Analysis of influence of acoustic wave disturbance on internal and external scale and refractive index power spectrum function of atmospheric turbulence

Abstract

Sound wave is a kind of mechanical wave, and as the carrier of energy, its transmission in the atmospheric turbulence environment will “disturb” the change of turbulence dissipation rate, thus affecting the evolution of turbulence physical structure. Using the acoustic energy and turbulent energy balance equations and combining the inner and outer scales of turbulence and the atmospheric refractive index power spectral function, this work studies the variation characteristics of the inner and outer scales and refractive index power spectral functions of atmospheric turbulence under different acoustic disturbances. The results show that the propagation of different acoustic waves can cause the internal and external scales of turbulence to change. The greater the sound source power, the stronger the influence on the scale of turbulence is. However, the greater the sound source frequency, the less significant the influence on the scale of turbulence is. The propagation of different sound waves can change the atmospheric refractive index power spectrum function. In the inertial region, considering the effects of sound waves on the inner and outer scales of turbulence, the influences of different sound sources on the atmospheric refractive index power spectrum are different. In a dissipative region, the atmospheric refractive index power spectrum fluctuates with the transmission distance of sound wave. This work explores the acoustic-wave caused variation of the characteristic parameters of the refractive index power spectrum function of atmospheric turbulence, providing a theoretical basis for studying the laser propagation characteristics and acoustooptic coupling in atmospheric turbulence caused by acoustic waves.