Abstract：In order to investigate the impact of fluid velocity on the acoustic field of finite-length duct, the cut-off frequency is deduced based on the acoustic modal theory. Then, the interior and exterior acoustic field of finite-length duct is calculated on conditions of varied fluid velocities, duct radiuses and radius-to-wavelength ratios. It is shown that for the identical duct and sound source, the cut-off frequency decreases when fluid velocity increases. Besides, sound energy at the side wall and downstream nozzle of the duct moves upwards due to the presence of fluid velocity, which is more obvious at low frequency or large fluid velocity.
吕晓军;杨迎春;周其斗. 介质速度对有限长导管内外声场影响研究[J]. , 2013, 32(11): 145-148.
LV Xiao-jun;YANG Ying-chun;ZHOU Qi-dou. Effect of fluid velocity on the acoustic field of a finite-length duct. , 2013, 32(11): 145-148.
2013, Vol. 32 
