Although the study of TM(Thermo Mechanics),HM(Hydraulic-Mechanics) and THM(Thermo-Hydraulic-Mechanics) coupling under a loading test have been under development,rock failure analysis under THM coupling and unloading i...Although the study of TM(Thermo Mechanics),HM(Hydraulic-Mechanics) and THM(Thermo-Hydraulic-Mechanics) coupling under a loading test have been under development,rock failure analysis under THM coupling and unloading is an emerging topic.Based on a high temperature triaxial unloading seep test for phyllite,this paper discusses the deformation and failure mechanism of phyllites under the "H M,T→H,T→M" incomplete coupling model with unloading conditions.The results indicate that the elastic modulus and initial permeability decrease and the Poisson's ratio increases with increasing temperature;the elastic modulus decreases and the Poisson's ratio and initial permeability increase with increasing water pressure.During the unloading process,rock penetrability is small at the initial elastic deformation phase,but the penetrability increases near the end of the elastic deformation phase;mechanisms involving temperature and water pressure affect penetrability differently.Phyllite failure occurs from the initial thermal damage of the rock materials,splitting and softening(which is caused by pore water pressure),and the pressure difference which is formed from the loading axial pressure and unloading confining pressure.The phyllite failure mechanism is a transtensional(tension-shearing) failure.展开更多
During the start-up and shut-down phase of reciprocating compressors, the loads on all components of driven train system are very high. In this paper a method for calculating the forces on coupling, e-motor, crank sha...During the start-up and shut-down phase of reciprocating compressors, the loads on all components of driven train system are very high. In this paper a method for calculating the forces on coupling, e-motor, crank shaft as well other components of the system will be described. The modelling of the electrical induction motor, coupling, crank shaft, damper as well as the compressor resistance torque are extremely important in simulating start-up and shut-down of reciprocating compressor. Furthermore the switching torque of the electrical motor and the instantaneous moment of inertia of the reciprocating compressor crank gear are important as well. The transient start-up and shut-down process under loaded and unloaded conditions is described using a non-linear differential equation for driven train system： E-motor--coupling--flywheel--reciprocating compressor--damper. Shaft torsional moments on the drive train and especially on the coupling, whether elastic or stiff, can then only be calculated using numerical simulation. This paper will describe some of the key elements in modelling, simulating and measurements of drive train start-up and shut-down carried out on already operational piston compressor units.展开更多
基金supported by National Natural Science Foundation of China (Grant No. 41102189,No. 41002110 and No. 41230635)Projects of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Grant No. SKLGP2009Z002,No. SKLGP2009Z012)Research Fund for the Doctoral Program of Higher Education of China(Grant No. 20105122110008)
文摘Although the study of TM(Thermo Mechanics),HM(Hydraulic-Mechanics) and THM(Thermo-Hydraulic-Mechanics) coupling under a loading test have been under development,rock failure analysis under THM coupling and unloading is an emerging topic.Based on a high temperature triaxial unloading seep test for phyllite,this paper discusses the deformation and failure mechanism of phyllites under the "H M,T→H,T→M" incomplete coupling model with unloading conditions.The results indicate that the elastic modulus and initial permeability decrease and the Poisson's ratio increases with increasing temperature;the elastic modulus decreases and the Poisson's ratio and initial permeability increase with increasing water pressure.During the unloading process,rock penetrability is small at the initial elastic deformation phase,but the penetrability increases near the end of the elastic deformation phase;mechanisms involving temperature and water pressure affect penetrability differently.Phyllite failure occurs from the initial thermal damage of the rock materials,splitting and softening(which is caused by pore water pressure),and the pressure difference which is formed from the loading axial pressure and unloading confining pressure.The phyllite failure mechanism is a transtensional(tension-shearing) failure.
文摘During the start-up and shut-down phase of reciprocating compressors, the loads on all components of driven train system are very high. In this paper a method for calculating the forces on coupling, e-motor, crank shaft as well other components of the system will be described. The modelling of the electrical induction motor, coupling, crank shaft, damper as well as the compressor resistance torque are extremely important in simulating start-up and shut-down of reciprocating compressor. Furthermore the switching torque of the electrical motor and the instantaneous moment of inertia of the reciprocating compressor crank gear are important as well. The transient start-up and shut-down process under loaded and unloaded conditions is described using a non-linear differential equation for driven train system： E-motor--coupling--flywheel--reciprocating compressor--damper. Shaft torsional moments on the drive train and especially on the coupling, whether elastic or stiff, can then only be calculated using numerical simulation. This paper will describe some of the key elements in modelling, simulating and measurements of drive train start-up and shut-down carried out on already operational piston compressor units.
