声疲劳仿真计算实例-virtual.lab版

声疲劳仿真计算实例 Acoustic fatigue By Li Zenggang Mobile: Email: forengineer@126.com Step 1 Import the structure and acoustics meshes  Start->Acoustics->Acoustic Harmonic BEM  File->Import. First select nastran input file structure.bdf file, the units are MKS.  File->Import. First select nastran input file acoustics.bdf file, the units are MKS.  File->Import. First select nastran result file fine_mesh.op2 file, the units are MKS. Please check on the mesh and mode set. Step 2 Define the mesh part type  Tools-> Set mesh parts type Step 3 Solve the number conflicts  Tools->Nodes and Elements ID -> Renumber Nodes and Elements Id. First select the structure mesh and renumber the mesh from 10000. Second select the acoustics mesh and renumber the mesh from 20000.  Tools->Nodes and Elements ID ->Check ID Conficts. Press check button and you can find there are no conflicts. Step 4 Carry out the acoustic preprocessing  Insert->Acoustic mesh preprocessing set. Double click the Grid Support in the tree and the select the acoustic mesh. Right click on the Acoustic Mesh Preprocessing Set and select Update. Step 5 Define the material and property  Insert-> Materials->New Materials ->New fluid Material. Accept the default value. Change the Name to air.  Insert ->Properties->New Properties -> New acoustic fluid property. Select the acoustic mesh and the fluid material from tree. Step 6 Transfer the modes  Insert -> Other analysis cases -> Data Transfer analysis case. Select the Mode Set.1 from tree.  Double click the Source Set and the select the fine_mesh from the tree. Double click the Target Set and select the structure mesh. Double click the Mapping Data and input 4 for the Number of Nodes and 6mm for the Maximm Distance. Click the Compute and OK button.  Right click the Data Transfer Solution Set and select Update. Step 7 Define the random diffuse field  Insert -> Functions Creator-> Random Crosspower Set. Double click on the Reference Autospectra, from the values lab press , and then import the data from Pressure_PSD.xls file.  Double the Reference Points and select the Insert Multiple Nodes and reference the STRUCTURE MESH AND SET THE DOF TO S. Step 8 De-composite the random case into un-correlated cases  Insert -> Other Analysis Cases ->Principle Component Analysis. Reference the existing Crosspower set: Random Crosspower Set  Double click the PCA Vector Case in the tree and then set the frequency range and Tunction Conditions as follows:  Right click on the PCA Vector Case and select Update. Step 9 Carry out the Vibro-Acoustic Analysis  Insert -> BEM Analysis Cases -> Vibro-Acoustic Response Analysis Case with Surrogate Mesh  Double click on the Location of the Wetted Surface in the tree and then select the structural mesh or acoustic mesh.  Double click Vibro-Acoustic Response Solution Set with Surrogate Mesh and then set the frequency range from 10Hz to 100Hz linstep 1Hz.  Right click on the Vibro-Acoustic Response Solution Set with Surrogate Mesh and select Update or Compute. Step 10 Carry out the Modal-Based Random Post-Processing Case  Insert->Other Analysis Cases->Modal-Based Random Post-Processing Case. Please select the Mode Set.1( Of fine mesh) , Modal Participation factors of Vibro-acoustics case and the Virtual Autopowers of PCA case  Hide all the mesh parts except the fine mesh. Double click the Output Set and change the Physical Data Type to Acceleration Cross Power. Double click on the Multiple Node IOPoint and then select several nodes of Fine Mesh.  Double click on the Modal-based Random Response Solution Set, and set the results as Functions and save the auto and cross powers. Step 11 Carry out the Finite Life Durability Cases  Start -> Durability-> Durability Analysis  Insert -> Finite Life Durability Cases -> Stress Life Analysis Case. Select Modal-Based Random Post-Processing Case from the tree. Set the Duration of Load Application to 10000 s. Set the task definition to fine mesh.  Double click on the SN Curve and select the Sample Steel.  Double click the Fatigue Parameter, and set the Database to Vibration Fatigue and select Dirlik, Critical plane, open mode (I), Goodman correction / Vibration Fatigue  Right click on the Durability Stress Life Analysis Solution and select Update or Compute.  Generate an Image of Fatigue Damage on the Durability Stress Life Analysis Solution 北京诺斯多维科技有限公司简介 诺思多维是一家专门从事CAE工程咨询和软件代理的公司，以振动噪音为主，涉及的学科包 括声学计算、振动计算、疲劳计算、多体动力学计算、有限元建模和计算（线性和非线 性）、流体CFD计算、电磁场计算、焊接仿真计算、碰撞冲击爆炸计算、转子动力学计算、 液压传递和控制、相关性和修正计算以及多学科优化等；同时诺思多维也代理以上仿真产 品的CAE软件以及CAD设计软件。诺思多维有来自各行业的的专业技术团队，能给用户最 好的技术支持和培训，保证能用户能把软件用户。如有项目合作、软件采购(如 sysnoise和virtual.lab等）和培训，请通过邮件forengineer@126.com与公司负责人李增刚 （qq:56873276)联系。