Response of a thin‐walled pipe section due to external excitation using energy accountancy II: Experimental study

Abstract

The response of a thin‐walled pipe section excited by an external force can be obtained using the energy accountancy method as described in the first part of this series of two papers. In order to verify this approach, an experimental study was conducted on a 2.88‐m‐long, thin‐walled steel pipe section containing two different fluids, air and water. The pipe section, 0.06 m in diameter and 0.003 m thick, was simply suspended by wires with no other outside connections. The pipe was excited externally by a calibrated hammer with the response of the pipe measured by an accelerometer attached to the outer surface of the pipe. In these experiments the internal fluid was stationary. This did not impose any limitations on the understanding obtained from the experiments since, for water systems, the flow is at a very low Mach number and therefore the effects of the flow are negligible. The results obtained show good agreement between the measured energy input and the measured dissipated and radiated energy components, the energy levels being within 1 dB of each other. This verified the application of the energy accountancy concept in describing the response of a thin‐walled pipe section. Furthermore, the results obtained can be simplified into a diagnostic tool which can be used for noise control purposes.