水产学报2023，Vol.47Issue(12)：190-201,12.DOI:10.11964/jfc.20220513484
水下集鱼灯在近海水体中的光场分布数值模拟
Numerical simulation on illumination distribution of underwater fishing lamp in offshore marine water
摘要
Abstract
The illumination distribution in water is an important subject for efficient application research of fish-ing lamp.The traditional numerical calculation method could not accurately calculate the illumination distribution of the underwater fish gathering lamp in the offshore water.A new computing model of underwater illumination of fishing lamp was developed based on Monte Carlo method by using spectrum and luminous intensity of lamps and the inherent optical properties of seawater.Firstly,the vertical marine section was set as the target surface and divided it to some grids;secondly,photons with specific wavelength and direction were generated by random num-ber method,and then the attenuation coefficient of each photon was calculated by using chlorophyll concentration data,optical characteristics of pure seawater and its relationship with absorption and scattering coefficients;finally,all photons were emitted,and their transmission paths were tracked.The photons were recorded only if they fell into the target surface and the illuminance value of each grid was calculated according to the recorded position of photons.The calculation method was verified with flume test through collecting water samples.The Ads—area of closed region which enclosed by 0.1 lx contour line in marine section which ds m away from underwater fish-ing lamp and the Ids—maximum illuminance value in marine section were used to characterize the spatial dis-tribution of light field in water.In this paper,the effect of chlorophyll concentrations,scattering type in the marine water and the scattering asymmetry parameters on the illumination distribution of LED fishing lamp and MH fishing lamp were analyzed through numerical simulation.The results showed:(1)with the chloro-phyll concentration increases from 1 mg/m3 to 5 mg/m3,the A5m of LED lamp decreased from 1 073.90 m2 to 292.87 m2,which means A5m has reduced by 72.73%;the A5m of MH lamp decreased from 1 094.51 m2 to 304.57 m2,which means A5m has reduced by 72.17%;the I5m of MH decreased from 972.76 lx to 454.42 lx,which means the I5m has reduced by 53.29%;the I5m of LED decreased from 956.48 lx to 318.60 lx,which means the I5m has reduced by 66.69%.(2)when scattering type of the ocean water is Mie scattering and Rayleigh scattering,the I5m of MH is 956.48 lx and 318.60 lx,respectively;the I5m of LED is 1 057.96 lx and 992.42 lx,respectively.(3)with the scattering asymmetry parameters increases from 0.80 to 0.99,the A5m of MH lamp decreased from 1 094.89 m2 to 1 336.40 m2,A5m increased 22.05%;the A5m of LED lamp decreased from 1 076.52 m2 to 1 325.21 m2,A5m increased 23.10%;the I5m of MH increased from 962.52 lx to 1 122.48 lx,I5m increased 16.62%;the I5m of LED increased from 980.74 lx to 1 123.22 lx,I5m increased 14.53%.It was found chlorophyll concentrations had a significant effect on illumination distribution of fishing lamp,while the scattering type and the scattering asymmetry paramet-ers on the illumination distribution had no significant effects.The numerical simulation method proposed in this paper can accurately calculate the illumination distribution of fishing lamps in offshore waters,which would provide scientific basis for fishery supervision and reasonable application of fishing lamps.关键词
水下集鱼灯/光场分布/数值模拟/近海水体/叶绿素a质量浓度Key words
underwater fishing lamp/illumination distribution/numerical simulation/offshore marine water/chlorophyll-a concentration分类
农业科技引用本文复制引用
王伟杰,万荣,孔祥洪..水下集鱼灯在近海水体中的光场分布数值模拟[J].水产学报,2023,47(12):190-201,12.基金项目
国家重点研发计划(2020YFD0901203) National Key Research and Development Program(2020YFD0901203) （2020YFD0901203）
