Dynamic characterization and resonances prediction of mechanical structures is a crucial issue in industry. Performing experimental modal analysis and harmonic response requires an excitation source able to operate in a wide frequency range, depending on the analyzed structure. In the present paper, the optimization and the design of an electromagnetic shaker is presented. This device has been engineered for a test bench to investigate the vibrational dynamics of centrifugal compressor bladed wheels. A really compact solution is needed since the final test bench provides up to 20 shakers on the circumference hoop, one for each blade, and the excitation frequency ranges from 1 to 10 kHz. Different stinger solutions are proposed and compared in the paper, in order to monitor the stinger effects on the dynamic response of the analyzed structure. The investigated solutions are: a beam stinger (diameter 1 mm), a wire stinger (diameter 0.2 mm), and a ball stinger (diameter 3 mm) which was tested with two different contact solutions. Experimental tests were performed on a shaker prototype to verify the vibrational loads applied by the device and to compare the different stinger solutions.
Design and optimization of a compact high-frequency electromagnetic shaker
BERTINI, LEONARDO;NERI, PAOLO;SANTUS, CIRO
2015-01-01
Abstract
Dynamic characterization and resonances prediction of mechanical structures is a crucial issue in industry. Performing experimental modal analysis and harmonic response requires an excitation source able to operate in a wide frequency range, depending on the analyzed structure. In the present paper, the optimization and the design of an electromagnetic shaker is presented. This device has been engineered for a test bench to investigate the vibrational dynamics of centrifugal compressor bladed wheels. A really compact solution is needed since the final test bench provides up to 20 shakers on the circumference hoop, one for each blade, and the excitation frequency ranges from 1 to 10 kHz. Different stinger solutions are proposed and compared in the paper, in order to monitor the stinger effects on the dynamic response of the analyzed structure. The investigated solutions are: a beam stinger (diameter 1 mm), a wire stinger (diameter 0.2 mm), and a ball stinger (diameter 3 mm) which was tested with two different contact solutions. Experimental tests were performed on a shaker prototype to verify the vibrational loads applied by the device and to compare the different stinger solutions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
