Applied Mechanics and Materials Vols. 201-202

Abstract: A straightness measurement device for theqitade haishi FD slider’s motion of the press is presented. The design uses eddy current sensors, which will accomplish the measurement of straightness in un-contacted ways. MCU takes charge of data process. The straightness error can be calculated by the arithmetic of mean value. A straightness evaluation system is constructed as well. This device changes the traditional way of straightness measurement which is measured by the dial indicator. And it can improve the efficiency of straightness measuring task

Abstract: Aimed at the welding initial defect fatigue extension of 300t converter loop in a factory, the whole assembly finite-element (FE) model of converter loop with the welding initial defect is established. The converter loop FE model with different depth initial defect is computed by using 3D nonlinear finite element method at different tilting angles. And the stress intensity factor is extracted and analyzed under different working circumstances. The analysis results show that when the initial defect depth is greater than 11.715mm, the defect will result in fatigue crack extension at the complex alternating stress. To solve the cracking leakage problem of converter loop, the original welding manholes is replaced by the movable manhole. In the past over one year, the fatigue cracking and leaking phenomena did not occur in the converter loop, so the effect is obvious.

Abstract: This paper aims to design an ultrasonic cleaning machine for crops to provide the engineers with very useful information. First, the new practical model is designed, including the body shell, cleaning tank, ultrasonic generator and control system. Second, three vegetables (lettuce, cabbage and potato) are used in the experiment. The result shows the damage percentage after washed was 0%. The root vegetables are cleaned faster in this machine.

Abstract: Have a large population because of being engaged in tennis, impact in ball and bat in the energy transfer produced, only some energy is changed into the kinetic energy that the ball rebounded, other energy will be consumed in the vibration of the ball, network thread and frame, among them the arm that the vibration of the frame certainly will be held bat by the human body is absorbed, load to cause arm produce tired to injure, certainly will absorb through bat transmission of bar by human body even, excessive load, cause arm weariness and strain, it is thereupon production to injure, probing into the vibration quality of bat becomes the very urgent theme, so this text aims at studying and striking the regional impact on vibration characteristic of tennis racket differently. Research this through experiment analytic approach, by accelerate rule amount of instrument and equipment waited for examine different to bump into area hold bat, take things vibration energy parameter on bat. This research obtains the important conclusion as follows: 1. In the impacting experiment of tennis racket, include driving board mode and node bending mode. 2. The natural frequency between 117Hz and 127Hz, amplitude and bending type that produce its have extensive, influence to arm. 3. The impacting area on the throat area, the vibration energy that the arm bears is biggest, secondly for the side area next for the tip area, it is the sweet district is minimum, so try not to deviate from the sweet districts in the batting area.

Abstract: In order to obtain the real-time working state of machine tools, this experiment extracted the characteristics of machine tools using joint time-frequency analysis and wavelet packet analysis for the total current signal collected, to distinguish which machine is running. First, use joint time-frequency analysis on signal of a single machine to get different characteristics. And find some frequency points with amplitude changing significantly, preparing for the subsequent experiment. Then use wavelet packet analysis on the total signal of more than one machine, finding more obvious characteristics of the different machines with different speeds. Thus it is easy to identify which machine is working. By this experiment, we can save labor, improve efficiency and integrate information in system conveniently.

Abstract: The characteristics of traditional vacuum cleaner and automatic cleaning robot are analyzed in the paper. A new device for household cleaning is designed. The device combines leaning mechanism with suction mechanism. It could work only by pushing the cleaning machine. In its working process, the cleaning mechanism cleans larger litters first, and then the acceleration mechanism drives the impeller rotating at a high speed, and thus produces negative pressure to inhale the remaining dust. The device could improve cleaning efficiency. As the dust suction mechanism only needs to inhale dust, the force could be smaller .It will saves power and reduces the noise generated by the vacuum part at the same time.

Abstract: In this paper, the experiment of thin-walled square beam subject to three-point bending by using the self-devised drop-hammer impact was carried out. The mechanical behavior of this thin-walled specimen under impact load was obtained. The process of deformation and the dynamic buckling behaviors of composite square beam were analyzed by mean of simulation technique of finite element using ANSYS/LS-DYNA. The simulation analysis of deformation and crushing force characteristics was in good agreement with the experimental results. Meanwhile, the comparative analysis of percussive force and energy absorbability from composite beam and single beam was performed. It is shown by the investigation that the peak percussive force of such composite beam falls down relative to single beam and it possesses good energy absorbability too. The computed result also shows reducing the thickness of the bottom board of such thin-walled square beam has less of an effect on the energy absorbability.

Abstract: The Parallel Finite Element Analysis Software ANSYS is used for transient dynamics of self-anchored suspension bridge. The paper studies influence on structure transform under a lotus function and frequency of self-anchored suspension bridge, vehicle together to drive to influence a little bit greatly towards self-anchored suspension bridge structure, difference drive to Self-anchored Suspension Bridge the structure influence smaller, VonMises stress of Suspension Bridge medium node will decrease, when angle frequencies augment, conclusions have instruction function to Self-anchored Suspension Bridge design and construction.

Abstract: Human bone should be individualized modeled and manufactured because of its complex shapes and individual differences. Based on CT tomography images, defect human bone outline was individualized modeled. The technologies of computer image-processing techniques, computer graphics and computer aided geometric design were used in the paper. Also the software of MIMICS was used for medical image-processing. The softwares of Geomagic Studio and UG were used to realize 3D modeling of individualized artificial bone outline and solid modeling in the technology. The results showed that the 3D model met the requests completely, and provided a foundation for the following individualized manufacturing.

Abstract: A two-dimensional numerical computation was carried out for two cylinders in tandem changing unsteady flow regime. Mechanisms of heat transfer enhancement due to tandem two cylinders in unsteady flow were discussed based on the obtained flow and thermal fields. The simulation result shows that the center distance of two cylinders is the main factor of heat transfer enhancement. It also shows that the wake of the upstream cylinder acts periodically the near wall of the downstream cylinder and the tip of vortices plays an important role on the leading edge of the downstream cylinder. Base on the numerical results, it is observed that there locally exists the dissimilarity between the momentum transfer and heat transfer, which was related to the hot or cold fluid.