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Summary of the modeling and test correlations of a nastran finite element vibrations model for the ah-1g helicopter, task 1
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Berry, V. L. Cronkhite, J. D. Dompka, R. V. |
| Copyright Year | 1987 |
| Description | The AH-1G NASTRAN finite element model (FEM) is described and the correlations with measured data that were conducted to verify the model are summarized. Comparisons of the AH-1G NASTRAN FEM calculations with measured data include the following: (1) fuselage and tailboom static load deflection (stiffness) testing, (2) airframe ground vibration testing (0-30 H<), (3) airframe flight vibration testing (main rotor, 2,4, and 6/rev), and (4) tailboom effective skin static testing. A description of the modeling rationale and techniques used to develop the NASTRAN FEM is presented in conjunction with all previous correlation work. In general, the correlations show good agreement between analysis and test in stiffness and vibration response through 15 to 20 Hz. For higher frequencies (equal to or greater than 4/rev (21.6 Hz)), the vibration responses generally did not agree well. Also, the lateral (2/rev (10.8 Hz)) flight vibration responses were much lower in the FEM than test, indicating that there is a significant excitation source other than at the main rotor hub that is affecting the lateral vibrations, such as downwash impingement on the vertical tail. |
| File Size | 6436286 |
| Page Count | 303 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19870011940 |
| Archival Resource Key | ark:/13960/t4vj0f753 |
| Language | English |
| Publisher Date | 1987-01-01 |
| Access Restriction | Open |
| Subject Keyword | Structural Mechanics Finite Element Method Flight Tests Ground Tests Airframes Structural Vibration Mathematical Models Ah-1g Helicopter Nastran Aerodynamic Stability Aerodynamic Loads Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
