Droplet turbulence effect on gas-water separator with corrugated plates is explored using the Eulerian-Lagrangian two-way coupled multiphase approach of FLUENT. It is concluded that the inertial force is dominant in s...Droplet turbulence effect on gas-water separator with corrugated plates is explored using the Eulerian-Lagrangian two-way coupled multiphase approach of FLUENT. It is concluded that the inertial force is dominant in separating large droplets, while droplet turbulence dispersion plays a decisive role in separating fine droplets. Good agreement exists between calculations and air-water experiments. The numerical method developed provides a rea-sonable description of the droplet trajectories and separating efficiency, and it can be applied to predicting the performance of gas-water separator with corrugated plates.展开更多
Based on the microfluidic technology,a microscopic visualization model was used to simulate the gas injection process in the initial construction stage and the bottom water invasion/gas injection process in the cyclic...Based on the microfluidic technology,a microscopic visualization model was used to simulate the gas injection process in the initial construction stage and the bottom water invasion/gas injection process in the cyclical injection-production stage of the underground gas storage(UGS)rebuilt from water-invaded gas reservoirs.Through analysis of the gas-liquid contact stabilization mechanism,flow and occurrence,the optimal control method for lifecycle efficient operation of UGS was explored.The results show that in the initial construction stage of UGS,the action of gravity should be fully utilized by regulating the gas injection rate,so as to ensure the macroscopically stable migration of the gas-liquid contact,and greatly improve the gas sweeping capacity,providing a large pore space for gas storage in the subsequent cyclical injection-production stage.In the cyclical injection-production stage of UGS,a constant gas storage and production rate leads to a low pore space utilization.Gradually increasing the gas storage and production rate,that is,transitioning from small volume to large volume,can continuously break the hydraulic equilibrium of the remaining fluid in the porous media,which then expands the pore space and flow channels.This is conducive to the expansion of UGS capacity and efficiency for purpose of peak shaving and supply guarantee.展开更多
针对煤炭地下气化(UCG)技术制备的合成气具有温度高(>200℃)、压力大(3.35 MPa)、饱和含水量大及组分复杂(含CH_(4)、H_(2)、CO_(2)和CO等)的特点,设计并采用膜分离+溶剂吸收耦合的处理方法以实现地下煤合成气中CO_(2)的脱除和H_(2)...针对煤炭地下气化(UCG)技术制备的合成气具有温度高(>200℃)、压力大(3.35 MPa)、饱和含水量大及组分复杂(含CH_(4)、H_(2)、CO_(2)和CO等)的特点,设计并采用膜分离+溶剂吸收耦合的处理方法以实现地下煤合成气中CO_(2)的脱除和H_(2)的提纯。地下煤合成气经过二级膜分离单元的处理,实现了CO_(2)/H_(2)与CH_(4)的分离并得到了脱碳净化气,其中CO_(2)含量(物质的量分数)≤3%,该膜分离工艺所需能耗为0.297 k W·h/m^(3)。使用醇胺吸收法处理CO_(2)/H_(2)混合气,并通过配方溶液筛选、工艺流程优化和校验分析等方法开展了研究,最终得到了H_(2)纯度(物质的量分数)≥99%的产品,该醇胺吸收法的能耗为0.341 k W·h/m^(3)。使用膜分离+溶剂吸收耦合处理复杂工况的地下煤合成气,可得到脱碳净化气、纯CO_(2)和工业级H_(2),提高了项目的经济价值,具有较大的应用潜力。展开更多
A numerical approach is presented to study the explosion-induced pressure load on an underground rock chamber wall and its resultant damage to the rock chamber.Numerical simulations are carried out by using a modified...A numerical approach is presented to study the explosion-induced pressure load on an underground rock chamber wall and its resultant damage to the rock chamber.Numerical simulations are carried out by using a modified version of the commercial software AUTODYN.Three different criteria,i.e.a peak particle velocity (PPV) criterion,an effective strain (ES) criterion,and a damage criterion,are employed to examine the explosion-induced damaged zones of the underground rock chamber.The results show that the charge chamber geometry,coupling condition and charge configuration affect significantly the dynamic pressure exerted on the rock chamber wall.Thus the chamber is damaged.An inaccurate approximation of pressure boundary ignoring the influences of these factors would result in an erroneous prediction of damaged area and damage intensity of the charge chamber.The PPV criterion yields the largest damaged zone while the ES criterion gives the smallest one.The presented numerical simulation method is superior in consideration of the chamber geometry,loading density,coupling condition and rock quality.The predicted damage intensity of rock mass can be categorized quantitatively by an isotropic damage scalar.Safe separation distance of adjacent chambers for a specific charge weight is also estimated.展开更多
基金Supported by National Key Laboratory of Bubble Physics and Natural Circulation (2005)
文摘Droplet turbulence effect on gas-water separator with corrugated plates is explored using the Eulerian-Lagrangian two-way coupled multiphase approach of FLUENT. It is concluded that the inertial force is dominant in separating large droplets, while droplet turbulence dispersion plays a decisive role in separating fine droplets. Good agreement exists between calculations and air-water experiments. The numerical method developed provides a rea-sonable description of the droplet trajectories and separating efficiency, and it can be applied to predicting the performance of gas-water separator with corrugated plates.
文摘Based on the microfluidic technology,a microscopic visualization model was used to simulate the gas injection process in the initial construction stage and the bottom water invasion/gas injection process in the cyclical injection-production stage of the underground gas storage(UGS)rebuilt from water-invaded gas reservoirs.Through analysis of the gas-liquid contact stabilization mechanism,flow and occurrence,the optimal control method for lifecycle efficient operation of UGS was explored.The results show that in the initial construction stage of UGS,the action of gravity should be fully utilized by regulating the gas injection rate,so as to ensure the macroscopically stable migration of the gas-liquid contact,and greatly improve the gas sweeping capacity,providing a large pore space for gas storage in the subsequent cyclical injection-production stage.In the cyclical injection-production stage of UGS,a constant gas storage and production rate leads to a low pore space utilization.Gradually increasing the gas storage and production rate,that is,transitioning from small volume to large volume,can continuously break the hydraulic equilibrium of the remaining fluid in the porous media,which then expands the pore space and flow channels.This is conducive to the expansion of UGS capacity and efficiency for purpose of peak shaving and supply guarantee.
文摘针对煤炭地下气化(UCG)技术制备的合成气具有温度高(>200℃)、压力大(3.35 MPa)、饱和含水量大及组分复杂(含CH_(4)、H_(2)、CO_(2)和CO等)的特点,设计并采用膜分离+溶剂吸收耦合的处理方法以实现地下煤合成气中CO_(2)的脱除和H_(2)的提纯。地下煤合成气经过二级膜分离单元的处理,实现了CO_(2)/H_(2)与CH_(4)的分离并得到了脱碳净化气,其中CO_(2)含量(物质的量分数)≤3%,该膜分离工艺所需能耗为0.297 k W·h/m^(3)。使用醇胺吸收法处理CO_(2)/H_(2)混合气,并通过配方溶液筛选、工艺流程优化和校验分析等方法开展了研究,最终得到了H_(2)纯度(物质的量分数)≥99%的产品,该醇胺吸收法的能耗为0.341 k W·h/m^(3)。使用膜分离+溶剂吸收耦合处理复杂工况的地下煤合成气,可得到脱碳净化气、纯CO_(2)和工业级H_(2),提高了项目的经济价值,具有较大的应用潜力。
文摘A numerical approach is presented to study the explosion-induced pressure load on an underground rock chamber wall and its resultant damage to the rock chamber.Numerical simulations are carried out by using a modified version of the commercial software AUTODYN.Three different criteria,i.e.a peak particle velocity (PPV) criterion,an effective strain (ES) criterion,and a damage criterion,are employed to examine the explosion-induced damaged zones of the underground rock chamber.The results show that the charge chamber geometry,coupling condition and charge configuration affect significantly the dynamic pressure exerted on the rock chamber wall.Thus the chamber is damaged.An inaccurate approximation of pressure boundary ignoring the influences of these factors would result in an erroneous prediction of damaged area and damage intensity of the charge chamber.The PPV criterion yields the largest damaged zone while the ES criterion gives the smallest one.The presented numerical simulation method is superior in consideration of the chamber geometry,loading density,coupling condition and rock quality.The predicted damage intensity of rock mass can be categorized quantitatively by an isotropic damage scalar.Safe separation distance of adjacent chambers for a specific charge weight is also estimated.
