和地震反应的相互影响、地应力的处理和重力的施加方式等;然后,通过典型算例对重力施加方式的适用性、重力对地震反应的影响程度等进行评... 为解决地震作用下土体重力与地下结构相互影响问题,首先,归纳重力对土体性质的影响规律,分析重力和地震反应的相互影响、地应力的处理和重力的施加方式等;然后,通过典型算例对重力施加方式的适用性、重力对地震反应的影响程度等进行评价。结果表明:1)在地震作用下,地下结构的重力和地震反应相互影响;2)在进行数值计算时,重力可采用时程荷载的形式施加,并且宜保持重力加速度一直不变;3)当土体为非线性介质时,采用叠加原理进行计算存在误差,且叠加误差随着土体非线性程度的增加而增大,但并非单调增加,叠加误差还受地震波、场地等因素影响。 展开更多
关键词 地下结构 重力 地震反应 初始地应力 土体非线性
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Primordial perturbations and non-gaussianities in Horava-Lifshitz gravity
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作者 高显 《中国物理C:英文版》 SCIE CAS CSCD 2019年第7期118-126,共9页
We investigate primordial perturbations and non-gaussianities in the Horava-Lifshitz theory of gravitation.In the UV limit, the scalar perturbation in the Horava theory is naturally scale-invariant, ignoring the detai... We investigate primordial perturbations and non-gaussianities in the Horava-Lifshitz theory of gravitation.In the UV limit, the scalar perturbation in the Horava theory is naturally scale-invariant, ignoring the details of the expansion of the Universe. One may thus relax the exponential inflation and the slow-roll conditions for the inflaton field. As a result, it is possible that the primordial non-gaussianities, which are "slow-roll suppressed" in the standard scenarios, become large. We calculate the non-gaussianities from the bispectrum of the perturbation and find that the equilateral-type non-gaussianity is of the order of unity, while the local-type non-gaussianity remains small, as in the usual single-field slow-roll inflation model in general relativity. Our result is a new constraint on Horava-Lifshitz gravity. 展开更多
关键词 COSMOLOGICAL perturbation theory primordial NON-GAUSSIANITY Horava GRAVITY inflation
岩溶区煤矿工程堆积体边坡细沟发育及其水沙关系研究
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作者 林姿 史东梅 +3 位作者 娄义宝 蒋光毅 彭旭东 李叶鑫 《土壤学报》 CAS CSCD 北大核心 2019年第3期615-626,共12页
重力作用对坡面径流泥沙和细沟发育具有重要影响。以煤矿工程堆积体为研究对象,采用野外实地放水冲刷法研究不同坡度条件下,重力作用对工程堆积体边坡产流产沙细沟发育形态的影响。结果表明:(1)工程堆积体坡面侵蚀过程分为面蚀(产流3 mi... 重力作用对坡面径流泥沙和细沟发育具有重要影响。以煤矿工程堆积体为研究对象,采用野外实地放水冲刷法研究不同坡度条件下,重力作用对工程堆积体边坡产流产沙细沟发育形态的影响。结果表明:(1)工程堆积体坡面侵蚀过程分为面蚀(产流3 min内)和细沟侵蚀阶段,其中细沟侵蚀存在扩张(产流3~24 min)、过渡(产流24~30 min)和稳定(产流30 min后)3个发展过程,细沟最快出现为4s、最慢为97s,二者出现时间约相差24倍。(2)重力作用是影响工程堆积体边坡产流产沙及其波动性变化的重要原因,对工程堆积体边坡总产沙量贡献在17.41%以上,最高可达99.60%;初步判定,重力作用对边坡细沟发育影响作用明显的临界径流条件为20 L·min^-1,临界坡度条件为35°。(3)重力作用造成工程堆积体边坡细沟由短向长、由浅向深、由窄向宽发展,坡面细沟沟宽在7.89~19.73 cm之间,沟深在2.17~6.73 cm之间,宽深比在2.12~4.36之间,细沟密度在1.35~3.00m·m^-2之间;径流作用主导细沟深度发育,而重力作用主导细沟宽度发育;边坡细沟密度随放水流量及坡度增加呈先增大后减小的趋势。研究结果对于正确认识煤矿工程堆积体边坡产流产沙特征、影响因素及土壤侵蚀量测算具有重要参考意义。 展开更多
关键词 细沟发育 重力作用 水沙关系 工程堆积体 煤矿工程
Models of steam-assisted gravity drainage(SAGD) steam chamber expanding velocity in double horizontal wells and its application 预览
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作者 ZHOU You LU Teng +3 位作者 WU Shouya SHI Lanxiang DU Xuan WANG Junling 《石油勘探与开发:英文版》 2019年第2期347-354,共8页
The development of steam chamber can be used to evaluate steam-assisted gravity drainage(SAGD) performance. The velocity of steam chamber expanding is the key parameter for evaluating the development of steam chamber.... The development of steam chamber can be used to evaluate steam-assisted gravity drainage(SAGD) performance. The velocity of steam chamber expanding is the key parameter for evaluating the development of steam chamber. Based on SAGD technology theory and heat transfer theory, two calculation model methods, observation well temperature method and steam chamber edge method for estimating the horizontal expanding velocity of steam chamber, were presented. Through analyzing the monitoring data and numerical simulation results of a typical super heavy oil block developed by SAGD in Fengcheng oilfield in Xinjiang, NW China, the development patterns of steam chamber and temperature variation law in the observation well at different stages are determined. The observed temperature data was used to calculate steam chamber expanding velocity. The calculated chamber velocity at different time was applied to predict the temperature distribution of oil drainage zone at the edge of steam chamber and SAGD oil rate. The results indicate that temperature function of high temperature zone in the observation well temperature curve has a linear relationship with measuring depth.The characteristic section can be used to calculate key parameters such as the angle of the drainage interface, expanding edge and velocity of steam chamber. The field production data verify that the results of the two proposed methods of steam chamber growth are reliable and practical, which can provide theoretical support for the efficient development of SAGD. 展开更多
关键词 steam-assisted GRAVITY drainage observation well temperature STEAM CHAMBER STEAM CHAMBER EXPANDING VELOCITY oil drainage zone
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Simulated impacts of atmospheric gravity waves on the initiation and optical emissions of sprite halos in the mesosphere
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作者 Jinbo ZHANG Qilin ZHANG +2 位作者 Xiufeng GUO Wenhao HOU Haiyang GAO 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第4期631-642,共12页
The correlation between atmospheric gravity waves(GWs) and Transient Luminous Events(TLEs) has been poorly studied using both synchronous observations and numerical simulations. To investigate the modulation effects o... The correlation between atmospheric gravity waves(GWs) and Transient Luminous Events(TLEs) has been poorly studied using both synchronous observations and numerical simulations. To investigate the modulation effects of GWs on TLEs,a troposphere-mesosphere quasi-electrostatic field model is developed in three-dimensional Cartesian coordinates, and the effects of GW perturbations on the initiation and optical emissions of sprite halos are simulated using the model. Simulation results indicate that the atmospheric density at lower ionosphere altitudes becomes inhomogeneous due to GW perturbations, and sprite halos tend to initiate in the GW troughs due to the lower electric breakdown threshold. GW perturbations cause the deformation of sprite halos, strong luminous regions distribute mainly along the GW troughs while optical intensities along the GW peaks is relatively weak. Larger GW perturbations lead to more pronounced deformation of sprite halos, however, stronger lightning discharges in the troposphere result in less optical perturbations of sprite halos. The observed luminous intensities and optical morphology of sprite halos are also affected by the observing orientations and the lightning polarities. 展开更多
关键词 Three-dimensional quasi-electrostatic field model SPRITE HALOS Optical emission Gravity WAVES
东海盆地丽水凹陷断裂系统划分方法研究
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作者 江志强 明彦伯 姚刚 《地球物理学进展》 CSCD 北大核心 2019年第1期310-315,共6页
重力正则化倾斜角是断裂划分的常用方法,其为一阶水平与垂直导数的比值函数,计算结果极值对应于断裂的水平位置,该方法具有均衡不同深度构造幅值的优点,提高了对较深地质构造的识别能力.数据测量误差会造成正则化倾斜角结果出现局部干... 重力正则化倾斜角是断裂划分的常用方法,其为一阶水平与垂直导数的比值函数,计算结果极值对应于断裂的水平位置,该方法具有均衡不同深度构造幅值的优点,提高了对较深地质构造的识别能力.数据测量误差会造成正则化倾斜角结果出现局部干扰极值,且计算结果存在一定的发散,因此直接根据极值特征来判定断裂的存在性和准确位置存在困难.为了获得准确的东海盆地丽水凹陷的断裂分布,基于欧拉方程推导出正则化倾斜角与地质体位置参数对应的线性方程,并根据正则化倾斜角的分布特征制定相应的结果筛选准则来获得准确的构造位置.通过理论模型证明该方法所反演结果能准确地标识地质体范围,将其应用于东海盆地丽水凹陷的断裂划分,相对已有结果新划分出多条近东西走滑断裂,这与凹陷表现为南北分块的特征吻合,也验证了区域太平洋俯冲作用的影响,为下一步油气勘探方案提供了详实的基础资料. 展开更多
关键词 重力 正则化倾斜角 丽水凹陷 断裂 线性方程
Numerical modeling of lock-exchange gravity/turbidity currents by a high-order upwinding combined compact difference scheme 预览
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作者 Liang Zhao Ching-Hao Yu Zhiguo He 《国际泥沙研究:英文版》 SCIE 2019年第3期240-250,共11页
This study presents two-dimensional direct numerical simulations for sediment-laden current with higher density propagating forward through a lighter ambient water.The incompressible NavierStokes equations including t... This study presents two-dimensional direct numerical simulations for sediment-laden current with higher density propagating forward through a lighter ambient water.The incompressible NavierStokes equations including the buoyancy force for the density difference between the light and heavy fluids are solved by a finite difference scheme based on a structured mesh.The concentration transport equations are used to explore such rich transport phenomena as gravity and turbidity currents.Within the framework of an Upwinding Combined Compact finite Difference(UCCD)scheme,rigorous determination of weighting coefficients underlies the modified equation analysis and the minimization of the numerical modified wavenumber.This sixth-order UCCD scheme is implemented in a four-point grid stencil to approximate advection and diffusion terms in the concentration transport equations and the first-order derivative terms in the Navier-Stokes equations,which can greatly enhance convective stability and increase dispersive accuracy at the same time.The initial discontinuous concentration field is smoothed by solving a newly proposed Heaviside function to prevent numerical instabilities and unreasonable concentration values.A two-step projection method is then applied to obtain the velocity field.The numerical algorithm shows a satisfying ability to capture the generation,development,and dissipation of the Kelvin-Helmholz instabilities and turbulent billows at the interface between the current and the ambient fluid.The simulation results also are compared with the data in published literatures and good agreements are found to prove that the present numerical model can well reproduce the propagation,particle deposition,and mixing processes of lock-exchange gravity and turbidity currents. 展开更多
关键词 GRAVITY CURRENT TURBIDITY CURRENT Depth-resolving mathematical model INCOMPRESSIBLE Navier-Stokes equations Upwinding COMBINED Compact Difference(UCCD) scheme
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氢氧燃料电池电极中液态水的脱离时间研究 预览
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作者 程伟 余意 涂正凯 《武汉理工大学学报:交通科学与工程版》 2019年第4期652-656,共5页
水下潜航器用燃料电池的关键问题是水管理.利用液滴的重力来克服黏滞力可有效地实现液滴的自脱离,缓解燃料电池水淹机率.文中通过建立液态水在电极内的传输、涨大,以及脱离模型,研究不同的电极参数对液滴排出时间的影响.结果表明,液滴... 水下潜航器用燃料电池的关键问题是水管理.利用液滴的重力来克服黏滞力可有效地实现液滴的自脱离,缓解燃料电池水淹机率.文中通过建立液态水在电极内的传输、涨大,以及脱离模型,研究不同的电极参数对液滴排出时间的影响.结果表明,液滴在电极内的主要停留时间是涨大过程,电极表面液滴的疏水角度越大,临界半径越小,液滴成长的时间也就越长. 展开更多
关键词 质子交换膜燃料电池 水管理 重力 脱离时间
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