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Experiments and sensitivity analyses for heat transfer in a meter-scale regularly fractured granite model with water flow

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第12期13卷 958-968页

作者： Wei LU1,2,Yan-yong XIANG1 (1School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China) (2State Key Laboratory of Simulation and Regulation of water Cycle in River Basin,China Institute of water Resources and Hydropower Research,Beijing 100038,China) School of Civil Engineering Beijing Jiaotong University State Key Laboratory of Simulation and Regulation of water Cycle in River Basin China Institute of Water Resources and Hydropower Research

Experiments of saturated water flow and heat transfer were conducted for a meter-scale model of regularly fractured granite. The fractured rock model （height 1502.5 ram, width 904 mm, and thickness 300 mm）, embedded with two vertical and two horizontal fractures of pre-set apertures, was constructed using 18 pieces of intact granite. The granite was taken from a site currently being investigated for a high-level nuclear waste repository in China. The experiments involved different heat source temperatures and vertical water fluxes in the embedded fractures either open or filled with sand. A finite difference scheme and computer code for calculation of water flow and heat transfer in regularly fractured rocks was developed, verified against both the experimental data and calculations from the TOUGH2 code, and employed for parametric sensitivity analyses. The experiments revealed that, among other things, the temperature distribution was influenced by water flow in the fractures, especially the water flow in the vertical fracture adjacent to the heat source, and that the heat conduction between the neighboring rock blocks in the model with sand-filled fractures was enhanced by the sand, with larger range of influence of the heat source and longer time for approaching asymptotic steady-state than those of the model with open fractures. The temperatures from the experiments were in general slightly smaller than those from the numerical calculations, probably due to the fact that a certain amount of outward heat transfer at the model perimeter was unavoidable in the experiments. The parametric sensitivity analyses indicated that the tem- perature distribution was highly sensitive to water flow in the fractures, and the water temperature in the vertical fracture adjacent to the heat source was rather insensitive to water flow in other fractures.

关键词： Fractured granite water flow Heat transfer Physical modeling Numerical calculation Sensitivity analysis

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Phase transition model of water flow irradiated by high-energy laser in a chamber

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Chinese Physics B 2014年第7期23卷 459-464页

作者：魏继锋孙利群张凯胡晓阳 State Key Laboratory of Precision Measurement Technology and Instrument Tsinghua University Institute of Applied Electronics China Academy of Engineering Physics Graduate School of China Academy of Engineering Physics Key Laboratory of Laser Science and Technology China Academy of Engineering Physics

In the absorption chamber of a high-energy laser energy meter, water is directly used as an absorbing medium and the interaction of the high-power laser and the water flow can produce a variety of physical phenomena such as phase transitions. The unit difference method is adopted to deduce the phase transition model for water flow irradiated by a high-energy laser. In addition, the model is simulated and verified through experiments. Among them, the experimental verification uses the photographic method, shooting the distribution and the form of the air mass of water flow in different operating conditions, which are compared with the simulation results. The research shows that it is achievable to reduce the intensity of the phase transition by increasing the water flow, reducing the power intensity of the beam, shortening the distance the beam covers, reducing the initial water temperature or adopting a shorter wavelength laser. The study＇s results will provide the reference for the design of a water-direct-absorption-type high-energy laser energy meter as well as an analysis of the interaction processes of other similar high-power lasers and water flow.

关键词： phase transition high-energy laser water flow photographic method

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Laboratory investigation into the oil diffusion from submarine pipeline under water flow

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Acta Oceanologica Sinica 2018年第11期37卷 96-103页

作者： JIANG Meirong YU Jianxing LI Zhigang ZHONG Wenjun WU Zhaohui YU Yang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University CNOOC Research Institute Co. Ltd. China National Offshore Oil Corporation (CNOOC) Offshore Oil Engineering Co. Ltd. China National Offshore Oil Corporation (CNOOC) State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

A physical model test has been conducted to study the oil diffusion from the submarine pipeline under water *** crude oil in the flume is spilled from a leakage point of the pipeline and diffused from the seabed to the surface. By the non-contact optical measuring technology, an image acquisition and data analysis system is designed to explore the spilled mechanism and characteristic. The oil trajectory, velocity and the rising time to the surface are obtained through this system. The influence of the water flow and the spilled discharge on the behavior of the spilled oil are analyzed from both qualitative and quantitative perspectives. The sensitivity study of the characteristic physical quantities to various factors are presented afterward. The spilled oil under water is mainly distributed in the form of the scattered particles with different sizes. The rising process of the oil can be divided into three stages: full, dispersion and aggregation period. The spilled discharge is the primary factor affecting the rising time of the oil particles. In the rising process of the oil particles, the vertical velocity of the oil is mainly affected by the spilled discharge, and the transverse velocity is more dependent on the water velocity. The deviation of the transverse oil velocity is much larger than that of the rising time and the vertical oil velocity. The study can provide a theoretical reference for the prediction system of oil spill emergency.

关键词： oil diffusion submarine pipeline model test water flow spilled discharge

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water flow simulation and analysis in HMA microstructure

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Journal of Traffic and Transportation Engineering(English Edition) 2014年第5期1卷 362-370页

作者： Can Chen R.Christopher Williams Graniterock Construction Company Department of Civil Constructionand Environmental EngineeringIowa State University

This paper introduces a new method for reconstructing virtual two-dimensional （2-D） micro- structure of hot mix asphalt （HMA）. Based on the method, the gradation of coarse aggregates and the film thickness of the asphalt binder can be defined by the user. The HMA microstructure then serves as the input to the computational fluid dynamic （CFD） software （ANSYS-FLUENT） to investigate the water flow pattern through it. It is found that the realistic flow fields can be simulated in the 2-D micro- structure and the flow patterns in some typical air void structures can be identified. These flow patterns can be used to explain the mechanism that could result in moisture damage in HMA pavement. The one-dimensional numerical permeability values are also derived from the flow fields of the 2-D HMA microstructure and compared with the measured values obtained by the Karol-Warner permeameter. Be- cause the interconnected air voids channels in actual HMA samples cannot be fully represented in a 2-D model, some poor agreements need to be improved.

关键词： hot mix asphalt microstructure simulation water flow

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Effects of water flow on the uptake of phosphorus by sediments： An experimental investigation

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Journal of Hydrodynamics 2016年第2期28卷 329-332页

作者：肖洋成浩科余维维李志伟 State Key Laboratory of Hydrology-water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China College of water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

This paper investigates the effect of the water flow on the phosphorus uptake by sediments. Five experiments with different overlying flow velocities are carried out in an annular flume. The results show that the water flow significantly affects the phosphorus uptake by sediments. The sediment motion could be stationary, scroll, scroll or saltation, saltation and suspension under different flow conditions. The minimum amount of the phosphorus uptake is observed where the sediment motion is stationary. The uptake capacity of phosphorus increases with the increase of the flow velocity. However, there is no apparent difference in the uptake capacity of phosphorus between the saltated and suspended sediments. The uptake rate of phosphorus by sediments in the laboratory flume experiments is much lower than the adsorption rate in the batch experiments. There is a linear relationship between the amount of phosphorus uptake by sediments and the square root of time.

关键词： water flow phosphorus uptake flume

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Natural Convective Heat and Mass Transfer on a Vertical Heated Plate for water flow Containing Metal Corrosion Particles

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Journal of Thermal Science 1992年第1期1卷 11-18页

作者： Pei－xueJiang Ze－peiRen 等 DepartmentofThermalEngineering TsinghuaUniversityBeijing100084China DepartmentofThermalEngineering

Corrosion products of structural materials when contained in water usually are in two states:soluble state and colloidal particles with diameter about 10^(-3)—10^(-1)μ*** of such corrosion products on tube surfaces under high pressure will jeopardize the operating economy of power plant equipment and even result in accidents. A numerical study is reported in this paper of the natural convective heat and mass transfer on a vertical heated plate subject to the first or mixed kind of boundary conditions for high-pressure water(P=17MPa)containing metal corrosion products with consideration of variable thermophysical properties.

关键词： metal corrosion products water flow natural convection heat and mass transfer variable thermophysical properties.

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Study of water flow in a Single Clay Crack

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Acta Geologica Sinica(English Edition) 1993年第4期67卷 443-451页

作者： Ge Zhonghua, Nanjing University, Nanjing, Jiangsu Fan Bingheng, Feng Qiyan and Wang Yonghong China University of Mining and Technology, Xuzhou, Jiangsu Wang Xichuan Nanjing University Nanjing Jiangsu China

A model has been constructed to study water flow in a single clay crack, and a new concept of the critical rise rate of water level in the crack has been put forward. When the water level rises faster than this critical rate, the flow in a crack will increase, and vice versa. The flow in a crack is not in proportion to the water level. The maximium water flow in clay is 30-40 times smaller than that in a rock fissure under the same condition. In the process of water discharge, the flow in a crack will lessen gradually, and the crack will grow narrower by 3.0-4.0cm, with its depth reducing by over 50%.

关键词： clay crack water flow critical rise rate of water level expansion and collapse

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The effects of water flow and temperature on thermal regime around a culvert built on permafrost

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Research in Cold and Arid Regions 2014年第5期6卷 415-422页

作者： Loriane Périer Guy Doré C.R.Burn Loriane Perier Guy Dore C. R. Bum Laval University Center for Northern Studies (CEN) 1035 Avenue De la m~decine QuObec Canada G1A OA6 Carleton University Dept. of Geography and Environmental Studies Ottawa Ontario Canada K1S 5B6

Temperature and water flow through a culvert beneath the Alaska Highway near Beaver Creek,Yukon,were measured at hourly intervals between June and October *** data were used to simulate the effect of the culvert on the thermal regime of the road embankment and subjacent permafrost.A 2-D thermal model of the embankment and permafrost was developed with TEMP/W and calibrated using field *** relations were obtained between water temperatures at the entrance to the culvert,flow into the culvert,and water temperatures inside the *** temperatures at the entrance and inside the culvert had a linear relation,while water temperatures inside the culvert and water flow were associated by a logarithmic relation.A multiple linear regression was used to summarize these *** this relationship,changes in the flow rate and water temperatures at the entrance of the culvert were simulated to obtain predicted water temperatures in the *** temperatures in the culvert were used in the thermal model to determine their effects on the ground thermal regime near the *** of ±10% in water flow rate had no impact on the thermal regime underneath the *** of water temperature at the entrance of the culvert had a noticeable influence on the thermal regime.A final simulation was conducted without insulation beneath the *** thaw depth was 30 cm with insulation,and 120 cm without insulation,illustrating the importance of insulation to the ground thermal regime.

关键词： culvert thermal regime water flow water temperature modeling permafrost

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water flow and Sediment Flux Forecast in the ChókwèIrrigation Scheme, Mozambique

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Journal of water Resource and Protection 2020年第12期12卷 1089-1122页

作者： Lateiro Salvador De Sousa Raphael Muli Wambua James Messo Raude Benedict Mwavu Mutua Division of Agriculture Instituto Superior Politécnico de Gaza Campus Politécnico de Lionde Chókwè-Gaza Province Mozambique Department of Agricultural Engineering Egerton University Nakuru Kenya Soil Water & Environmental Engineering Department Jomo Kenyatta University of Agriculture & Technology Nairobi Kenya Division of Planning Partnerships Research and Innovation Kibabii University Bungoma Kenya

This study sought to forecast water flow and sediment flux in the scheme as potential contributions for improved management in the Chókwè Irrigation Scheme (CIS). Fieldwork data was collected during dry (DS) and wet (WS) seasons. flow measurement was performed at 9 stations using a calibrated flow meter OTT C31. water flow and sediment flux from 2004 to 2019 were used. Hydrodynamic forecast simulations were performed using Mann-Kendall test and ARIMA model for determination of temporal trends. Findings suggest higher values during DS for water discharge and sediment flux. Mann-Kendall test for sediment discharge trends was not significant at 95% significance level, except for the Offtake in WS. ARIMA test for the sediment discharges, at the Intake, for DS and WS, sediments were well described by the ARIMA model and gave a good result for the sediments. Good fit between the observed and the predicted ARIMA model was found. ARIMA model for sediment discharge at CIS based on AIC has a good fit for AR (p = 1), whereby, at the Intake the ARIMA p-value was 0.822 and 0.932, for WS and DS, respectively. Whilst in the Offtake, the ARIMA p-value was 0.877 and 0.893, respectively. These results can be used to improve the CIS management, both for water flow and sediment flux.

关键词： water flow Sediment Flux Mann-Kendall Test ARIMA Model Chókwè Irrigation Scheme

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Spatial matching and flow in supply and demand of water provision services: A case study in Xiangjiang River Basin

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Journal of Mountain Science 2022年第1期19卷 228-240页

作者： DENG Chu-xiong ZHU Da-mei LIU Yao-jun LI Zhong-wu College of Resources and Environmental Sciences Hunan Normal UniversityChangsha 410081China Hunan Key Laboratory of Geospatial Big Data Mining and Application Changsha 410081China College of Environmental Science and Engineering Hunan UniversityChangsha 410082China

Global climate change and increased human consumption have aggravated the uneven spatiotemporal distribution of watershed water resources, affecting the water provision supply and demand state. However, this problem has often been ignored. The present study used the Xiangjiang River basin(XRB) as the study area, and the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST) model, demand quantification model,supply–demand ratio, and water flow formula were applied to explore the spatial heterogeneity, flow, and equilibrium between water supply and demand. The results demonstrated significant spatial heterogeneity in the upstream, midstream, and downstream *** areas of water shortage were mainly located the downstream of the Changsha–Zhuzhou–Xiangtan urban agglomeration, and the Hengyang basin was the most scarcity area. Affected by terrain gradients and human needs, water flow varied from-16.33 × 10^(8) m^(3) to 13.69 × 10^(8) m^(3)from the upstream to the downstream area, which provided a possibility to reduce spatial heterogeneity. In the future, measures such as strengthening water resource system control,sponge city construction, and dynamic monitoring technology should be taken to balance the supply and demand of water in different river sections of the basin. This study can provide references for regulating water resources allocation in different reaches of the basin.

关键词： water provision services Supply and demand Spatiotemporal dislocation water flow water management and saving policy Xiangjiang River basin

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