Ventilation system is significant in underground metal mine of alpine region.Reasonable evaluation of ventilation effectiveness will lead to a practical improvement for the maintenance and management of ventilation sy...Ventilation system is significant in underground metal mine of alpine region.Reasonable evaluation of ventilation effectiveness will lead to a practical improvement for the maintenance and management of ventilation system.However,it is difficult to make an effective evaluation of ventilation system due to the lack of classification criteria with respect to underground metal mine in alpine region.This paper proposes a novel evaluation method called the cloud model-clustering analysis(CMCA).Cloud model(CM)is utilized to process collected data of ventilation system,and they are converted into cloud descriptors by CM.Cloud similarity(CS)based Euclidean distance(ED)is proposed to make clustering analysis of assessed samples.Then the classification of assessed samples will be identified by clustering analysis results.A case study is developed based on CMCA.Evaluation results show that ventilation effectiveness can be well classified.Moreover,CM is used alone to make comparison of evaluation results obtained by CMCA.Then the availability and validity of CMCA is verified.Meanwhile,difference of CS based ED and classical ED is analyzed.Two new clustering analysis methods are introduced to make comparison with CMCA.Then the ability of proposed CMCA to meet evaluation requirements of ventilation system is verified.展开更多
Hongtoushan copper mine was studied by analyzing the type of heat source, the calculation method about thermal releasing in stope,thermal transfer between rock and air,distribution of temperature in stope were formula...Hongtoushan copper mine was studied by analyzing the type of heat source, the calculation method about thermal releasing in stope,thermal transfer between rock and air,distribution of temperature in stope were formulated.With CFD (Computational Fluid Dynamics,DFD) simulation and Fluent software,geometrical model of a stope was built,boundary conditions was initialized,then the temperature distribution,velocity and pressure field,concentration of oxygen and CO2 of air were simulated.In order to validate the simulation result,the parameters of the stope were measured with meter,and com- paring with the data of simulation.The result shows that the data of measuring and simu- lating are compatible.According to the distribution of temperature and velocity,some ways such as flow angle and flow velocity are put forward,simulation and parameter optimiza- tion made also,a satisfied result is acquired.The conclusion can be used on ventilation designing and stope improving.展开更多
There is very low permeability of coal seams in Polish coal mines. For this reason, pre-mining methane drainage is conducted to a small extent, which rarely brings expected results. Methane emission from roof and floo...There is very low permeability of coal seams in Polish coal mines. For this reason, pre-mining methane drainage is conducted to a small extent, which rarely brings expected results. Methane emission from roof and floor sub-economic seams has the greatest share in total methane emission to workings. Effective CMM （coal mine methane） capture is used from goaf in advance or after mining. However, due to longwall mining and ventilation systems, it is not always possible to capture methane from strata. This paper presents a method of increasing the permeability of coal seams and a method of drilling boreholes towards goaf. Initial results of the effectiveness of methane capture after applying these methods are presented.展开更多
基金Project(2018YFC0808404)supported by National Key Research and Development Program of China。
文摘Ventilation system is significant in underground metal mine of alpine region.Reasonable evaluation of ventilation effectiveness will lead to a practical improvement for the maintenance and management of ventilation system.However,it is difficult to make an effective evaluation of ventilation system due to the lack of classification criteria with respect to underground metal mine in alpine region.This paper proposes a novel evaluation method called the cloud model-clustering analysis(CMCA).Cloud model(CM)is utilized to process collected data of ventilation system,and they are converted into cloud descriptors by CM.Cloud similarity(CS)based Euclidean distance(ED)is proposed to make clustering analysis of assessed samples.Then the classification of assessed samples will be identified by clustering analysis results.A case study is developed based on CMCA.Evaluation results show that ventilation effectiveness can be well classified.Moreover,CM is used alone to make comparison of evaluation results obtained by CMCA.Then the availability and validity of CMCA is verified.Meanwhile,difference of CS based ED and classical ED is analyzed.Two new clustering analysis methods are introduced to make comparison with CMCA.Then the ability of proposed CMCA to meet evaluation requirements of ventilation system is verified.
基金National Scientific and Technological 11th Five-Year Plan of China(2006BAK05B04-03)
文摘Hongtoushan copper mine was studied by analyzing the type of heat source, the calculation method about thermal releasing in stope,thermal transfer between rock and air,distribution of temperature in stope were formulated.With CFD (Computational Fluid Dynamics,DFD) simulation and Fluent software,geometrical model of a stope was built,boundary conditions was initialized,then the temperature distribution,velocity and pressure field,concentration of oxygen and CO2 of air were simulated.In order to validate the simulation result,the parameters of the stope were measured with meter,and com- paring with the data of simulation.The result shows that the data of measuring and simu- lating are compatible.According to the distribution of temperature and velocity,some ways such as flow angle and flow velocity are put forward,simulation and parameter optimiza- tion made also,a satisfied result is acquired.The conclusion can be used on ventilation designing and stope improving.
文摘There is very low permeability of coal seams in Polish coal mines. For this reason, pre-mining methane drainage is conducted to a small extent, which rarely brings expected results. Methane emission from roof and floor sub-economic seams has the greatest share in total methane emission to workings. Effective CMM （coal mine methane） capture is used from goaf in advance or after mining. However, due to longwall mining and ventilation systems, it is not always possible to capture methane from strata. This paper presents a method of increasing the permeability of coal seams and a method of drilling boreholes towards goaf. Initial results of the effectiveness of methane capture after applying these methods are presented.
