When the finite element model of a complex structure is partitioned into substructures in order to enable component mode synthesis, the reduced order model obtained from the Craig-Bampton method often features a large number of interface degrees of freedom (DOF). The authors have recently developed a method to reduce the interface DOF by using a set of so-called characteristic constraint (CC) modes. The resultant, highly compact CC-mode-based reduced order model provides a good platform to calculate the power flow between substructures. In this paper, the CC-mode method is applied to the finite element model of a vehicle structure with about 1.5 million DOF. A convergence study is conducted to find optimal mode selection criteria, and a 2124 DOF reduced order model is obtained for the 0-200 Hz range by using the CC-mode method. Then, a forced response analysis is carried out to verify its accuracy for capturing dynamic response, and a power flow analysis is carried out to demonstrate its capability for identifying critical power flow paths. A novel presentation method is adopted to display power flow through the vehicle structure as a two-dimensional “map”. From the power flow maps, the structural paths through which the vibration energy is transmitted from the source to the key response points are clearly illustrated.
Vibration and Power Flow Analysis of a Vehicle Structure Using Characteristic Constraint Modes
Sae Technical Papers
SAE 2003 Noise & Vibration Conference and Exhibition ; 2003
2003-05-05
Aufsatz (Konferenz)
Englisch
Vibration and power flow analysis of a vehicle structure using characteristic constraint modes
Kraftfahrwesen | 2003
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