Power Injection Method-based evaluation of the effect of binding technique on the Coupling Loss Factors and Damping Loss Factors in Statistical Energy Anal-ysis simulations

Abstract

Measurement results on the Damping Loss Factor (DLF) and Coupling Loss Factor (CLF) between two steel plates is presented for 19 different junction types. The junctions involve joining technologies, such as line welding, point welding, bolting, riveting, gluing or their combinations, and with varying spacing between the junction points and the angle between the plates. From the measurement results, the DLF and CLF values were calculated by the Power Injection Method for the purposes of being applied in Statistical Energy Analysis simulations. Four excitations were applied at each subsystem by impact hammer, while the response was recorded at sixteen response points at each subsystem. The measured CLF values were compared to each other from various aspects. Data were compared to the results obtained from SEA simulations by using the built-in analytical formulas. In general, good comparison was observed, although the results appeared to be somewhat dependent on the frequency band. Finally, it was examined whether replacing the DLF values with data obtained for an uncoupled flat plate, as well replacing the CLF values with data from analytical formulas leads to acceptable accuracy of the simulation results.

Validation of finite element connection modeling by comparison of experimental and virtual power injection methods

“…Some of the most common connection types were investigated in this study, based on the work of Treszkai et al [10] The first model was a single piece of sheet metal bent in 90° with 2 mm nominal thickness. The junction created by the bending split the structure into 2 subsystems.…”

“…The dimensions of the plates are approximately 650×550 mm, but due to the connection to be realized, there is a 20 mm overlapping area between the plates. This overlap for the connection was always formed from Plate 1 and bent in 90°, as described in [10]. The finite element model of the bent variant is shown in Fig.…”

“…This time, a single HEXA element was created in the connection and similarly to the line welded variant, the material properties of the solid elements were set to steel. The measurement process that provided the data for this comparison is described more in detail in [10]. In short, impact testing methodology was employed with a total of 12 accelerometers per plates in 4 runs.…”

“…Several papers deal with the analytical and experimental determination of CLFs and DLFs for coupled plates. Treszkai et al [10] investigated 19 different joining methods and compared experimental results to analytical SEA results. Panuszka et al [11] investigated L-shaped structures with different joint types and thickness ratios.…”

“…To do so, the least possible complex test cases were assembled, also described in the next chapters. The experimental data was provided by former measurements, carried out in the work of Treszkai et al [10]. The finite element modeling method of each connection type can be also validated through this comparison.…”