Journals
  Publication Years
  Keywords
Search within results Open Search
Please wait a minute...
For Selected: Toggle Thumbnails
Study on Transverse Impact Characteristics of Flexible Rubber Pipe Joint
SHAO You-hua;ZHANG Zhen-hua
   2012, 32 (1): 149-153.   DOI: 10.3969/j.issn.1006-1355-2012.01.035
Abstract （1712）            Save
The transverse impact characteristics of a flexible rubber pipe joint are studied. A pair of joints assembled end-to-end with an inserted middle mass was tested in a drop shock testing machine. Based on the test results, an equivalent beam model with fixed-ends and polynomial varying stiffness and damping was applied to predict the transverse impact response and identify the nonlinear impact parameters. The least square residual between the computed and tested results was chosen as the target to perform the identification optimization. The results show that the equivalent bending stiffness of the flexible rubber pipe joint gradually decreases with the increasing of the transverse deformation and is greatly influenced by its internal working pressure.
Related Articles | Metrics
Subjective Vibration Evaluation and Modal Testing for the Overhead Guard of a Forklift Truck
XU Chang;Yan Tian-hong;ZHANG Zhen
   2012, 32 (1): 77-80.   DOI: 10.3969/j.issn.1006-1355-2012.01.018
Abstract （1709）            Save
In this paper, the vibration of the overhead guard of a forklift is diagnosed. Firstly, the vibration signals are collected when the forklift is operating, and the signals corresponding to the worst subjective evaluation of comfort are extracted and analyzed. Then, the modal test of the overhead guard of the forklift is conducted, and the results are compared with the vibration signals corresponding to the worst comfort. It is found that the main reason of the forklift vibration which leads to the worst comfort is the resonance of the overhead guard excited by the engine. Since the modals of the overhead guard structure in the vicinity of the resonance frequency are very close one another, successive resonance will occur in the acceleration period, which is a serious impact on the comfort of the forklift. Finally, a scheme for reducing the vibration is proposed. A correlation between objective measurements and subjective evaluation is found by means of the proposed approach. This work supplies references for the vibration isolation design.
Related Articles | Metrics
Modal Analysis and Model Updating of Optical Element
SHAO Jun;YE Jing-feng;HU Zhi-yun;ZHANG Zhen-rong;HUANG Mei-sheng
   2012, 32 (1): 39-42.   DOI: 10.3969/j.issn.1006-1355-2012.01.009
Abstract （1485）            Save
To study the dynamic performance of optical elements, the modal experiment for an optical mirror mount was carried out as an example. Its dynamic computation model was established and its reliability was verified. And the modal analysis was done. To reduce the deviation between the theoretical model and practical situation, the dynamic computation model was updated from time to time by analyzing the relative sensitivity of the frequency to the model parameters such as material property, Poisson ratio, elastic modulus, geometrical dimensions and so on. Then the most sensitive parameter was found, and the model was updated according to this parameter. It is found that the dynamic characteristics of the updated model is closer to the measurement data, and the frequency deviation between the simulation and measurement is obviously reduced. Results show that the dynamic computation model is capable for describing the dynamic characteristics of the optical elements.
Related Articles | Metrics
Modal Test and Vibration Analysis of the Optical Element with Different Boundary Constraint Conditions
SHAO Jun;YE Jing-feng;HU Zhi-yun;ZHANG Zhen-rong
   2011, 31 (6): 165-168.   DOI: 10.3969/j.issn.1006-1355-2011.06.037
Abstract （1500）            Save
To analyze and evaluate anti-vibration performance of the optical element, a series of modal experiments about the L-shaped pad element with different boundary constraint conditions is carried on. Firstly, the deviation of the results from ANSYS simulation and measurement is limited in an allowable range, so that the definition of modal performance and the reliability of experiments of the model are validated. Secondly, anti-vibration performance of optical element is analyzed based on the experiments data, and the modal parameters of the element with different boundary conditions are obtained. Finally, the working stability of the element with different assembly situation is analyzed according to the different dynamic characteristics under different boundary constraint conditions. This work may provide a reference for improving the anti-vibration and working performances of optical elements in different environments.
Related Articles | Metrics
Study on Vibration of Multiple-deformable-body System
JIN Jing;ZHANG Zhen-shan;XIONG Xin
   2011, 31 (6): 43-46.   DOI: 10.3969/j.issn.1006-1355-2011.06.010
Abstract （1506）            Save
On the base of vibration study of single-deformable-body system and the dynamic theory of multi- deformable-body system, vibration response of a mechanical system including multiple deformable bodies is analyzed. First of all, a crankshaft-piston mechanism is taken as a representation, and its dynamic model is created and analyzed by ANSYS and ADAMS codes. And then, the basic relations between the deformable-bodies and the system’s vibration response are obtained. These relations can provide a necessary reference for simplifying the vibration model of the large system and ensuring the precision of computation.
Related Articles | Metrics