The DSC(direct self control) of speed regulation technology was applied to drive a motor running at a certain overloading ratio in intermittent working conditions.To control motor temperatures rising effectively,a fin...The DSC(direct self control) of speed regulation technology was applied to drive a motor running at a certain overloading ratio in intermittent working conditions.To control motor temperatures rising effectively,a finite element method with an iterative approach was applied to simulate real working conditions and analyze the temperature rising of the inner part of the motor.Application of DSC speed regulation realizes the invariable torque output quickly and avoids the peak current at the start state in favor of the motor temperature decreasing.Based on an analysis with the finite limit method,some effective measures were taken to improve the ability of the motor to expel heat.The overload ability of the motor was improved and the stable motor temperature rising was obtained,fulfilling the demands of electrical screw presses.展开更多
In this paper,the behavior of a salt-gradient solar pond with the square cross-section has been studied experimentally and numerically.A small-scale solar pond were designed and built to provide quantitative data.A tw...In this paper,the behavior of a salt-gradient solar pond with the square cross-section has been studied experimentally and numerically.A small-scale solar pond were designed and built to provide quantitative data.A two-dimensional,transient heat and mass transfer model has been solved numerically by using finite-control-volume method.In this study,all the thermo-physical properties are variable as the function of temperature and salt concentration.Numerical results as obtained for the experimental pond have been satisfactorily compared and validated against measured data.Furthermore,the wall shading effect has been elaborated to improve the agreement between two sets of results.The temperature of the storage zone is predicted well by the model.It also can be observed that the initial concentration profile is preserved with time.The stability of the pond in time has been investigated in order to distinguish the critical zones.Finally,the application of an energy analysis gives an efficiency of about 12%for the pond.展开更多
基金the Natural Science Foundation of Hubei Province (No.2004AA101E04)
文摘The DSC(direct self control) of speed regulation technology was applied to drive a motor running at a certain overloading ratio in intermittent working conditions.To control motor temperatures rising effectively,a finite element method with an iterative approach was applied to simulate real working conditions and analyze the temperature rising of the inner part of the motor.Application of DSC speed regulation realizes the invariable torque output quickly and avoids the peak current at the start state in favor of the motor temperature decreasing.Based on an analysis with the finite limit method,some effective measures were taken to improve the ability of the motor to expel heat.The overload ability of the motor was improved and the stable motor temperature rising was obtained,fulfilling the demands of electrical screw presses.
文摘In this paper,the behavior of a salt-gradient solar pond with the square cross-section has been studied experimentally and numerically.A small-scale solar pond were designed and built to provide quantitative data.A two-dimensional,transient heat and mass transfer model has been solved numerically by using finite-control-volume method.In this study,all the thermo-physical properties are variable as the function of temperature and salt concentration.Numerical results as obtained for the experimental pond have been satisfactorily compared and validated against measured data.Furthermore,the wall shading effect has been elaborated to improve the agreement between two sets of results.The temperature of the storage zone is predicted well by the model.It also can be observed that the initial concentration profile is preserved with time.The stability of the pond in time has been investigated in order to distinguish the critical zones.Finally,the application of an energy analysis gives an efficiency of about 12%for the pond.
