TY - BOOK
T1 - Determination of radiated sound power by acoustic intensity measurement using Fourier analysis
AU - Lahti, Tapio
PY - 1982
Y1 - 1982
N2 - A review is given on the theory, applications,
measurement techniques and estimation errors of the
direct determination of acoustic intensity. Problems
encountered with the calibration of equipment and the
recording of intensity signals in the field are
discussed. A practical system for measuring intensity is
described which consists of two microphones, a tape
recorder and a dual channel FFT analyzer. The system was
calibrated using a new method involving electrostatic
actuators. Correct operation of the system was verified
in two test measurements, inside a standing wave tube and
in a reverberation room. An extension to the
two-microphone cross-spectral method of determining
intensity is suggested to yield directly the specific
acoustic impedance by the aid of two pressure microphones
and the FFT processing of the two signals. Further, the
impedance can be utilized in the direct determination of
the radiation and absorption coefficients.
AB - A review is given on the theory, applications,
measurement techniques and estimation errors of the
direct determination of acoustic intensity. Problems
encountered with the calibration of equipment and the
recording of intensity signals in the field are
discussed. A practical system for measuring intensity is
described which consists of two microphones, a tape
recorder and a dual channel FFT analyzer. The system was
calibrated using a new method involving electrostatic
actuators. Correct operation of the system was verified
in two test measurements, inside a standing wave tube and
in a reverberation room. An extension to the
two-microphone cross-spectral method of determining
intensity is suggested to yield directly the specific
acoustic impedance by the aid of two pressure microphones
and the FFT processing of the two signals. Further, the
impedance can be utilized in the direct determination of
the radiation and absorption coefficients.
M3 - Report
SN - 951-38-1480-7
T3 - Valtion teknillinen tutkimuskeskus. Tutkimuksia - Research Reports
BT - Determination of radiated sound power by acoustic intensity measurement using Fourier analysis
PB - VTT Technical Research Centre of Finland
CY - Espoo
ER -