A method for calculating the evolution of the local damage variable at the adiabatic shear band(ASB)center was proposed.In the present method,the JOHNSON-COOK model and the nonlocal theory were adopted,and the damage ...A method for calculating the evolution of the local damage variable at the adiabatic shear band(ASB)center was proposed.In the present method,the JOHNSON-COOK model and the nonlocal theory were adopted,and the damage variable formula applicable for the bilinear(linearly elastic and strain-softening)constitutive relation was further generalized to consider the plastic deformation occurring in the strain-hardening stage.Aiming at Ti-6Al-4V,the effect of strain rate on the evolution of the local damage variable at the ASB center was investigated.In addition,a parametric study was carried out,including the effects of strain-hardening exponent,strain rate sensitive coefficient,thermal-softening exponent,static shear strength,strain-hardening modulus,shear elastic modulus,work to heat conversion factor,melting temperature and initial temperature.The damage extent at the ASB center in the radial collapse experiment was assessed.It is found that at higher strain rates the damage in the ASB becomes more serious at the same average plastic shear strain of the ASB.展开更多
In order to understand the mechanism and regularity of the groundwater con- tamination from mine water of abandoned mines,experiments were conducted on an abandoned coal mine in Fuxin,a representative city with lots o...In order to understand the mechanism and regularity of the groundwater con- tamination from mine water of abandoned mines,experiments were conducted on an abandoned coal mine in Fuxin,a representative city with lots of mine water in northeast China.The groundwater pollution from different contaminants of coal-mining voids (total hardness,SO_4^(2-),Cl^-and total Fe) and pollution factors transportation situation in the coal rock were simulated by soil column experiment under the conditions of mine water leach- ing and main water leaching (similar to rainwater leaching),and the water-rock interaction mechanism was discussed during mine water infiltration through saturated coal rock by application of principle of mass conservation,based on physical properties of coal rock,as well as monitored chemical composition.The results show that,compared with the clear water leaching process,trends of change in pollutant concentrations presented different characteristics in the mine water leaching process.Groundwater is contaminated by the water rock interactions such as migration & accumulation,adsorption & transformation, dissolution & desorption and ion exchange during the mine water permeation.The expe- riments also suggest that at first dissolution rate of some kinds of dissoluble salts is high, but it decreases with leaching time,even to zero during both the mine water leaching and main water leaching.展开更多
When the gas flow in the compact porous medium at low speed,it has slippage effect which is caused by the gas molecular collision whit the solidskeleton.Using the gas transfusion slippage effect at researching the coa...When the gas flow in the compact porous medium at low speed,it has slippage effect which is caused by the gas molecular collision whit the solidskeleton.Using the gas transfusion slippage effect at researching the coal bed transfusion rule,established the transfusion mathematical model of the coal bed which had considered the slippage effect. Observing the influence of the different toencircle presses,the different hole press and the different actual stress to the coal bed by using the three-axles permeameter.Thus sum- marized the transfusion rule of the coal bed.The experiment indicates that the bigger of the surrounding pressure,the more obvious of the slippage effect.At the same condition of axial pressure and the surrounding pressure,with the increase of the hole pressure,the coal permeability became bigger and then smaller.The coal body effective tress and the permeability curve nearly also has the same change tendency.Thus we can draws the conclusion that the transfusion of the gas in the coal bed generally has the slippage effect.展开更多
Deformable micro-continua of highly localized nature are found to exactly exhibit all quantum effects commonly known for quantum entities at microscopic scale.At every instant,the spatial configuration of each such mi...Deformable micro-continua of highly localized nature are found to exactly exhibit all quantum effects commonly known for quantum entities at microscopic scale.At every instant,the spatial configuration of each such micro-continuum is prescribed by four spatial distributions of the mass,the velocity,the internal stress,and the intrinsic angular momentum.The deformability features of such micro-continua in response to all configuration changes are identified with a constitutive equation that specifies how the internal stress responds to the mass density field.It is shown that these microcontinua are endowed with the following unique response features:(i)the coupled system of the nonlinear field equations governing their dynamic responses to any given force and torque fields is exactly reducible to a linear dynamic equation governing a complex field variable;(ii)this fundamental dynamic equation and this complex field variable are just the Schrodinger equation and the complex wave function in quantum theory;and,accordingly,(iii)the latter two and all quantum effects known for quantum entities are in a natural and unified manner incorporated as the inherent response features of the micro-continua discovered,thus following objective and deterministic response patterns for quantum entities,in which the physical origins and meanings of the wave function and the Schrodinger equation become self-evident and,in particular,any probabilistic indeterminacy becomes irrelevant.展开更多
基金Supported by the Key National Natural Science Foundation of China （50434020） the Natural Science Foundation of Hebei Province, China （E2010000872, Z2009315）
基金Project(20081102)supported by the Doctor Startup Foundation of Liaoning Province,China
文摘A method for calculating the evolution of the local damage variable at the adiabatic shear band(ASB)center was proposed.In the present method,the JOHNSON-COOK model and the nonlocal theory were adopted,and the damage variable formula applicable for the bilinear(linearly elastic and strain-softening)constitutive relation was further generalized to consider the plastic deformation occurring in the strain-hardening stage.Aiming at Ti-6Al-4V,the effect of strain rate on the evolution of the local damage variable at the ASB center was investigated.In addition,a parametric study was carried out,including the effects of strain-hardening exponent,strain rate sensitive coefficient,thermal-softening exponent,static shear strength,strain-hardening modulus,shear elastic modulus,work to heat conversion factor,melting temperature and initial temperature.The damage extent at the ASB center in the radial collapse experiment was assessed.It is found that at higher strain rates the damage in the ASB becomes more serious at the same average plastic shear strain of the ASB.
基金the National Natural Science Foundation of China(50434020,50374042)Science & Technology Found of Liaoning Province(20022155)Specialized Research Fund for the Doctoral Program of Higher Education(20040147003)
文摘In order to understand the mechanism and regularity of the groundwater con- tamination from mine water of abandoned mines,experiments were conducted on an abandoned coal mine in Fuxin,a representative city with lots of mine water in northeast China.The groundwater pollution from different contaminants of coal-mining voids (total hardness,SO_4^(2-),Cl^-and total Fe) and pollution factors transportation situation in the coal rock were simulated by soil column experiment under the conditions of mine water leach- ing and main water leaching (similar to rainwater leaching),and the water-rock interaction mechanism was discussed during mine water infiltration through saturated coal rock by application of principle of mass conservation,based on physical properties of coal rock,as well as monitored chemical composition.The results show that,compared with the clear water leaching process,trends of change in pollutant concentrations presented different characteristics in the mine water leaching process.Groundwater is contaminated by the water rock interactions such as migration & accumulation,adsorption & transformation, dissolution & desorption and ion exchange during the mine water permeation.The expe- riments also suggest that at first dissolution rate of some kinds of dissoluble salts is high, but it decreases with leaching time,even to zero during both the mine water leaching and main water leaching.
基金the National Natural Sciences Fund Subsidization Project of China(50774041)National Important Item of the Natural Sciences Fund Subsidization Project of China(50490275)
文摘When the gas flow in the compact porous medium at low speed,it has slippage effect which is caused by the gas molecular collision whit the solidskeleton.Using the gas transfusion slippage effect at researching the coal bed transfusion rule,established the transfusion mathematical model of the coal bed which had considered the slippage effect. Observing the influence of the different toencircle presses,the different hole press and the different actual stress to the coal bed by using the three-axles permeameter.Thus sum- marized the transfusion rule of the coal bed.The experiment indicates that the bigger of the surrounding pressure,the more obvious of the slippage effect.At the same condition of axial pressure and the surrounding pressure,with the increase of the hole pressure,the coal permeability became bigger and then smaller.The coal body effective tress and the permeability curve nearly also has the same change tendency.Thus we can draws the conclusion that the transfusion of the gas in the coal bed generally has the slippage effect.
基金Project supported by the National Natural Science Foundation of China(No.11372172)
文摘Deformable micro-continua of highly localized nature are found to exactly exhibit all quantum effects commonly known for quantum entities at microscopic scale.At every instant,the spatial configuration of each such micro-continuum is prescribed by four spatial distributions of the mass,the velocity,the internal stress,and the intrinsic angular momentum.The deformability features of such micro-continua in response to all configuration changes are identified with a constitutive equation that specifies how the internal stress responds to the mass density field.It is shown that these microcontinua are endowed with the following unique response features:(i)the coupled system of the nonlinear field equations governing their dynamic responses to any given force and torque fields is exactly reducible to a linear dynamic equation governing a complex field variable;(ii)this fundamental dynamic equation and this complex field variable are just the Schrodinger equation and the complex wave function in quantum theory;and,accordingly,(iii)the latter two and all quantum effects known for quantum entities are in a natural and unified manner incorporated as the inherent response features of the micro-continua discovered,thus following objective and deterministic response patterns for quantum entities,in which the physical origins and meanings of the wave function and the Schrodinger equation become self-evident and,in particular,any probabilistic indeterminacy becomes irrelevant.
基金Supported by the National Natural Science Foundation of China（Nos.51274119, 51774175） and the Open Projects of Research Center of Coal Resources Safe Mining and Clean Utilization, Liaening Province, China（No. LNTU16KF15）.
