vibration_isolation_material_introduction 振动.ppt

 Vibration Shock Isolation Material Introduction Vibration Isolation Theory Resonance Example * 2nd Run 1st Run SDOF (P800) Aout-- Ain-- M K C FD = The frequency of the input force FN = Natural frequency of the system = 1/2π √(K/M) (P800) Peak become higher and sharper ? Damper has lower damping Peak shift to lower frequency ? Damper has lower stiffness (softer) Shock Isolation Theory SDOF t : duration of pulse fstruct = nature frequency of (rigid body + isolator) Rc = Damping value Gin = Input G level Gout = Output G level Dynamic Mechanical Analyzer , DMA Perkin Elmer Model : DMA 7 Series DMA can be simply described as applying an oscillating force/temperature to a sample and analyzing the material’s response to that force. tanδ= E’’/ E’ E’ : store energy E’’ : loss energy tanδ vs. Temperature - Example PMP P800 C-1002 tanδ vs. Frequency - Example PMP P800 C-1002 Modulus vs. Temperature - Example Modulus vs. Frequency - Example *