Finite-difference time-domain analysis on leak transmission characteristics of narrow gaps

The sound insulation performance of such wall systems as window sashes, doors, and movable partition walls is often affected by sound waves propagating through narrow gaps that exist at their peripheral parts. In this paper, the leak transmission characteristics through narrow gaps existing in the window sash was investigated through numerical and experimental studies. First, the validity of the finite-difference time-domain (FDTD) method with nonuniform-mesh system was confirmed through 1-dimensional and 2-dimensional numerical studies. Second, narrow gaps at the peripheral parts of a window sash were numerically modeled and their leak transmission characteristics were calculated by the 3-dimensional FDTD method. To evaluate the calculation results, they were compared with measurement results of leak transmission characteristics of a real window sash. As a result, numerical results showed good agreement with the experimental results.

[1]  Valtteri Hongisto,et al.  SOUND INSULATION OF DOORS—PART 1: PREDICTION MODELS FOR STRUCTURAL AND LEAK TRANSMISSION , 2000 .

[2]  Shinichi Sakamoto,et al.  Sound field simulation method by combining finite difference time domain calculation and multi-channel reproduction technique , 2004 .

[3]  Julian Schwinger,et al.  ON THE THEORY OF DIFFRACTION BY AN APERTURE IN AN INFINITE PLANE SCREEN. I. , 1948 .

[4]  Marion Burgess.  Resonator effects in window frames , 1985 .

[5]  E. T. Paris D.Sc.,et al.  L.On the coefficient of sound-absorption measured by the reverberation method , 1928 .

[6]  Walter W. Soroka,et al.  Approximation to the Diffraction of Sound by a Circular Aperture in a Rigid Wall of Finite Thickness , 1964 .

[7]  Jean-Pierre Berenger,et al.  A perfectly matched layer for the absorption of electromagnetic waves , 1994 .

[8]  Robert B. Newman,et al.  Collected Papers on Acoustics , 1927 .

[9]  Maeda Tadahiko,et al.  A Study on the Application Conditions of FDTD Subgridding Algorithm for the Analysis of Yagi-Uda Antennas Placed in the Vicinity of Building Structures , 2007 .

[10]  Jukka Keränen,et al.  Sound Insulation of DOORS—PART 2: Comparison Between Measurement Results and Predictions , 2000 .

[11]  Shinichi Sakamoto,et al.  Phase-error analysis of high-order finite difference time domain scheme and its influence on calculation results of impulse response in closed sound field , 2007 .

[12]  Takumi Asakura,et al.  Finite-Difference Time-Domain Analysis of Sound Insulation Performance of Wall Systems , 2009 .

[13]  P. T. Lewis.  Effect of frame construction on the sound insulation of unsealed windows , 1979 .