一种新型的深孔负压装置研究

通过对现有DF深孔钻削系统的结构及工作原理的理论分析,研究新型双锥面负压射流结构、负压机理及排屑特性,提供一种排屑能力更强、工艺性更好、加工精度和生产效率更高、孔径实用范围更广的新型深孔双锥面负压装备,应用于ZK2138深孔钻床,结合理论分析,进行正交化设计试验,最终确定新型双锥面负压射流通道的合理几何参数.     

DF系统喷射泵的研究

对DF系统喷射泵的流体力学特性进行分析,并构建数学模型。通用流体力学软件FLUENT对DF系统中的喷射泵进行了力学仿真。     

旋转DF系统的多结构参数建模及结构设计

针对深孔加工中排屑难、效率低的问题,设计出一种具有刀具旋转功能的DF钻削系统。基于流体力学理论建立了深孔机床DF系统的多结构参数数学模型,揭示了主要结构参数对负压抽屑效果的影响规律,获取了最佳的参数组合。进一步地,对现有旋转DF系统进行了结构完善及参数优化。研究结果为深孔机床抽屑装置的优化设计提供了可借鉴的方法。     

DF深孔钻削技术及其负压抽屑系统

本文概述了DF钻削技术的优点,简要阐述了DF深孔钻负压抽屑作用的机理,介绍了影响负压抽屑效果的实验数据和规律,对于DF钻削技术的推广应用有参考价值。     

深孔加工脉冲负压排屑装置的设计研究

深孔DF系统的负压排屑装置采用恒压供油,易产生堵屑现象.针对此问题,设计了一种脉冲式供油装置,建立了该装置的脉冲流体数学模型.基于FLUENT软件对脉冲式供油时,不同射流速度产生的负压效果进行了仿真试验,得出了脉冲式供油能使排屑通道中产生不断变化的负压值.研究结果表明:基于负压排屑理论设计的脉冲负压排屑装置能有效改变排...     

深孔加工可转动负压抽屑装置的研究与设计

针对大尺寸和形状复杂的零件,在深孔加工过程中,采用传统的工件转动,刀具进给已经不能满足加工需求。采用刀具旋转进给,工件静止的加工工艺在现代深孔加工技术中显得很有必要。通过对现有DF深孔钻削系统的结构及其工作原理进行理论分析,对负压抽屑装置进行改进,设计出可转动负压抽屑装置,从而更好地满足实际生产的需要。     

DF系统的简易设计与应用

本文从使用的角度出发,简化了DF系统的设计及复杂的微分方程计算公式,并阐述了在总结实践经验的基础上,将它推广到一般内排屑钻镗孔、前排屑推镗及高速拉铰等3种深孔加工方式的方法。一、基本原理与简易计算公式“DF系统”是一种先进的深孔加工方式,就是存深孔钻床上的双向加油,喷吸流量调节系统。它包括固定在机床上的喷吸机构与各种规格的,按计算结果制造出来的,带有反压间隙控制凸环的内排屑钻头(即DF钻)。这门新技术,在工业发达的国家已普遍应用     

深孔DF系统脉冲排屑机理的研究

针对深孔DF系统采用恒定供油方式,排屑效率受到影响的问题,在DF系统排屑机理的研究基础上,提出脉冲供油排屑方式,实验不同脉冲供油频率下的切削液流量变化信号;分析流量变化数据,得到脉冲效果最佳的频率参数;基于Fluent软件对采用脉冲供油排屑方式时的流体特性进行仿真实验,得出脉冲式供油能够增强排屑过程中的冲击、扰动效果,...     

深孔钻削双锥面负压系统研究

通过对现有DF深孔钻削系统的结构及工作原理的理论分析,研究新型双锥面负压射流结构、负压机理及排屑特性,提供一种排屑能力更强、工艺性更好、加工精度和生产效率更高、孔径实用范围更广的新型深孔钻削双锥面负压装备,应用于ZK2138深孔钻床,结合理论分析,进行正交化设计试验,最终确定新型双锥面负压射流通道的合理几何参数.     

吸入特性测试装置的机械系统设计

为了研究大口径活塞泵对高浓度粘稠物料吸入容积效率,自行设计了吸入特性测试装置,简要阐述了机械系统的工作原理,详细介绍了物料缸、活塞、液动闸板阀等主要组成部分的功能与设计,最后简单介绍了测试装置的应用情况.     

基于FLUENT的水阀内置流量传感器设计及流场仿真

建立了轴流式叶轮流量传感器工作时的流体数学模型,对水阀内置流量传感器进行了结构设计,并在分析了传统涡轮流量传感器结构基础上提出了改进意见.利用CFD软件FLUENT对所设计的流量传感器进行了流场仿真,为该传感器进一步优化提供了参考.     

数控G代码编译器的设计与研究

由于PC机具有通用性好,价格便宜,互换性好,体系结构开放等优点,发展基于PC的数控系统已成为世界各国发展研究的重点.     

氟化氘高能激光系统中的光学薄膜

报道了氟化氘(DF)激光系统腔镜高反射膜、CaF2窗口红外宽带增透膜和共孔径分光镜的研制,并介绍了DF腔镜高反射膜的热畸变和损伤实验测试结果.实验结果表明,DF腔镜高反射膜的损伤阈值大于100kW/cm2,CaF2窗口红外宽带增透膜和共孔径分光镜均经受了200kW激光功率的输出,达到了总体提出的要求.     

氟化氘高能激光系统中的光学薄膜

报道了氟化氘(DF)激光系统腔镜高反射膜、CaF2窗口红外宽带增透膜和共孔径分光镜的研制,并介绍了DF腔镜高反射膜的热畸变和损伤实验测试结果.实验结果表明,DF腔镜高反射膜的损伤阈值大于100kW/cm2,CaF2窗口红外宽带增透膜和共孔径分光镜均经受了200kW激光功率的输出,达到了总体提出的要求.     

氟化氘高能激光系统中的光学薄膜

报道了氟化氘 ( DF)激光系统腔镜高反射膜、Ca F2 窗口红外宽带增透膜和共孔径分光镜的研制 ,并介绍了 DF腔镜高反射膜的热畸变和损伤实验测试结果。实验结果表明 ,DF腔镜高反射膜的损伤阈值大于 1 0 0 k W/cm2 ,Ca F2 窗口红外宽带增透膜和共孔径分光镜均经受了 2 0 0 k W激光功率的输出 ,达到了总体提出的要求。     

基于FLUENT的采棉机输棉系统内部流场的模拟研究

介绍了FLUENT软件的主要特点、采棉机输棉系统的基本工作原理及其FLUENT在采棉机输棉系统中的应用情况,并以某一型号的采棉机输棉系统为例,用该软件进行建模、网格划分和数值模拟,在模拟结果中截取压力和速度分布图,进而分析输棉管道内流场的分布和变化情况。通过这种模拟,不仅能得出采棉机输棉系统的整体性能,而且能发现输棉管道内部流场的许多流动细节和现象,从而可获得影响采棉机输棉系统的规律性的因素,为改进设计,提高输棉管道性能提供了重要的途径和方向。     

高分辨率快速成形系统运动精度研究

快速成形系统升降工作台的运动精度是成形系统实现高精度制作的基础,对高分辨率激光快速成形系统的升降工作台运动精度进行测试研究.测试结果表明:工作台定位精度为6.4μm,单向重复定位精度为6.4μm,达到设计要求.还对工作台在向上进给和向下进给过程中,单向定位系统偏差及单向重复定位精度有明显差异的问题进行了研究,发现工作台的受力状态不同是出现以上问题的主要原因.     

A study on cooling efficiency using 1-d analysis code suitable for cooling system of thermoforming

Thermoforming is one of the most versatile and economical processes available for polymer products, but cycle time and production cost must be continuously reduced in order to improve the competitive power of products. In this study, water spray cooling was simulated to apply to a cooling system instead of compressed air cooling in order to shorten the cycle time and reduce the cost of compressed air used in the cooling process. At first, cooling time using compressed air was predicted in order to check the state of mass production. In the following step, the ratio of removed energy by air cooling or water spray cooling among the total removed energy was found by using 1-D analysis code of the cooling system under the condition of checking the possibility of conversion from 2-D to 1-D problem. The analysis results using water spray cooling show that cycle time can be reduced because of high cooling efficiency of water spray, and cost of production caused by using compressed air can be reduced by decreasing the amount of the used compressed air. The 1-D analysis code can be widely used in the design of a thermoforming cooling system, and parameters of the thermoforming process can be modified based on the recommended data suitable for a cooling system of thermoforming. This paper was recommended for publication in revised form by Associate Editor Dongsik Kim Zhen-Zhe Li received his B.S. degree in Mechanical Engineering from Yanbian University, China, in 2002. He then received his M.S. degree in Aerospace Engineering from Konkuk University, South Korea, in 2005. He then received his Ph.D. degree in Mechanical Engineering from Chonnam National University, South Korea, in 2009. Dr. Li is currently a Researcher of the Department of Mechanical Engineering, Chonnam National University, South Korea. Dr. Li’s research interests include applied heat transfer, fluid mechanics and optimal design of thermal and fluid systems. Kwang-Su Heo received his B.S. degree in Mechanical Engineering from Chonnam National University, South Korea, in 1998. He then received his M.S. and Ph.D. degrees in Mechanical Engineering from Chonnam National University, South Korea, in 2003 and 2008, respectively. Dr. Heo is currently a Post-doctorial Researcher of the Department of Mechanical Engineering, KAIST(Korean Advanced Institute of Science and Technology), South Korea. Dr. Heo’s research interests include applied heat transfer, fluid mechanics and thermal analysis of superconductor. Dong-Ji Xuan received his B.S. degree in Mechanical Engineering from Harbin Engineering University, China, in 2000. He then received his M.S. degree in Mechanical Engineering from Chonnam National University, South Korea, in 2006. He is currently a Ph.D. candidate of the Department of Mechanical Engineering, Chonnam National University, South Korea. His research interests include control & optimization of PEM fuel cell system, dynamics & control, mechatronics. Seoung-Yun Seol received his B.S. degree in Mechanical Design from Seoul National University, South Korea, in 1983. He then received his M.S. degree in Mechanical Engineering from KAIST(Korean Advanced Institute of Science and Technology), South Korea, in 1985. He then received his Ph.D. degree in Mechanical Engineering from Texas Tech University, USA, in 1993. Dr. Seol is currently a Professor of the School of Mechanical and Systems Engineering, Chonnam National University, South Korea. Dr. Seol’s research interests include applied heat transfer, fluid mechanics and thermal analysis of superconductor.