Frequency equation of axisymmetric guided waves in logs

Author

Huimin Yang ; Lihai Wang ; Li Li

Author_Institution

Key Lab. of Forest Sustainable Manage. & Environ. Microorganism Eng. of Heilongjiang Province, Northeast Forestry Univ., Harbin, China

Volume

4

fYear

2011

fDate

12-14 Aug. 2011

Firstpage

1964

Lastpage

1967

Abstract

According to the structure characteristics of logs, a log model with double layers (i.e. heartwood and sapwood) was constructed. Through the transmission characteristics of guided wave and the assumption of rigid connection at interface of heartwood and sapwood, the frequency equation of axisymmetric guided waves transmission in logs was deduced. In accordance with geometrical dispersion of guided wave in logs, Matlab was used to write the program, and the solution of frequency equation was gotten. Dispersion curve was calculated, the affect of different diameters to dispersion curve was analyzed, and the dispersion in decayed logs were compared to that in solid logs. This study provides the theoretical basis for guided wave using in internal decay detection of logs.

Keywords

frequency estimation; nondestructive testing; axisymmetric guided waves; double layers; frequency equation; geometrical dispersion; heartwood; internal decay detection; log model; sapwood; structure characteristics; transmission characteristics; Acoustics; Boundary conditions; Dispersion; Equations; Mathematical model; Stress; Testing; dispersion; frequency equation; guided wave; log;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic and Mechanical Engineering and Information Technology (EMEIT), 2011 International Conference on

Conference_Location

Harbin, Heilongjiang, China

Print_ISBN

978-1-61284-087-1

Type

conf

DOI

10.1109/EMEIT.2011.6023487

Filename

6023487