Advanced Materials Research Vols. 915-916

Abstract: Three dimension finite element analysis and full-scale testing are carried out on a newly-built continuous beam arch composite bridge. The 3D finite element model of the bridge is generated using a commercially available finite element package. The bridge is modeled under service loads, and the model results are compared to the results of field testing of the structure. Detailed experimental procedure is presented including the data acquisition system, testing truck, and the load distribution. Measured and calculated displacements are in reasonable concordance. And residual deformations meet the specification of the codes.

Abstract: The objective of the present work is to evaluate the static and dynamic stability of the Flying Wing Unmanned Aircraft Vehicle (UAV) model using the Tornado software. The longitudinal and the lateral-directional aerodynamics were studied using the model with incompressible flow, asymmetric, conditions. The stability coefficients were calculated and give proof that the aircraft is statically stable. Using the stability coefficients, the longitudinal and lateral-directional equations of motion were written to evaluate the dynamic stability of the vehicle. Good flying qualities were obtained, rating in Level 1 for the Cooper and Harper scale.

Abstract: Drilling string lateral vibration is a severe damage,which is influenced by many complex factors. This paper makes a theoretical analysis of the drilling string lateral vibration frequency caused by drilling fluid flow velocity inside and outside the drilling string, which supplies some evidence for calculating rotation speed of rotary table and reduces the times of drill string resonance. The influence of drilling fluid flow velocity inside the drilling string on lateral vibration frequency is analyzed by Euler method. Besides, through the use of mechanical analysis method and the introduction of additional mass coefficient. A differential equation of drilling string lateral vibration with the consideration of drilling fluid flow velocity inside and outside the drilling string is built up, and a mathematical model of drilling string lateral vibration under the influence of drilling fluid flow velocity is obtained. Field applications indicate that this model is in agreement with the field condition.

Abstract: The main causes of the ground motion blind prediction bias are the variability of the adopted program, the shear-wave velocity of the site, and the soil nonlinear dynamic parameters. By considering the variability of shear-wave velocity and the dynamic parameters, this essay used LSSRLI-1 Codes and M_w6.0 seismic record of Parkfield earthquake to calculate ground responses of 9 different conditions at Turkey Flat site. The authors believe that the variability of shear-wave velocity caused the dominant impact to the blind prediction of this shallow stiff-soil site. That impact is much greater than that of the dynamic parameters. LSSRLI-1 program may either underestimate the ground response of the shallow stiff-soil site or may overestimate it, so we should combine the specific site conditions and a large amounts of data to do the further analysis.

Abstract: The torsional vibration problems of turbo-generator shafts are increasing widespread and sever under the coupled action between the turbo-generator unit and the power grid because of the complicated power grid structure. Thus, the accurate solution of torsional vibration inherent characteristics of the shafts is of great significance to do the safety evaluation. The finite element method (FEM) with higher accuracy is adopted to calculate the torsional vibration inherent characteristics in this paper. A 1000 MW turbo-generator shaft is taken as a studying object and its torsional vibration finite element (FE) model and solving process are introduced, using ANSYS software as implementation platform of the FEM. The simulation results show that the torsional vibration characteristics calculated by FEM are accurate and reliable.

Abstract: Put forward a kind of based on B/S three layer architecture model of cutting parameter database system, the establishment of a complete effective cutting data model used to describe the dynamics simulation optimization of the parameters in the software and the other elements in the process of cutting.At the same time, the establishment of a database contact dynamics simulation optimization software, realized the database support for the typical dynamic simulation optimization software, the development of the corresponding database management system, and completed the cutting data transfer between different data structure.

Abstract: Vibration is one of the most important problems in laser cutting machine tool, which causes the manufacturing errors, also influences the machining accuracy of the parts. Modal analysis can calculate vibration type of structures. The paper presents how to use the powerful FEA software ANSYS to do the modal analysis on laser cutting machine tool and also studies the undamped free vibration on laser cutting machine tool. Finally, the test results and theoretical results were compared to verify the rationality of the modal, these provide theoretical base and conditions for dynamics analysis and optimal design.

Abstract: Dynamic simulation study on Morse CVT input mechanism was established by using software Adams, and it can get curves of displacement, velocity and acceleration of each bar and the torque of input mechanisms output in order to research its dynamic characteristics. This method is suitable for dynamic simulation of connecting rod mechanism, meanwhile it is easy to do optimal design by amending corresponding simulation parameter.

Abstract: In order to decrease the maintain cost and simplify the operation process of the frame of garbage transferring vehicle, a new scheme of vertical transferring frame of garbage container is provided, and the unloading process of the frame is given. The prototype model of the vehicle frame in unloading process is built. The simulated curve of the displacement of the lifting hydraulic cylinder and the turning angle of frame is accord with the theoretical computed one. By running the dynamic model, the dynamic curve of the force of the lifting hydraulic cylinder, the force of the sliding hydraulic cylinder, the force of the lug on sliding frame acted to container and the force of ground acted to container are obtained, which provide basis on designing the structure of the frame.