Chin-fu Tsang - Academia.edu (original) (raw)
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Papers by Chin-fu Tsang
Flow and solute transport through porous medium with strongly varying hydraulic conductivity are ... more Flow and solute transport through porous medium with strongly varying hydraulic conductivity are studied by numerical simulations. The heterogeneity of the porous medium is defined by Ï and λâ², which are, respectively, the standard deviation of natural log of permeability values and its correlation range λ divided by transport distance L. The development of flow channeling as a function of
Geophysical Monograph Series, 2013
Abstract: The interaction between mechanical deformation and fluid flow in fractured rock gives r... more Abstract: The interaction between mechanical deformation and fluid flow in fractured rock gives rise to a host of coupled hydromechanical processes, which form the basis of a number of interesting research questions with practical implications. This paper will first discuss these processes in general, describing two numerical models that have been developed to analyse these processes. Then, four very different studies will be presented to illustrate the richness of this field. The first study has to do with borehole injection testing to determine fracture parameters and how hydro-mechanical effects will modify test results. The second study is on stress changes (caused by stress release) in rock near a tunnel during excavation, which cause significant changes in fluid press-ures in the region. The third study is on the relationship between mechanical effects and flow aniso-tropy and channelling in a rock block with a fracture network. The fourth study pertains to the hydromechanical...
Computers and Geotechnics
Hydrogeology Journal, 2013
Water Resources Research, 2015
![Research paper thumbnail of Reply [to “Comment on ‘Flow and tracer transport in a single fracture: A stochastic model and its relation to some field observations’ by L. Moreno et al.”]](https://attachments.academia-assets.com/75953321/thumbnails/1.jpg)
](Water Resources Research, 1991
Heat Storage in aquifers involves injecting warm water into a confined aquifer and recovering the... more Heat Storage in aquifers involves injecting warm water into a confined aquifer and recovering the heat later by pumping out the warm water. Heat loss in the aquifers is roughly proportional to the area of the warm storage region which may be increased to unacceptable levels by buoyancy effects. Thermohydraulic problems in heat storage aquifers, methods for predicting the buoyancy
Hydrogeology Journal
Drilling of a deep borehole does not normally allow for hydrologic testing during the drilling pe... more Drilling of a deep borehole does not normally allow for hydrologic testing during the drilling period. It is only done when drilling experiences a large loss (or high return) of drilling fluid due to penetration of a large-transmissivity zone. The paper proposes the possibility of conducting flowing fluid electric conductivity (FFEC) logging during the drilling period, with negligible impact on the drilling schedule, yet providing important information on depth locations of both high- and low-transmissivity zones and their hydraulic properties. The information can be used to guide downhole fluid sampling and post-drilling detailed testing of the borehole. The method has been applied to the drilling of a 2500-m borehole at Åre, central Sweden, firstly when the drilling reached 1600 m, and then when the drilling reached the target depth of 2500 m. Results unveil eight hydraulically active zones from 300 m down to borehole bottom, with depths determined to within the order of a meter. Further, the first set of data allows the estimation of hydraulic transmissivity values of the six hydraulically conductive zones found from 300 to 1600 m, which are very low and range over one order of magnitude.
Coupled Thermo-Hydro-Mechanical Processes of Fractured Media - Mathematical and Experimental Studies
ABSTRACT The international co-operative research project— DECOVALEX- is presented. The project wa... more ABSTRACT The international co-operative research project— DECOVALEX- is presented. The project was initiated as a collective research effort to further our understanding of the coupled thermo-hydro-mechanical processes in fractured media and engineered buffer materials, and validate mathematical models and computer codes against experiments for radioactive waste isolation. The presentation summarizes the organization, structure, approaches and management of the project briefly, followed by an outline of the Bench-Mark-Test (BMT) and Test Case (TC) problems studied in the project. The scientific achievements and lessons learned are briefly discussed at the end.
The LBL numerical model used is called CCC which stands for Conduction, Convection, and Compactio... more The LBL numerical model used is called CCC which stands for Conduction, Convection, and Compaction. The model computes heat and mass flow in three-dimensional water saturated porous systems. Concurrent with the mass and energy flow, the vertical deformation of the geothermal system is simulated using the one-dimensional consolidation theory of Terzaghi. Thus the following physical effects can be included simultaneously
International Journal of Greenhouse Gas Control, 2015
Flow and solute transport through porous medium with strongly varying hydraulic conductivity are ... more Flow and solute transport through porous medium with strongly varying hydraulic conductivity are studied by numerical simulations. The heterogeneity of the porous medium is defined by Ï and λâ², which are, respectively, the standard deviation of natural log of permeability values and its correlation range λ divided by transport distance L. The development of flow channeling as a function of
Geophysical Monograph Series, 2013
Abstract: The interaction between mechanical deformation and fluid flow in fractured rock gives r... more Abstract: The interaction between mechanical deformation and fluid flow in fractured rock gives rise to a host of coupled hydromechanical processes, which form the basis of a number of interesting research questions with practical implications. This paper will first discuss these processes in general, describing two numerical models that have been developed to analyse these processes. Then, four very different studies will be presented to illustrate the richness of this field. The first study has to do with borehole injection testing to determine fracture parameters and how hydro-mechanical effects will modify test results. The second study is on stress changes (caused by stress release) in rock near a tunnel during excavation, which cause significant changes in fluid press-ures in the region. The third study is on the relationship between mechanical effects and flow aniso-tropy and channelling in a rock block with a fracture network. The fourth study pertains to the hydromechanical...
Computers and Geotechnics
Hydrogeology Journal, 2013
Water Resources Research, 2015
Water Resources Research, 1991
Heat Storage in aquifers involves injecting warm water into a confined aquifer and recovering the... more Heat Storage in aquifers involves injecting warm water into a confined aquifer and recovering the heat later by pumping out the warm water. Heat loss in the aquifers is roughly proportional to the area of the warm storage region which may be increased to unacceptable levels by buoyancy effects. Thermohydraulic problems in heat storage aquifers, methods for predicting the buoyancy
Hydrogeology Journal
Drilling of a deep borehole does not normally allow for hydrologic testing during the drilling pe... more Drilling of a deep borehole does not normally allow for hydrologic testing during the drilling period. It is only done when drilling experiences a large loss (or high return) of drilling fluid due to penetration of a large-transmissivity zone. The paper proposes the possibility of conducting flowing fluid electric conductivity (FFEC) logging during the drilling period, with negligible impact on the drilling schedule, yet providing important information on depth locations of both high- and low-transmissivity zones and their hydraulic properties. The information can be used to guide downhole fluid sampling and post-drilling detailed testing of the borehole. The method has been applied to the drilling of a 2500-m borehole at Åre, central Sweden, firstly when the drilling reached 1600 m, and then when the drilling reached the target depth of 2500 m. Results unveil eight hydraulically active zones from 300 m down to borehole bottom, with depths determined to within the order of a meter. Further, the first set of data allows the estimation of hydraulic transmissivity values of the six hydraulically conductive zones found from 300 to 1600 m, which are very low and range over one order of magnitude.
Coupled Thermo-Hydro-Mechanical Processes of Fractured Media - Mathematical and Experimental Studies
ABSTRACT The international co-operative research project— DECOVALEX- is presented. The project wa... more ABSTRACT The international co-operative research project— DECOVALEX- is presented. The project was initiated as a collective research effort to further our understanding of the coupled thermo-hydro-mechanical processes in fractured media and engineered buffer materials, and validate mathematical models and computer codes against experiments for radioactive waste isolation. The presentation summarizes the organization, structure, approaches and management of the project briefly, followed by an outline of the Bench-Mark-Test (BMT) and Test Case (TC) problems studied in the project. The scientific achievements and lessons learned are briefly discussed at the end.
The LBL numerical model used is called CCC which stands for Conduction, Convection, and Compactio... more The LBL numerical model used is called CCC which stands for Conduction, Convection, and Compaction. The model computes heat and mass flow in three-dimensional water saturated porous systems. Concurrent with the mass and energy flow, the vertical deformation of the geothermal system is simulated using the one-dimensional consolidation theory of Terzaghi. Thus the following physical effects can be included simultaneously
International Journal of Greenhouse Gas Control, 2015