The formula of the vibration response and power flow in beam-stiffened plate with force excitation applied on.the plate, have been obtained by using the Steepest Descent Integral method. The characteristics of the pow...The formula of the vibration response and power flow in beam-stiffened plate with force excitation applied on.the plate, have been obtained by using the Steepest Descent Integral method. The characteristics of the power flow have been studied through computer simulation.It is shown that the stiffener acts as an extra lineal excitation applied on the plate and changes the characteristics of the power flow of the infinite plate greatly The greater the stiffness and the smaller the distance between the exciting point and the stiffener is, the greater the induence is. Lastly, experiments have been carried out by using the dualaccelerometer measurement technique that based on cross spectrum, and the test data agree well with the theoretical results展开更多
The vibration and sound radiation of a submerged spherical shell are studied in the time-domain by Laplace transform method, where a CW pulse force acts at the apex of the shell. The numerical results for the case of ...The vibration and sound radiation of a submerged spherical shell are studied in the time-domain by Laplace transform method, where a CW pulse force acts at the apex of the shell. The numerical results for the case of long pulse show that the different vibrational modes and the resonant or beat radiated sound are excited for different carrier-frequencies, but litle sound is radiated for some vibrational modes. For the case of short pulse the waveforms of the pulse become widened and deformed, when the pulse propagates between apexes of the shell. Then, the Doubly Asymptotic Approximations (DAA2) and Kirchhoff's Retarded Potential Formulate (KRPF)are used to solve the same problem. It is shown that the results of DAA2 and KRPF method have a good agreement with the results of Laplace transform method.展开更多
文摘The formula of the vibration response and power flow in beam-stiffened plate with force excitation applied on.the plate, have been obtained by using the Steepest Descent Integral method. The characteristics of the power flow have been studied through computer simulation.It is shown that the stiffener acts as an extra lineal excitation applied on the plate and changes the characteristics of the power flow of the infinite plate greatly The greater the stiffness and the smaller the distance between the exciting point and the stiffener is, the greater the induence is. Lastly, experiments have been carried out by using the dualaccelerometer measurement technique that based on cross spectrum, and the test data agree well with the theoretical results
文摘The vibration and sound radiation of a submerged spherical shell are studied in the time-domain by Laplace transform method, where a CW pulse force acts at the apex of the shell. The numerical results for the case of long pulse show that the different vibrational modes and the resonant or beat radiated sound are excited for different carrier-frequencies, but litle sound is radiated for some vibrational modes. For the case of short pulse the waveforms of the pulse become widened and deformed, when the pulse propagates between apexes of the shell. Then, the Doubly Asymptotic Approximations (DAA2) and Kirchhoff's Retarded Potential Formulate (KRPF)are used to solve the same problem. It is shown that the results of DAA2 and KRPF method have a good agreement with the results of Laplace transform method.
