在系统分析淮南煤田大量地面钻孔井温测井数据和井下巷道围岩温度测试数据的基础上,结合58块岩石样品的热导率测试结果,全面阐述了该区现今地温梯度和大地热流的分布特征。研究表明,淮南煤田现今地温梯度的众值介于2.50-3.50℃/hm之间,...在系统分析淮南煤田大量地面钻孔井温测井数据和井下巷道围岩温度测试数据的基础上,结合58块岩石样品的热导率测试结果,全面阐述了该区现今地温梯度和大地热流的分布特征。研究表明,淮南煤田现今地温梯度的众值介于2.50-3.50℃/hm之间,平均地温梯度为2.9℃/hm;大地热流值变化范围为31.87-83.9 m W/m^2,平均热流值为63.69 m W/m^2,地温梯度和热流值区均高于淮北煤田;大地热流受地温梯度控制明显,其变化特征和地温梯度分布较为相似,整体表现为中东部高,西部其次,东南部最小的特征。分析揭示,区内现今地温场和热流分布主要受区域地质背景和区内构造格局的控制。展开更多
This paper has studied the thermodynamic performance of a thermal Brownian heat pump,which consists of Brownian particles moving at a periodic sawtooth potential with external forces and contacting with the alternatin...This paper has studied the thermodynamic performance of a thermal Brownian heat pump,which consists of Brownian particles moving at a periodic sawtooth potential with external forces and contacting with the alternating hot and cold reservoirs along the space coordinate.The heat flows driven by both potential and kinetic energies are taken into account.The analytical expressions for the heating load,coefficient of performance(COP) and power input of the Brownian heat pump are derived and the performance characteristics are obtained by numerical calculations.It is shown that due to the heat flow via the change of kinetic energy of the particles,the Brownian heat pump is always irreversible and the COP can never attain the Carnot COP.The study has also investigated the influences of the operating parameters,i.e.the external force,barrier height of the potential,asymmetry of the sawtooth potential and temperature ratio of the heat reservoirs,on the performance of the Brownian heat pump.The effective regions of external force and barrier height of the potential in which the Brownian motor can operates as a heat pump are determined.The results show that the performance of the Brownian heat pump greatly depends on the parameters;if the parameters are properly chosen,the Brownian heat pump may be controlled to operate in the optimal regimes.展开更多
文摘在系统分析淮南煤田大量地面钻孔井温测井数据和井下巷道围岩温度测试数据的基础上,结合58块岩石样品的热导率测试结果,全面阐述了该区现今地温梯度和大地热流的分布特征。研究表明,淮南煤田现今地温梯度的众值介于2.50-3.50℃/hm之间,平均地温梯度为2.9℃/hm;大地热流值变化范围为31.87-83.9 m W/m^2,平均热流值为63.69 m W/m^2,地温梯度和热流值区均高于淮北煤田;大地热流受地温梯度控制明显,其变化特征和地温梯度分布较为相似,整体表现为中东部高,西部其次,东南部最小的特征。分析揭示,区内现今地温场和热流分布主要受区域地质背景和区内构造格局的控制。
基金supported by the Program for New Century Excellent Talents in University of China (Grant No. NCET-04-1006)the Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 200136)
文摘This paper has studied the thermodynamic performance of a thermal Brownian heat pump,which consists of Brownian particles moving at a periodic sawtooth potential with external forces and contacting with the alternating hot and cold reservoirs along the space coordinate.The heat flows driven by both potential and kinetic energies are taken into account.The analytical expressions for the heating load,coefficient of performance(COP) and power input of the Brownian heat pump are derived and the performance characteristics are obtained by numerical calculations.It is shown that due to the heat flow via the change of kinetic energy of the particles,the Brownian heat pump is always irreversible and the COP can never attain the Carnot COP.The study has also investigated the influences of the operating parameters,i.e.the external force,barrier height of the potential,asymmetry of the sawtooth potential and temperature ratio of the heat reservoirs,on the performance of the Brownian heat pump.The effective regions of external force and barrier height of the potential in which the Brownian motor can operates as a heat pump are determined.The results show that the performance of the Brownian heat pump greatly depends on the parameters;if the parameters are properly chosen,the Brownian heat pump may be controlled to operate in the optimal regimes.
