Aiming at the problem of temperature rise of mine flameproof outer rotor permanent magnet synchronous motor,based on the fluid structure coupling method,the temperature distribution of motor under three cooling scheme...Aiming at the problem of temperature rise of mine flameproof outer rotor permanent magnet synchronous motor,based on the fluid structure coupling method,the temperature distribution of motor under three cooling schemes of air cooling and water cooling are calculated respectively.For the structure I air cooling system,the influence of different number of heat sink on the maximum temperature rise and pressure drop of fluid channel is analyzed,and the parameters of heat sink are optimized.For the structure II air cooling system,the influence of setting fillet at the turn back of the fluid channel on the head loss in the fluid domain of the motor is analyzed,and the influence of different fillet radius on the head loss and the maximum temperature rise in the fluid domain is obtained.For the structure II water cooling system,the influence of different water flow speed on the maximum temperature rise of the motor is analyzed,and the influence of different assembly clearance of modular stator teeth and yoke on the maximum temperature rise of the motor is analyzed.The cooling effect and temperature rise distribution characteristics of the three cooling schemes are compared and analyzed.Finally,a water-cooled prototype is manufactured,and the temperature rise experiment is carried out,and the influence of the thermal deformation of fluid channel,stator yoke and stator teeth on the maximum temperature of the motor is analyzed.The results show that the calculated temperature field after considering the thermal deformation is closer to the experimental value,which verifies the accuracy of the calculation results,It also provides a reference for the selection and design of the cooling structure of the same type of PMSM electric roller.展开更多
The efficiency and precision of parameter calibration in discrete element method （DEM） are not satisfactory, and parameter calibration for granular heat transfer is rarely involved. Accordingly, parameter calibratio...The efficiency and precision of parameter calibration in discrete element method （DEM） are not satisfactory, and parameter calibration for granular heat transfer is rarely involved. Accordingly, parameter calibration for granular heat transfer with the DEM is studied. The heat transfer in granular assemblies is simulated with DEM, and the effective thermal conductivity （ETC） of these granular assemblies is measured with the transient method in simulations. The measurement testbed is designed to test the ETC of the granular assemblies under normal pressure and a vacuum based on the steady method. Central composite design （CCD） is used to simulate the impact of the DEM parameters on the ETC of granular assemblies, and the heat transfer parameters are calibrated and compared with experimental data. The results show that, within the scope of the considered parameters, the ETC of the granular assemblies increases with an increasing particle thermal conductivity and decreases with an increasing particle shear modulus and particle diameter. The particle thermal conductivity has the greatest impact on the ETC of granular assemblies followed by the particle shear modulus and then the particle diameter. The calibration results show good agreement with the experimental results. The error is less than 4%, which is within a reasonable range for the scope of the CCD parameters. The proposed research provides high efficiency and high accuracy parameter calibration for granular heat transfer in DEM.展开更多
基金This work has been supported by the National Natural Science Foundation of China(51907129)Project Supported by Department of Science and Technology of Liaoning Province(2021-MS-236).
文摘Aiming at the problem of temperature rise of mine flameproof outer rotor permanent magnet synchronous motor,based on the fluid structure coupling method,the temperature distribution of motor under three cooling schemes of air cooling and water cooling are calculated respectively.For the structure I air cooling system,the influence of different number of heat sink on the maximum temperature rise and pressure drop of fluid channel is analyzed,and the parameters of heat sink are optimized.For the structure II air cooling system,the influence of setting fillet at the turn back of the fluid channel on the head loss in the fluid domain of the motor is analyzed,and the influence of different fillet radius on the head loss and the maximum temperature rise in the fluid domain is obtained.For the structure II water cooling system,the influence of different water flow speed on the maximum temperature rise of the motor is analyzed,and the influence of different assembly clearance of modular stator teeth and yoke on the maximum temperature rise of the motor is analyzed.The cooling effect and temperature rise distribution characteristics of the three cooling schemes are compared and analyzed.Finally,a water-cooled prototype is manufactured,and the temperature rise experiment is carried out,and the influence of the thermal deformation of fluid channel,stator yoke and stator teeth on the maximum temperature of the motor is analyzed.The results show that the calculated temperature field after considering the thermal deformation is closer to the experimental value,which verifies the accuracy of the calculation results,It also provides a reference for the selection and design of the cooling structure of the same type of PMSM electric roller.
基金Supported by National Natural Science Foundation of China(Grant Nos.51105092,61403106)International Science and Technology Cooperation Program of China(Grant No.2014DFR50250)the 111 Project,China(Grant No.B07018)
文摘The efficiency and precision of parameter calibration in discrete element method （DEM） are not satisfactory, and parameter calibration for granular heat transfer is rarely involved. Accordingly, parameter calibration for granular heat transfer with the DEM is studied. The heat transfer in granular assemblies is simulated with DEM, and the effective thermal conductivity （ETC） of these granular assemblies is measured with the transient method in simulations. The measurement testbed is designed to test the ETC of the granular assemblies under normal pressure and a vacuum based on the steady method. Central composite design （CCD） is used to simulate the impact of the DEM parameters on the ETC of granular assemblies, and the heat transfer parameters are calibrated and compared with experimental data. The results show that, within the scope of the considered parameters, the ETC of the granular assemblies increases with an increasing particle thermal conductivity and decreases with an increasing particle shear modulus and particle diameter. The particle thermal conductivity has the greatest impact on the ETC of granular assemblies followed by the particle shear modulus and then the particle diameter. The calibration results show good agreement with the experimental results. The error is less than 4%, which is within a reasonable range for the scope of the CCD parameters. The proposed research provides high efficiency and high accuracy parameter calibration for granular heat transfer in DEM.
