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Coupled rotor/fuselage dynamic analysis of the ah-1g helicopter and correlation with flight vibrations data
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Cronkhite, J. D. Sadler, S. G. Corrigan, J. C. Rogers, J. P. Dompka, R. V. Perry, K. S. |
| Copyright Year | 1989 |
| Description | Under a research program designated Design Analysis Methods for VIBrationS (DAMVIBS), existing analytical methods are used for calculating coupled rotor-fuselage vibrations of the AH-1G helicopter for correlation with flight test data from an AH-1G Operational Load Survey (OLS) test program. The analytical representation of the fuselage structure is based on a NASTRAN finite element model (FEM), which has been developed, extensively documented, and correlated with ground vibration test. One procedure that was used for predicting coupled rotor-fuselage vibrations using the advanced Rotorcraft Flight Simulation Program C81 and NASTRAN is summarized. Detailed descriptions of the analytical formulation of rotor dynamics equations, fuselage dynamic equations, coupling between the rotor and fuselage, and solutions to the total system of equations in C81 are included. Analytical predictions of hub shears for main rotor harmonics 2p, 4p, and 6p generated by C81 are used in conjunction with 2p OLS measured control loads and a 2p lateral tail rotor gearbox force, representing downwash impingement on the vertical fin, to excite the NASTRAN model. NASTRAN is then used to correlate with measured OLS flight test vibrations. Blade load comparisons predicted by C81 showed good agreement. In general, the fuselage vibration correlations show good agreement between anslysis and test in vibration response through 15 to 20 Hz. |
| File Size | 2849453 |
| Page Count | 154 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19890011141 |
| Archival Resource Key | ark:/13960/t4gn33p7h |
| Language | English |
| Publisher Date | 1989-01-01 |
| Access Restriction | Open |
| Subject Keyword | Structural Mechanics Dynamic Structural Analysis Flight Tests Interactional Aerodynamics Structural Vibration Rotor Aerodynamics Performance Prediction Ah-1g Helicopter Rotor Body Interactions Finite Element Method Airframes Coupled Modes Fuselages Nastran Vibration Tests 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 |
