LMS Modal Analysis Techniques Dr Wei Chen LMS Shanghai Office LMS 模态分析模态分析 完整解决方案完整解决方案 2 LMS Modal Analysis Techniques 内容提要内容提要 2模态试验分析工具模态试验分析工具 1模态试验目的模态试验目的 3 模态仿真分析工具模态仿真分析工具 2 1 分析手段分析手段 2 2试验手段试验手段 2 3 数采前端数采前端 3 1 结构修改及预测结构修改及预测 3 2相关性分析相关性分析 3 3 预试验预试验 4 综述综述 3 LMS Modal Analysis Techniques X SourceReceiver Engine Rotor Road Gearbox MIMO Sine Multichannel FRF testing Multiple parallel measurement functions Fixed or user defined display layouts Clear measurement status indication Detailed overload information Level indicators The online shaker decorrelatio n check makes sure meaningful FRF results are measured For those cases were random fails Trimmed body modal testing Vibro acoustic modal testing Reciprocal noise transfer functions Dynamic mount stiffness identification Non linearity analysis The benefits of sine excitation in the measureme nt time of burst random 12 LMS Modal Analysis Techniques 模态试验方法模态试验方法 纯模态法纯模态法 Productive and flexible online monitoring gives confidence in the measured data Pre test function inspection Time Driving point FRFs coherences Force autopowers PCA shaker decorrelation check Multichannel FRF testing Multiple parallel measurement functions Fixed or user defined display layouts Clear measurement status indication Detailed overload information Level indicators 13 LMS Modal Analysis Techniques 模态试验方法模态试验方法 工作模态法工作模态法 Animating data directly after the measureme nt is a powerful data validation tool Dedicated processing of time data Exponential window for correct damping estimates hanning cannot be corrected Batch processing of multiple measurements Crosspower correlation function preview Operational modal analysis Determine dynamic properties in operation Resonant frequencies Damping values Mode shapes Multi run modal for increased mode shape quality and reliability 14 LMS Modal Analysis Techniques 内容提要内容提要 2模态试验分析工具模态试验分析工具 1模态试验目的模态试验目的 3 模态仿真分析工具模态仿真分析工具 2 1 分析手段分析手段 2 2试验手段试验手段 2 3 数采前端数采前端 3 1 结构修改及预测结构修改及预测 3 2相关性分析相关性分析 3 3 预试验预试验 4 综述综述 15 LMS Modal Analysis Techniques 模态分析工具模态分析工具 LSCE法法 Automatic scrolling FRF synthesis reduces the time to validate the modal model Operator guidance makes modal analysis faster and easier then ever before Fast and easy modal parameter estimation Only 3 steps to get to mode shapes Improved industry standard LSCE Built for large datasets Full traceability back to used transducer Extensive modal validation tools Geometry based FRF synthesis Automatic scrolling FRF synthesis Mode Correlation Complexity Automatic visual comparison of 2 modes Animation Color displays Rule based method Not affected by ability of human mind to treat information High accuracy on pole selection Reduce uncertainty 16 LMS Modal Analysis Techniques 模态分析工具模态分析工具 PolyMax法法 LMS PolyMAX results in crystal clear stabilization diagrams leading to user independent high quality modes On complex data traditional techniques often result in difficult to interpret stabilization diagrams Extremely clear stabilization Fast Easy pole selection User independent results More higher quality modes General purpose method Single broadband analysis High low damping Noisy data Built for large complex structures Trimmed body powertrain assembly Aircraft spacecraft Turbomachinery civil structures PolyMAX AMPS generate automatically user independent results 17 LMS Modal Analysis Techniques 工作模态分析工具工作模态分析工具 BR法法 Extremely clear stabilization Fast Easy pole selection User independent results More higher quality modes General purpose method Single broadband analysis High low damping Noisy data Built for large complex structures Trimmed body powertrain assembly Aircraft spacecraft Turbomachinery civil structures Operational deflection shapes provides insights in vibration and acoustic problems Batch processing of multiple measurement is fast and easy 18 LMS Modal Analysis Techniques 一步到位的参数提取工具一步到位的参数提取工具 Automatic data retrieval Analysis data sets build and expand while the measurements proceed no manual index table Clear overview of all FRFs in one table Multi run modal analysis Compensation of frequency shifts between runs due to mass loading or temperature effects Automatic merging of modes from different runs Consistent less complex mode shapes Multi run modal results in higher quality mode shapes making inconsistent data consistent 1st Mode Shape 467 Hz 8 6 4 2 0 2 4 6 8 8 6 4 20246810 Real Im a g in a ry Merged All runs All measured functions at a glance in a single table ready to analyze AMPS rule based method Not affected by ability of human mind to treat information High accuracy on pole selection Reduce uncertainty All physical poles selected at a glance in stabilization diagram 19 LMS Modal Analysis Techniques LMS Test Lab modification prediction Efficient troubleshooting let the tool do the repetitive work faster and more consistent tuned absorbers provide a shortcut solution to solve a probem in a late product design stage Evaluate structural design changes without repeated