The influence of steady-state thermal blooming effect on the quality of underwater laser power transmission

Aiming at the energy supply problem of underwater equipment such as manned deep submarines, submarine base stations, etc., this paper proposes an underwater high-energy laser wireless power transmission system and focuses on analyzing the influence of the steady-state thermal blooming effect on the quality of underwater high-energy laser power transmission. First, the intensity distributions under the influence of the thermal blooming effect are numerically simulated based on the multiple phase-screen method and the fast Fourier transform, considering the changes in the initial beam radius, transmission distance, transmitting power, wavelength, absorption coefficient of the water medium, and isobaric specific heat capacity. Emphatically, transmission efficiency and beam flux contrast are used to characterize the quality of power transmission and then find the suitable laser modes and seawater environment for underwater power transmission. The results indicate that reducing the thermal blooming effect may increase the efficiency of light energy transmission, but it will also decrease the photoelectric conversion efficiency of photovoltaic cells. Therefore, for balancing the energy transfer efficiency and the beam flux contrast, it is necessary to choose appropriate initial laser parameters based on actual underwater environmental parameters. Our study is helpful for the design of the underwater laser wireless power transmission system.