Author(s)

Masumi Hasegawa^1*, Misaki Mori², Junji Matsumura¹

¹Department of Agro-Environmental Science, Faculty of Agriculture, Kyushu University, Fukuoka, Japan.
²Graduate School of Bioresource and Bioenvironmental Science, Kyushu University, Fukuoka, Japan.

The ultrasonic wave velocities of Japanese cedar columns were measured using a non-contact method. An air-coupled ultrasonic wave was propagated through the axial and lateral directions of wood. The velocities in the axial direction (V_L) showed the minimum values around the pith. The averaged V_L increased from 3600 m/s towards the outside of measurement area and attained the maximum values (=4010 m/s). The velocities in the lateral direction (V_RT ) showed no tendency among measurement points. The averaged V_RT was 1450 m/s. The velocities obtained using the non-contact method showed a significant positive relationship with those obtained using the contact method. The averaged ratio of V_L to V_RT was measured to be approximately 2.2 to 2.8. These ratios were in agreement with those from a contact method. These findings suggest that it is possible to measure the velocity in Japanese cedar columns with the non-contact method by using air-coupled ultrasonics.

Air-Coupled Ultrasonics, Velocity, Non-Contact Method, Nodestructive Evaluation, Japanese Cedar

Hasegawa, M. , Mori, M. and Matsumura, J. (2016) Non-Contact Velocity Measurement of Japanese Cedar Columns Using Air-Coupled Ultrasonics. World Journal of Engineering and Technology, 4, 45-50. doi: 10.4236/wjet.2016.41005.