• DOI:10.1063/1.4985159
• Corpus ID: 119478399

Electronically steerable ultrasound-driven long narrow air stream

@article{Hasegawa2017ElectronicallySU,
  title={Electronically steerable ultrasound-driven long narrow air stream},
  author={Keisuke Hasegawa and Liwei Qiu and Akihito Noda and Seki Inoue and Hiroyuki Shinoda},
  journal={Applied Physics Letters},
  year={2017},
  volume={111},
  pages={064104}
}

• K. Hasegawa, Liwei Qiu, +2 authors H. Shinoda
• Published 3 April 2017
• Physics
• Applied Physics Letters

Acoustic streaming, which is the unidirectional movement of a medium driven by its internal intense acoustic vibrations, has been known for more than a century. Despite the long history of research, there have been no scientific reports on the creation of long stretching steerable airflows in an open space, generated by ultrasound. Here, we demonstrated the creation of a narrow, straight flow in air to a distance of 400 mm from an ultrasound phased array emitting a Bessel beam. We also demonstrated that the direction of the flow could be controlled by appropriately tuning the wavefronts of the emission from the phased array. Unlike conventional airflows such as those generated by jets or fans, which decelerate and spread out as they travel farther, the flow that we created proceeded while being accelerated by the kinetic energy supplied from the ultrasound beam and keeping the diameter as small as the wavelength. A flow of 3 m/s with a 10 mm diameter extended for several hundreds of millimeters in a room ...