Narrow Results

The scaling problem in industrial circulating cooling water is paid more and more attention. In order to obtain bipolar alternating magnetic field, this paper presents a new device model. Moreover, aiming at the air gap flux density as high as 0.1T, we study the possibility of combining permanent magnet and rotating electric machine, then compare it with the electromagnetic generator. In addition, we study on the relationship between the magnetic induction intensity with distance and properties of two permanent magnets by using ANSYS software for magnetic field analysis. In order to realize the stepless rotation speed regulation of the single-phase asynchronous motor, an electronic speed switch was adopted, thus the alternating magnetic field frequency can also be adjusted smoothly. Through three experiments under the same conditions, we found the experimental system had experimental repeatability. Then, we carried out the experiments under alternating magnetic field with different frequencies. Experimental results showed that the alternating magnetic field had stronger inhibition effect than constant magnetic field for groups with pulse frequency as 90Hz respectively, and the highest inhibition rate reaches 33%. The scale inhibition effect of 80Hz group was the same as that of the constant magnetic field group, which indicates that not all frequencies of the alternating magnetic field have high scale inhibition effect.

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.