Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect o...Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect of temperature on land subsidence has received practically no attention in the past.This paper presents a thermo-hydro-mechanical(THM)coupled numerical study on an ATES system in Shanghai,China.Four water wells were installed for seasonal heating and cooling of an agriculture greenhouse.The target aquifer at a depth of 74e104.5 m consisted of alternating layers of sand and silty sand and was covered with clay.Groundwater level,temperature,and land subsidence data from 2015 to 2017 were collected using field monitoring instruments.Constrained by data,we constructed a field scale three-dimensional(3D)model using TOUGH(Transport of Unsaturated Groundwater and Heat)and FLAC3D(Fast Lagrangian Analysis of Continua)equipped with a thermo-elastoplastic constitutive model.The effectiveness of the numerical model was validated by field data.The model was used to reproduce groundwater flow,heat transfer,and mechanical responses in porous media over three years and capture the thermo-and pressure-induced land subsidence.The results show that the maximum thermoinduced land subsidence accounts for about 60%of the total subsidence.The thermo-induced subsidence is slightly greater in winter than that in summer,and more pronounced near the cold well area than the hot well area.This study provides some valuable guidelines for controlling land subsidence caused by ATES systems installed in soft soils.展开更多
自动化测试系统(Automatic Test System, ATS)是无线电检测、计量实验室必不可少的测试工具,ATS测量不确定度评估的重要性也被广泛认可,但是ATS测量不确定度的评定算法得到国际组织公认的却不多。本文基于GUM(Guide to the Uncertainty ...自动化测试系统(Automatic Test System, ATS)是无线电检测、计量实验室必不可少的测试工具,ATS测量不确定度评估的重要性也被广泛认可,但是ATS测量不确定度的评定算法得到国际组织公认的却不多。本文基于GUM(Guide to the Uncertainty in Measurement)法提出了一种误差校准链路的ATS测量不确定度分析方法。首先,介绍了蓝牙产品认证中射频一致性ATS的溯源、校准,通过对系统测量链上测量不确定度原理的分析,可以得知ATS的误差校准引入了测量不确定度。其次,对蓝牙认证射频一致性ATS的测量链进行理论推导并计算测量数据。最后,结果表明,本文提出的误差校准链路的ATS测量不确定度分析方法具有可行性。展开更多
基金sponsored by the National Key Research and Development Program of China(Grant No.2020YFC1808102).
文摘Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect of temperature on land subsidence has received practically no attention in the past.This paper presents a thermo-hydro-mechanical(THM)coupled numerical study on an ATES system in Shanghai,China.Four water wells were installed for seasonal heating and cooling of an agriculture greenhouse.The target aquifer at a depth of 74e104.5 m consisted of alternating layers of sand and silty sand and was covered with clay.Groundwater level,temperature,and land subsidence data from 2015 to 2017 were collected using field monitoring instruments.Constrained by data,we constructed a field scale three-dimensional(3D)model using TOUGH(Transport of Unsaturated Groundwater and Heat)and FLAC3D(Fast Lagrangian Analysis of Continua)equipped with a thermo-elastoplastic constitutive model.The effectiveness of the numerical model was validated by field data.The model was used to reproduce groundwater flow,heat transfer,and mechanical responses in porous media over three years and capture the thermo-and pressure-induced land subsidence.The results show that the maximum thermoinduced land subsidence accounts for about 60%of the total subsidence.The thermo-induced subsidence is slightly greater in winter than that in summer,and more pronounced near the cold well area than the hot well area.This study provides some valuable guidelines for controlling land subsidence caused by ATES systems installed in soft soils.
文摘自动化测试系统(Automatic Test System, ATS)是无线电检测、计量实验室必不可少的测试工具,ATS测量不确定度评估的重要性也被广泛认可,但是ATS测量不确定度的评定算法得到国际组织公认的却不多。本文基于GUM(Guide to the Uncertainty in Measurement)法提出了一种误差校准链路的ATS测量不确定度分析方法。首先,介绍了蓝牙产品认证中射频一致性ATS的溯源、校准,通过对系统测量链上测量不确定度原理的分析,可以得知ATS的误差校准引入了测量不确定度。其次,对蓝牙认证射频一致性ATS的测量链进行理论推导并计算测量数据。最后,结果表明,本文提出的误差校准链路的ATS测量不确定度分析方法具有可行性。