共查询到20条相似文献,搜索用时 234 毫秒
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为解决低温风洞试验模型加工周期长、刀具磨损严重、工件易变形等问题,通过采用国产18Ni(200)低温钢材加工二元翼型和支杆模型,对影响模型加工质量、效率和成本的刀具类型、切削速度、进给量、切削深度、打磨方法等工艺参数进行选型和优化,得到了加工该种材料模型的最优工艺参数组合及流程。通过加工大展弦比半模机翼模型,验证了工艺优化结果的可靠性,给出了该类长薄构型部件加工变形控制的方法和建议。 相似文献
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通过分析目前三维环境下工艺设计存在的问题,在工艺设计过程中引入工序模型的概念,并提出了工序模型驱动的工艺设计方法.该方法从零件设计模型到毛坯模型逆向生成零件的加工工序,每规划一道工序,生成一个工序模型,然后基于该工序模型进行下一道工序的规划.在工序模型驱动的工艺设计过程中,加工特征识别、加工元生成以及加工元聚类是影响工艺自动规划的关键,为此,对基于工序模型的混合加工特征识别、基于知识的加工元生成以及基于模糊C-均值的加工元聚类进行了深入的研究.以某型号飞机双面大框零件为例,讨论了所提方法的应用过程,为三维环境下的工艺设计提供了一种新思路. 相似文献
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基于三维零件模型的工艺路线设计方法研究 总被引:3,自引:1,他引:2
针对基于三维CAD的计算机辅助工艺设计(Computer Aided Process Planning,CAPP)的发展需求,提出了一种基于三维零件模型的工艺路线设计方法。从零件三维模型中提取加工特征,建立以加工特征为核心的工艺信息模型,有利于与上游CAD以及下游CAM的集成和信息共享。在工艺信息模型基础上建立以加工元为基元的工艺决策模型,通过聚类和排序约束实现工序/工步的确定和排序,实现工艺决策过程的算法化。通过飞机双面大框零件实例说明了该方法是简单有效的。 相似文献
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航空发动机齿轮是飞机的关键零部件,其加工精度是航空发动机可靠性、高性能的重要保证,直接影响着航空发动机的整体质量针对齿轮加工的几种常用方法.提出了提高齿轮加工精度的具体方法和建议. 相似文献
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《机械工程学报》2014,(19)
正项目负责人:梁晋(E-mail:liangjin@mail.xjtu.edu.cn)依托单位:西安交通大学项目批准号:509752191.项目简介大型飞机模型在风洞试验时变形很大,需要精确测量其三维变形数据。本项目采用三维视频动态变形测量方法,在风洞试验时采用多组相机(两个相机为一组)高速拍摄模型多个部位的视频图像,计算飞机模型关键点各个时刻的三维坐标,从而计算出模型关键点的位移变化和变形数据。项目通过风洞现场试验和分析,获取风洞试验对测量精度的影响规律,建立测量误差模型。研究风洞变形测量的光束平差捆绑调整的模型和算法,实现多相机多时刻的三维变形测量,大大提高风洞试验的 相似文献
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飞机发动机零件的加工精度很高,而使用数控镗床和专用工装进行加工,则造成制造成本的浪费。讨论了孔系列组合夹具元件装配出的组合夹具在高精零件制造过程中的推广与应用,为飞机发动机公司降低生产准备成本探索出一条捷径。 相似文献
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基于国军标和适航标准对发动机冷却系统的验证要求,分析发动机短舱冷却系统在军机设计定型和民机适航取证试飞方面的不同,有助于我国军用航空发动机设计定型和大型民用发动机取证试飞水平的提升。 相似文献
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介绍了某飞机货舱固定式灭火系统验证试飞方法,重点论述了采样管改装方案、采样点布置方案、试验方案等方面的问题,为我国大中型运输机货舱灭火剂浓度测试积累了经验和试飞技术。 相似文献
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基于Fluent的MAF风洞标准实验模型研究 总被引:1,自引:0,他引:1
基于相似原理,设计适合于MAF风洞的弹丸模型,应用Fluent软件进行仿真模拟,得出的模拟数据与风洞实验数据进行对比,为制作实验模型累积标准实验数据,为开设风洞测试基础技术研究实验提供理论参考. 相似文献
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《Measurement》2016
Short duration wind tunnels offer an economical approach to study the aero-thermal operation of propulsion components, while reproducing temperature ratios, Reynolds and Mach numbers of the actual engine conditions. The present paper aims at modeling with high fidelity the von Karman Institute compression tube facility. This wind tunnel was simulated using the EcosimPro suite to characterize the behavior of each subcomponent during the whole test envelope, including the turbine map at off-design. The numerical predictions were then assessed through the comparison with experimental data. The model was proven to be an effective tool to accurately evaluate all the operating regimes that a research turbine experienced during the experimental sequence. Consequently, the present model allows exploiting the complete test run duration to obtain unique experimental data from the turbomachinery operating at far off-design conditions. The capability to experimentally test components at off-design is fundamental to understand the flow physics of any gas turbine engine operating at extreme conditions and to characterize the transient performances of fluid-machinery in high-speed propulsion concepts. However, technical dissemination on these aspects is scarce. 相似文献
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We analyzed the difference between FSI (fluid-structure interaction) analysis and a wind tunnel test regarding the uplift
force at each support point of a container crane and also design stowing devices — a tie-down rod and a stowage pin — and
an alarm system to prevent overturning of a container crane under wind loads. We know that FSI analysis agrees more with wind
tunnel tests than with structural analysis, but the results of FSI analysis are different from those of the tests. To evaluate
the effect of the wind load on the stability of the crane, two container cranes that are widely used in container terminals-50
ton-class and 61 ton-class container cranes-are adopted for the analytic model and 19 values are considered for the wind direction
as the design parameter. First, a wind tunnel test for the reduced-scale container crane model is performed according to the
wind direction using an Eiffel-type atmospheric boundary-layer wind tunnel. Next, FSI analysis for a full-scale container
crane is conducted using ANSYS and CFX. Then, the uplift force obtained from FSI analysis is compared with that yielded by
the wind tunnel test. Finally, a formula is suggested to compensate the difference between FSI analysis and the wind tunnel
test. 相似文献
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NF-3风洞螺旋桨动力实验的实时采集 总被引:1,自引:0,他引:1
主要介绍 NF— 3风洞螺旋桨段带动力实验中测控所用的主要部件 ,计算机实时采集系统 ,屏幕显示及编辑界面 ,主要技术指标和提高测试精度的措施。实时采集的数据与国外同类实验相比基本一致 ,表明得到的螺旋桨拉力系数 c T,功率系数 c P,效率η准确可靠。由于应用同步实时采集的方法 ,使测控系统测试精度有较大的提高 相似文献
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飞机在极端气候环境中飞行时,往往会引起飞机燃油系统结冰,使系统给发动机所供的燃油流量间歇中断或完全中断,从而导致飞行事故。因此,在当前新机研制中,对燃油系统的结冰问题加以重点考虑,并且不仅要在实验室对系统进行燃油结冰模拟试验,而且在型号试飞阶段也要模拟极端气候条件进行燃油系统结冰飞行试验,以便考核该条件下燃油系统供油能力和发动机工作可靠性。本文结合某型飞机燃油系统结冰试验技术攻关工作,研究飞机燃油系统结冰飞行试验的燃油配水方法和试验程序。 相似文献
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A low speed wind tunnel test was conducted for a canard airplane model in KARI LSWT. The purpose of the presented paper is to investigate the proper testing approach to correct tare precisely and the interference effects for the canard models which has 21% of canard-to-wing area ratio. Most of tests were performed with image system installation for various elevator deflection conditions at the fixed canard incidence angles. To evaluate the effectiveness of the image system, the obtained correction quantity at an zero elevator setting condition with image system was applied to the rest of elevator deflections and compared with the acquired results for all elevator deflections with image system. Test result showed that the amount of correction quantities were strongly dependent on the elevator deflections, and the difference in aerodynamic coefficients for two approaches was gradually amplified as the elevator deflection angles increased. An adoption of the image system was strongly recommended for the higher canard-to-wing area ratio model, if a proper level of accuracy was required. 相似文献