The underground or open-pit methods are used for the extraction of mineral resources,each of which is divided into different categories.Coal is one of the mineral resources,which is exploited either by the surface or ...The underground or open-pit methods are used for the extraction of mineral resources,each of which is divided into different categories.Coal is one of the mineral resources,which is exploited either by the surface or the underground methods.The long-wall mining is one of the methods for the underground coal mining.In this method,which is a mechanized one,some machines such as the shearer or plow are used for the mining.The coal mine in Parvadeh,Tabas is a mechanized mine that is extracted by the long-wall mining.The modeling with particle flow code software was used in this mine for the evaluation of plow performance using the coal specifications.In this regard,the sample was first calibrated by sampling from the Parvadeh coal mine and performing the uniaxial and Brazilian tests on the model.Then,the modeling was done by constructing the model and using the variables such as the clearance angle and the linear velocity of the plow.After making 28 models for the plow,the best model of the plow was selected based on the maximum force applied to the machine in the X direction.Finally,the results of this study showed that the best plow performance is for a model with the clearance angle of zero and the linear velocity of 9 mm/min,and the maximum force applied to this model is equal to 39,000 kN in the X direction.展开更多
The control system, which includes structure, the composition of software and hardware, the form of PID control system and its systematic closed-loop, was used in No.4236 full-mechanized coal face of Xinlongzhuang min...The control system, which includes structure, the composition of software and hardware, the form of PID control system and its systematic closed-loop, was used in No.4236 full-mechanized coal face of Xinlongzhuang mine. The typical fuzzy PID control system structure was investigated, and a simplified fuzzy PID control system was taken the place of the complex three-dimension fuzzy controller. Based on the parameter relation between fuzzy controller and normal PID controller, a common method of parameter adjustment of PID controller was summed up and the computer simulation was realized. This system can overcome the problems of large delay, nonlinear, poor running en- vironment and great load change in the full-mechanized coal face. The simulating investigation indicates that the de- signing method of fuzzy controller is simple and feasible.展开更多
According to the gas observational data,the gas spatiotemporal distributions were analyzed in full-mechanized top coal caving in thick,hard and high-gas seams.The factors influencing gas effusion were researched and t...According to the gas observational data,the gas spatiotemporal distributions were analyzed in full-mechanized top coal caving in thick,hard and high-gas seams.The factors influencing gas effusion were researched and the rules of gas effusion under the special conditions were educed,for example,the underground pressure,the output inten- sity,the working surface advancement,and the amount of ventilation in the working face on gas effusion,and so on.The research results can be the base of forecasting gas effu- sion and controlling gas in these special conditions,which can guarantee the safety of highly efficient full-mechanized top coal caving.展开更多
文摘The underground or open-pit methods are used for the extraction of mineral resources,each of which is divided into different categories.Coal is one of the mineral resources,which is exploited either by the surface or the underground methods.The long-wall mining is one of the methods for the underground coal mining.In this method,which is a mechanized one,some machines such as the shearer or plow are used for the mining.The coal mine in Parvadeh,Tabas is a mechanized mine that is extracted by the long-wall mining.The modeling with particle flow code software was used in this mine for the evaluation of plow performance using the coal specifications.In this regard,the sample was first calibrated by sampling from the Parvadeh coal mine and performing the uniaxial and Brazilian tests on the model.Then,the modeling was done by constructing the model and using the variables such as the clearance angle and the linear velocity of the plow.After making 28 models for the plow,the best model of the plow was selected based on the maximum force applied to the machine in the X direction.Finally,the results of this study showed that the best plow performance is for a model with the clearance angle of zero and the linear velocity of 9 mm/min,and the maximum force applied to this model is equal to 39,000 kN in the X direction.
文摘The control system, which includes structure, the composition of software and hardware, the form of PID control system and its systematic closed-loop, was used in No.4236 full-mechanized coal face of Xinlongzhuang mine. The typical fuzzy PID control system structure was investigated, and a simplified fuzzy PID control system was taken the place of the complex three-dimension fuzzy controller. Based on the parameter relation between fuzzy controller and normal PID controller, a common method of parameter adjustment of PID controller was summed up and the computer simulation was realized. This system can overcome the problems of large delay, nonlinear, poor running en- vironment and great load change in the full-mechanized coal face. The simulating investigation indicates that the de- signing method of fuzzy controller is simple and feasible.
基金the National Nature Science Fund(50574072)the Shaanxi Nature Science Fund(2007E230)
文摘According to the gas observational data,the gas spatiotemporal distributions were analyzed in full-mechanized top coal caving in thick,hard and high-gas seams.The factors influencing gas effusion were researched and the rules of gas effusion under the special conditions were educed,for example,the underground pressure,the output inten- sity,the working surface advancement,and the amount of ventilation in the working face on gas effusion,and so on.The research results can be the base of forecasting gas effu- sion and controlling gas in these special conditions,which can guarantee the safety of highly efficient full-mechanized top coal caving.
