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NUMERICAL STUDY OF NON-AQUEOUS PHASE LIQUID TRANSPORT IN A SINGLE FILLED FRACTURE BY LATTICE BOLTZMANN METHOD

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Journal of Hydrodynamics 2012年第1期24卷 130-137页

作者： DOU zhi zhou zhi-fang HUANG Yong WU Wei School of Earth Science and Engineering Hohai UniversityNanjing 210098China School of Materials Science and Engineering Southeast UniversityNanjing 211189China

In this article,the Non-Aqueous Phase Liquid（NAPL）transport in the single filled fracture was studied with the Shan-Chen multi-component multiphase Lattice Boltzmann Method（LBM）with special consideration of wettability *** the help of the model,the contact angle of the non-wetting phase and wetting phase interface at a solid wall could be *** considering a set of appropriate boundary conditions,the fractured conductivity was investigated in condition that the NAPL blocks the channels in the single filled *** order to study the wettability effects on the NAPL transport,a constant driving force was introduced in the Shan-Chen multi-component multiphase *** regimes with different wettabilities were *** results show that the LBM is a very instrumental method for simulating and studying the immiscible multiphase flow problems in single filled fracture.

关键词： single filled fracture Lattice Boltzmann Method(LBM) Non-Aqueous Phase Liquid(NAPL)transport wettability contact angle immiscible two-phase flow

THE NATURAL CONVECTION OF AQUIFERS WITH CONSTANT HEAT SOURCES AND ITS INFLUENCE ON TEMPERATURE FIELDS

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Journal of Hydrodynamics 2012年第4期24卷 617-627页

作者： LIU Guo-qing zhou zhi-fang School of Earth Science and Engineering Hohai UniversityNanjing 210098China

By combining sand tank tests with numerical simulations, this paper studies the temperature fields around constant heat sources to reveal the mechanism of the natural convection and its influence on the temperature fields in the process of energy storage. Using the ＂24-channel temperature auto acquisition system＂ developed by our research group in the tests, the temperatures are recorded at measuring points within the research area in the tests, the revised Brinkman equation and a transfer-convection balance model are used for solving the aquifer water-thermal coupling problems, and through comparison of the test results with the calcula- tion results, it is discovered that the influence ranges and the variations of the two temperature fields are consistent, which validates the mathematical model. On the basis of this, we also study the influences of the heat source positions and the boundary conditions on the temperature fields, and the results show that, under the natural convection, the heat source positions may influence the distri- bution of the temperature fields, thus affect the energy storage. For the same energy storage layer, the temperature field for the top energy storage is characterized by a smaller heat influence range and a relatively concentrated temperature distribution. However, when the heat source is at the bottom, the range of a temperature field, and the temperature is relatively dispersed, which is not favorable to heat recycle, with the same heat source position, the boundary conditions determine the size of the critical Rayleigh number, and thus have an influence on the occurrence and the strength of the natural convection, and accordingly, on the temperature fields.

关键词： porous media natural convection water-thermal coupling sand tank test numerical simulation

SIMULATION OF SOLUTE TRANSPORT IN A PARALLEL SINGLE FRACTURE WITH LBM/MMP MIXED METHOD

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Journal of Hydrodynamics 2008年第3期20卷 365-372页

作者： TAN Ye-fei zhou zhi-fang College of Civil Engineering Hohai University NanJing 210098 China

This article deals with the solute transport in a single fracture with the combination of the Lattice Boltzmann Method （LBM） and Modified Moment Propagation （MMP） method, and this mixed method is proved to have several advantages over the LBM and Moment Propagation （MP） mixed method which leads to negative concentrations under some conditions in computation. The disadvantage of LBM/MP has been overcome to a certain extent. Also, this work presents an LBM solution of modeling single fractures with uniformly or randomly distributed grains, which can provide a new path of applying the LBM in solute transport simulation in fractures.

关键词： Lattice Boltzmann Method (LBM) Modified Moment Propagation (MMP) method LBM/MMP mixed method single fracture solute transport rough fracture

ANALYTICAL SOLUTION OF GROUNDWATER FLUCTUATIONS IN ESTUARINE AQUIFER

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Journal of Hydrodynamics 2005年第5期17卷 641-646页

作者： CHEN Jing zhou zhi-fang JIA Suo-bao College of Civil Engineering Hohai University Nanjing 210098 China Hydrology and Water Resources Investigation Bureau of Jiangsu Province Nanjing 210029 China

As a basic factor in the environment of estuary, tidal effects in the coastal aquifer have recently attracted much attention because tidal dynamic also greatly influences the solute transport in the coastal aquifer. Previous studies on tidal dynamic of coastal aquifers have focused on the inland propagation of oceanic tides in the cross-shore direction, a configuration that is essentially one-dimensional. Two-dimensional analytical solutions for groundwater level fluctuation in recent papers are localized in presenting the effect of both oceanic tides and estuarine tides in quadrantal aquifer. A two-dimensional model of groundwater fluctuations in estuarine zone in proposed in this paper. Using complex transform, the two-dimensional flow equation subject to periodic boundary condition is changed into time-independent elliptic problem. Based on Green function method, an analytical solution for groundwater fluctuations in fan-shaped aquifer is derived. The response to of groundwater tidal loading in an estuary and ocean is discussed. The result show that its more extensive application than recent studies.

关键词： coastal aquifer analytical solution fanshaped area groundwater fluctuations Green function method estuary environment

A FIELD TEST DATA RESEARCH BASED ON A NEW HYDRAULIC PARAMETERS QUICK TEST TECHNOLOGY

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Journal of Hydrodynamics 2010年第4期22卷 562-571页

作者： ZHAO Yan-rong zhou zhi-fang School of Earth Sciences and Engineering Hohai University Nanjing 210098 China

The hydraulic parameter quick test system in accordance with the oscillation principle can overcome the shortcomings of traditional methods in determining hydraulic parameters which,besides having complex hydrogeological restrictions and needing complex equipment in the field,are often both time and energy consuming,and high *** on the hydrogeological conditions in the north anchorage of Taizhou Yangtze River Highway Bridge,a quick hierarchical test is carried out for different depths of single-hole drilling to verify the function of the system in this ***,with a purification of the raw data gathered in the test by wavelet denoising,the hydraulic parameters are worked out by adopting the Kipp model.A comparison between the Kipp model results and stratigraphic data as well as pumping test results justifies the reliability and accuracy of the new *** study finds other advantages of the method like high efficiency in operation,flexibility in stratified test,as well as ***,the technology is of significant practical value and application prospect.

关键词： hydraulic parameters oscillation principle slug test field test wavelet denoising

LABORATORY EXPERIMENTS ON SOLUTE TRANSPORT IN A PARTIAL TRANSFIXION SINGLE FRACTURE

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Journal of Hydrodynamics 2011年第5期23卷 570-579页

作者： CAI Jin-long zhou zhi-fang HUANG Yong School of Earth Science and Engineering Hohai University Nanjing 210098 China

In the study of solute transport in rough single fracture, the contact area is an important factor. The single fracture is defined as two categories in this article： the full transfixion single fracture and the partial transfixion single fracture. The purpose of this article is to research how the contact area affects the solute transport in partial transfixion single fracture. The contact area is generalized as square blocks with three sizes, and contact rate is variable, a series of experiments for solute transport were conducted in a simulation model which can simulate the two types of fractures in the laboratory. Based on the analysis of the breakthrough curves and the experiment phenomena, it is concluded that the difference of breakthrough curves of various contact rates is evident and increases with the increase of contact rate, the relative error curves reflect the difference of block sizes, and the maximum errors increase from smaller than 0.2 to about 0.8 with the increase of contact rate. These phenomena are also explained qualitatively in this article. It is concluded that the contact area strongly affects solute transport, and the research of channels formed by contact area is useful to further understand the rule of solute transport in partial transfixion single fracture.

关键词： contact rate channels partial transfixion single fracture solute transport

SOLUTE TRANSPORT IN NATURAL FRACTURES BASED ON DIGITAL IMAGE TECHNOLOGY

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Journal of Hydrodynamics 2009年第2期21卷 219-227页

作者： TAN Ye-fei zhou zhi-fang HUANG Yong College of Civil Engineering Hohai University Nanjing 210098 China The Department of Geoscience College of Science University of Nevada Las Vegas 89154 USA

A method of fracture boundary extraction was developed using the Gaussian template and Canny boundary detection on the basis of the collected digital images of natural fractures. The roughness and apertures of the fractures were briefly discussed from the point of view of digital image analysis. The extracted fractured image was translated into a lattice image which can be directly used in numerical simulation. The lattice Boltzmann and modified moment propagation mixed method was then applied to the simulation of solute transport in a natural single fracture, and this mixed method could take the advantages of the lattice Boltzmann method in dealing with complex physical boundaries. The obtained concentrations was fitted with the CXTFIT2.1 code and compared with the results obtained with the commercial software Feflow. The comparison indicates that the simulation using the mixed method is sound.

关键词： fracture solute transport digital image transaction boundary detection lattice Boltzmann method modified moment propagation method

Vadose-zone moisture dynamics under radiation boundary conditions during a drying process

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Journal of Hydrodynamics 2014年第5期26卷 734-744页

作者：韩江波周志芳傅志敏王锦国 School of Earth Sciences and Engineering Hohai University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute College of Hydrology and Water Resources Hohai University

In order to better understand the soil moisture dynamics during a drying process, a soil column experiment is conducted in the laboratory, followed by the numerical modeling with consideration of the coupled liquid water, water vapor and heat transport in the vadose zone. Results show that there are three distinct subzones above the water table according to the temporally dynamic variation of the water content profiles. Zone 1 sees a decrease in the water contents in the upper profiles （0 m-0.05 m） due to a negative net water flux in this zone where the upward isothermal water vapor flux becomes the main flow mechanism in the soils. Irl contrast, the water content within Zone 2 in the depth ranging from 0.05 m to 0.37 m sees an apparent increase over the, resulting from the positive net thermal water-vapor and isothermal liquid-water fluxes into this layer. Zone 3 （0.37 m-0.65 m） also sees an apparent decrease in the water content since the isothermal liquid water flux carries the liquid water either upward out of this region for vaporization or downward to the water table as a recharge to the groundwater.

关键词： moisture dynamics soil water flux vadose zone soil column experiment soil drying

Loss of heterozygosity on long arm of chromosome 22 in sporadic colorectal carcinoma

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World Journal of Gastroenterology 2002年第4期8卷 668-673页

作者： Chong-zhi zhou zhi-Hai Peng fang Zhang Guo-Qiang Qiu Department of General Surgery,Shanghai First People Hospital,Shanghai 200080,China Lin He Shanghai Institutes for Biological Science,Chinese Academy of Science,Shanghai 200031,China Department of General Surgery Shanghai First People Hospital 85 Wujin Road Shanghai 200080 China.

AIM: The loss of heterozygosity (LOH) on tumorsuppressor genes is believed to play a key role incarcinogenesis of colorectal cancer, In this study, weanalyzed the LOH at 5 loci on the long arm ofchromosome 22 in sporadic colorectal cancer to identifyadditional loci involved in colorectal ***: Five polymorphic microsatellite markerswere analyzed in 83 cases of colorectal and normal DNAby PCR. PCR products were eletrophoresed on an ABI377 DNA sequencer; Genescan 3.1 and Genotype 2.1software were used for LOH scanning and analysisComparison between LOH frequency andclinicopathological data were performed by x2 test. P＜0.05 was considered as statistically ***: The average LOH frequency on chromosome22q was 28.38 %. The region between markersD22S280 and D22S274 (22q12.2-q13.33) exhibitedrelatively high LOH frequency. The two highest LOH lociwith frequencies of 35.09 % and 34.04 % wasidentified on D22S280 (22q12.2-12.3) and D22S274(22q13.32-13.33). 8 cases showed LOH at allinformative loci, suggesting that one chromosome 22qhad been completely lost. On D22S274 locus, LOHfrequency of rectal cancer was 50 % (9/18), which washigher than that of proximal colon cancer (12 %, 2/17) (P=0.018). The frequency of distal colon cancer was42 % (5/12), also higher than that of proximal coloncancer. But there was no statistical significance. Puttingboth the tumors in distal colon and rectum togetherinto consideration, the frequency, 47 % (14/30), washigher than that of proximal colon cancer (P=0.015),suggesting the mechanism of carcinogenisis wasdifferent in both ***: This study provided evidence for theinvolvement of putative tumor suppressor genes relatedto the sporadic colorectal carcinoma on chromosome22q. The tumor-suppressor-gene(s) might locate on the22q12.2-12.3 and/or 22q13.32-13.33.

关键词：散发性直肠癌 22染色体等位基因杂合性丢失