Papers by Keyword: Modal

Abstract: In order to understand the actual working condition and the bearing capacity of the bridge, the static and dynamic tests were carried out. By measuring the stress-strain and deformation of the main control sections of the bridge, we can determine if the design expectations of the structure and its actual working performance were consistent. Through dynamic load test motivating the bridge, we got the dynamic structure factor and vibration characteristics.

Abstract: The longitudinal axis of the bridge is not perpendicular to the flow of the river and the road, skew bridges are usually used, whats more, the Stress is very complicated. Through a skew bridge static and dynamic load test, the bridges stress was analyzed, in the same way, deflection and dynamic characteristics could be analyzed. The most important was the safety performance of the bridge could be evaluated.

Abstract: Aiming at the problems of vibration and noise appeared in the work of lifting the skip underframe of the mine, a parameterized model of the underframe of skip is established by taking advantage of UG. And a finite element modal analysis is done by leading 3D model into the ANSYS, and the credibility of the finite element model is verified by combining the modal test. On the basis of comparing the characteristics of the external excitation frequency, the dynamic characteristics of the underframe of skip are evaluated and the structure is optimized. The results of the optimization indicate that: not only the modal frequency of the first eight orders of the ship underframe has avoided the range of external excitation frequency, with a smooth mode of vibration, avoiding the occurrence of sympathetic vibration effectively, but it has lost a weight of 10.6%, achieving an improvement of the hoisting capacity of the skip equipment. This research is of important reference to the technical transformation of skip equipment for some mine enterprise.

Abstract: By calculating a large span roof structures, get the intrinsic mode and real-time response of the structural under earthquake. The results showed that, the vertical acceleration response of structure is smaller than the horizontal acceleration response under EL-Centro wave and Tangshan wave. The vertical acceleration response is greater than the horizontal acceleration response under Lanzhou wave. The vertical displacement response of structure is greater than the horizontal displacement response under earthquake. Roof Destructed before the steel skeleton damage.

Abstract: Being established and assembled in UG, the model file of spur gears was imported to ANSYS workbench, where the contact between gears was built, meshing completed later. Then support and loads was imposed on the finite element model to obtain characteristics of modal and stress distribution on the teeth. After that they each were compared with working frequency and theoretically maximum contact stress and we found the fact was they fit well. By doing this, it is sound to say finite element analysis of spur gears on modal and stress is effective, feasible and reliable.

Abstract: The pre-stressed modal and random vibration of electron gun are calculated by finite element software ANSYS Workbench. The results show that electron gun under the excitation of radial load (X direction) can be in danger of disable structure. Some measures can be taken to avoid electron gun failure due to resonance, such as replacing the materials, changing the structure of weak links and changing TWT installation to make external incentives along the axial direction (Y direction). The analysis results can provide effective reference and guidance for TWT development.

Abstract: When the satellites CMG (Control Moment Gyroscope) generate the control moment, they will also generate the periodic and broadband disturbance vibration force, and will have a greater impact on the performance of instruments with high pointing precision and stability. This paper analyze a large CMG of 70Nms belonging to a remote sensing satellite, its feature is the mass of moving parts. So when it is installed to the test table that we designed independently, the fundamental frequency of the system as a whole will significantly reduce. Based on past study the purpose of this paper is mainly focused on the testing techniques of the heavy moving parts, and the technical method to isolate the test tables stiffness from test results.

Abstract: Transmission shaft is an important component of automotive transmission, parts of which are facing the problem of fatigue failure. This paper mainly analyzed the performance of the transmission shaft based on finite element method. Firstly, stress contour is obtained of the shaft. secondly, get the fatigue performance according to material S-N curve. Finally, The dynamic characteristics including vibration modal and frequency response are analyzed. The results can provide reference for dynamic design of transmission shaft , as well as the structure optimization design of the transmission shaft .

Abstract: In order to have comprehensive understanding and better application about Modal fibers, the microstructure of Lenzing Modal (MD), Birla Modal (BLM) and Formotex Modal (FM) siro-spun yarn was investigated by XRD and FTIR spectroscopy. The tensile properties of the yarn were measured by an Instron tensile tester, the hairiness and boiling shrinkage of the three kinds modal siro-spun yarn were also investigated. The results indicate that the main chemical component of the three kinds of modal yarn are all cellulose. However, the MD shows a higher crystallinity and breaking tenacity when compares with BLM and FM. All the three kinds of modal siro-spun yarn show excellent applied properties, the hairiness and boiling shrinkage of the three kinds of yarn are small.

Abstract: An accurate three-dimensional flow passage model of the compressor has been created; the stress distribution of the main flow channel has been obtained. The aerodynamic force was applied to the impeller blades. Three kinds of loads were applied to the main blades and splitter blades. Modal characteristics of the compressor blades have been intensively studied.