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Electrostatic precipitators are large electrostatic equipment with a large volume and a complicated structure. Ash hoppers are an important component of electrostatic precipitators, making analyses of their mechanical performance of exceptional practical significance. This paper customized the finite element model according to the actual size of an ash hopper from an electrostatic precipitator, and then studied the stress field's distribution under the load effect of the ash hopper by using ANSYS. The results show that the calculation is highly accurate, and the model and calculation method produces reasonable figures. The results can be used for other structural and calculation analysis in future.

The dynamical model for a drawer structure with multi-layer printed circuit boards (PCBs) was established by the finite element method and the random vibration responses were analyzed in this paper. Firstly, the natural frequencies and their corresponding modes were obtained in terms of the finite element model of the drawer structure with PCBs. Secondly, the random vibration responses were obtained numerically for the drawer structure under random excitations. Finally, sensitive points on each layer of the drawer structure were selected to calculate the vibration responses and the acceleration power spectral density (PSD). The stress power spectral density of typical points on the PCB with high stress was also analyzed. The simulation results reveal that the largest vibration energy of the PCBs usually occurs in the middle layer of the structure and thus components in the middle of the PCBs are most likely to be destroyed.

The drum is the key part of the winch. The mechanical model of drum was established in this paper, according to the actual working condition of the winch to determine the load form and the stress analysis was carried out. The calculation results were analyzed, and the drum structure was further optimized to improve. The paper provides a reference method for design of large winch drum to meet the working performance and the quality of the drum was effectively reduced.

Focused on the differences between theoretical design and the torsional broken conditions in practical of the shearer drum's torque axis, this paper begins with simulating the field situations to paint the torque and the curve of torsion angle when the torque has been broken down. Analysis of the hardness of the fracture, microstructure, chemical composition and the finite element simulation of test procedure can determine specimen materialand calculate the difference between the actual and theoretical calculations breaking torque and finite element simulation values. The results show that, based on the differences by comparing material processing technology to determine the shear strength τ_b, different ratio coefficient k on the result of theoretical design and calculation, it is obtained correction method of the design formula by the analysis theory for modifying parameter and improving the reliability of the shaft torque.

In order to design the piezostack precision jetting dispenser applied to microelectronic packaging, ANSYS was introduced to analyze the characteristics of piezostack actuator and displacement amplifier. Firstly, the performance of the piezostack actuator when voltage increased from 0V to 200V was researched. The displacement amplifier parametric model was established and the structural parameters which define its displacement outputting were also discussed. The research indicates that triangular piece length “L0” and actuators spacing “W0” are the major parameters, the displacement changed greatly with them; but preload “F0” and diameter of bolt “D” are the minor parameters. Based upon above rules, the outputting displacement of displacement amplifier is 317μm by ANSYS simulate analysis. And then, the dynamic performance of the displacement amplifier which produced based on optimization design was tested by laser displacement sensor. The experimental results was very close to transient dynamic simulation, and error just 1.1%, which shown the validity of the simulation model. Furthermore, the experiment indicated that maximum output displacement kept the same when working frequency is between 0Hz and 65Hz, but it will drop down as frequency increase gradually. At the same time, to get the maximal displacement outputting, the controlled interval of signal duty cycle would decrease as working frequency increase.