各向异性热参量对Nd:YVO4晶体热效应的影响

基于解析各向异性分析理论,研究了矩形横截面Nd:YVO4激光晶体受到具有高斯分布LD端面抽运时的激光晶体温度场分布和抽运面热形变分布.通过LD抽运Nd:YVO4激光晶体工作特点分析,建立了符合激光晶体工作状态的热模型,利用各向异性介质热传导方程的一种求解方法,得出了矩形截面Nd:YVO4晶体的温度场、热应变场和端面热形变场的通解表达式,分析了各向异性热参量对Nd:YVO4激光晶体热应变场的定量影响.研究结果表明:当使用输出功率为15 W LD端面中心入射Nd:YVO4晶体(Nd3 浓度0.5 atm%)时,在抽运端面中心获得244.9℃最高温升和1.99μm最大热形变量.     

Multistep analysis of the mechanical performance of an air spring

New methods for testing air springs have received a lot of interest in recent years. In this article APDL (ANSYS parametric design language) was utilized to simulate static and dynamic test process of air springs. In the simulation, multiple load steps solution was carried out through APDL *DO‐LOOP and array parameter method. The program (capsule volume calculating macro) based on scatter sum method enabled the loop. The scalar quantity PRESSURE was established as inner tracking parameter to update inner pressure. Table parameter PRESSURES was established as inner pressure output parameter to export inner pressure of each load step. According to rubber elastic behavior and cord‐rubber composite aeolotropy, hyper elastic element and layer element were preferred for simulation. Comparison was done between static simulation results and corresponding test data to prove feasibility of multistep analysis. In consequence, some major parameters such as cord angle, initial inner pressure, and auxiliary chamber volume were taken into account, which have remarkable effect on static mechanical performance of EQ6111 air spring. Finally, the same method was applied to the simulation of dynamic test process, achieving abundant analysis results according to every 0.5 Hz increment of load frequencies varying from 0.5 to 2.5 Hz. Load frequency threw remarkable effect on the dynamic mechanical performance of EQ6111 air spring, because inertial effect and damping effect played important roles therein. The study aims to make contribution to the development of platform of air spring simulation and parameterized design (PASSPD). © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

激光分布对抽运Nd:YVO4晶体热效应的影响

以解析各向异性分析理论为基础,研究矩形横截面Nd:YVO4激光晶体受到超高斯分布LD端面抽运时,激光晶体温度场分布和晶体抽运面热形变分布。通过激光晶体工作特点分析,考虑了激光分布和激光光束半径变化,建立了符合激光晶体工作状态的热模型。利用各向异性介质热传导方程的一种新求解方法,得出了矩形截面Nd:YVO4晶体的温度场、端面热形变场的通解表达式。研究结果表明：当使用输出功率为15W半导体激光器（超高斯阶次为1）端面中心入射Nd:YVO4晶体（晶体掺钕离子质量分数为0.5%）时,在抽运端面中心获得243.8C最高温升和1.99m最大热形变量,与实验结果一致。这种方法可以应用到其它激光晶体热问题研究中,为有效解决激光系统热问题提供了理论依据。     

叉车桥壳的拉伸缺陷分析及解决措施

从板料拉伸变形可能产生的缺陷入手 ,将传统的用2副模具拉伸的工件用1副模具成形 ,在模具结构上进行了改进 ,以保证设计目标的实现。在试模中准确地分析产生缺陷的原因 ,并予以消除