nCode 疲劳耐久性工程
高级培训班
整车/零部件台架耐久性试验
及其试验加速技术零部件台架模拟试验
是一体化解决疲劳问题的策
略中的重要一环！
微波炉
鼓励读书的唯美句子重新设计优化
重新设计优化零部件模拟试验零部件模拟试验计算机辅助
疲劳寿命模拟计算机辅助
疲劳寿命模拟用户使用情况用户使用情况实测载荷实测载荷应力分析应力分析材料性能材料性能产品寿命
产品寿命
关联产品寿命
产品寿命加速的
Sign-off 试验加速的Sign-off 试验
台架试验的好处
•可重复的试验环境
•易对试验进行监控
•通过比较试验对设计
参数变化进行评价
•早期检验零部件的性能
•可能能实现试验加速
•验证理论模型•...
根据实测的载荷及响应信号，在实验室里
重现实际工况，模拟零部件的性能及寿命
进行台架试验的好处：
台架试验时也可进行数据采集！
做哪些台架试验？
•能模拟道路试验的台架试验案场客服
•能一定程度评价零部件耐久性能的试验•模拟损伤最严重的，要看车辆的特点•。。。
不要做和实际工况无关的试验！
实验室负责人的困境
•预先预测台架试验大概需要多长时间，费用大概多少？•高效地利用试验台
•判断被要求做的试验是否是一个不合理的试验
•在试验开始前，使用疲劳编辑技术“合法地”加速试验•“合法地”过滤掉试验台不能模拟的高频
•…
要求的疲劳寿命要长，
但试验结果必须尽快出来!
疲劳分析能够帮助...
How should we test in lab?
From P.G. or Field to Test Rig
Customer Usage Test Track
Individual
Surfaces, Events
Test Rig
What Do We Want From A Durability Test?•Durability test that ’s suitable for the item in question: a component, sub-asmbly, or a whole vehicle疫情的感想
•Test must replicate the same failure
mechanisms as en in the real world
•Test should be reprentative of the real
loading environment
•Test should be accelerated where possible to reduce project time scales and costs
•Test specification can be ud in FE bad virtual test or real physical test
Test Synthesis –Route Map葫芦龙头缠线图
Deterministic
天吧
Random Quasi-static Dynamic Uniaxial Multiaxial Test Synthesis Frequency Domain
Time Domain
Peak-Valley Domain
Dynamic Time Series Load Scaling Uniaxial Signal / Fatigue Fatigue Editing Accelerated Testing •PSD random •Sine sweep •Sine on random •Peak valley extraction
•Block load quence
she中国话
•Statistical exceedence
•Constant amplitude
诱捕黄鳝•Is it dominant plane?
•Multiaxial peak valley
extraction •Buffered fatigue editing •Remote parameter simulation test •Proving ground •Increa frequency of Time Series
Vibration Load Scaling Deterministic and Stochastic
Deterministic Stochastic
Load Scaling
Load Scaling
•Scaling up the load will reduce the test duration exponentially.•Target life is influenced by endurance limit and ont of local plasticity as well as dynamic respon of component
•Scaling should be ud with extreme care to avoid local yielding and changing the load paths
•Not suitable for most inertia reacted tests
Scaled Range
Original Range
Real Duration
Test Duration
Where b is the Basquin Exponent (gradient of SN curve)
This is only approximate!Load Scaling
Positive •Maintains Sequence •Maintains Pha between multiple channels •Maintains Frequency
Content
Negative
•Amplitude is not maintained (may affect the failure mechanism)Increasing Load Frequency
