A two-dimensional axisymmetric finite element model is developed to analyze the transient thermal and mechanical behaviors of the Resistance Spot Welding (RSW) process using commercial software ANSYS. Firstly a dire...A two-dimensional axisymmetric finite element model is developed to analyze the transient thermal and mechanical behaviors of the Resistance Spot Welding (RSW) process using commercial software ANSYS. Firstly a direct-coupled electrical-thermal Finite Element Analysis (FEA) is performed to analyze the transient thermal characteristics of the RSW process. Then based on the thermal results a sequential coupled thermo-elastic-plastic analysis is conducted to determine the mechanical features of the RSW process. The thermal history of the whole process and the temperature distribution of the weldment are obtained through the analysis. The mechanical features, including the distributions of the contact pressure at both the faying surface and the electrode-workpiece interface, the stress and strain distributions in the weldment and their changes during the RSW process, the deformation of the weldment and the electrode displacement are also calculated.展开更多
文摘针对膜下滴灌种植过程中外界水压变化造成的变频器过载现象,设计了一种棉田水肥一体化控制系统。系统以三菱FX2N PLC为核心,能够实时监测外部水压,依据外部水压的变化量和水肥调整函数关系式,优化水肥溶液排量设定值,保证施肥过程中PID闭环控制系统的稳定运行。使用Samkoon AK 070 MG触摸屏搭建了物联网云平台,完成了开机界面、手动控制界面、自动控制界面、历史数据界面、动态监控界面和触摸屏远程监控界面的编写,可以直观地查询设备的实时运行参数。试验结果表明:当系统水压为0.1~0.4MPa、变频器初始设定频率为35Hz时,可以实现施肥频率的自调整和施肥流速的稳定输出,提高了水肥利用效率,保证了设备的高效运行。
文摘A two-dimensional axisymmetric finite element model is developed to analyze the transient thermal and mechanical behaviors of the Resistance Spot Welding (RSW) process using commercial software ANSYS. Firstly a direct-coupled electrical-thermal Finite Element Analysis (FEA) is performed to analyze the transient thermal characteristics of the RSW process. Then based on the thermal results a sequential coupled thermo-elastic-plastic analysis is conducted to determine the mechanical features of the RSW process. The thermal history of the whole process and the temperature distribution of the weldment are obtained through the analysis. The mechanical features, including the distributions of the contact pressure at both the faying surface and the electrode-workpiece interface, the stress and strain distributions in the weldment and their changes during the RSW process, the deformation of the weldment and the electrode displacement are also calculated.