LED水下集鱼灯光场分布数值模拟分析

Numerical simulation analysis on light field distribution of LED underwater fishing lamp

为探究LED水下集鱼灯光色、功率、放置深度和海水叶绿素质量浓度对光场分布的影响,基于蒙特卡罗模拟方法建立了水下光束传输数值计算模型,通过控制变量法计算了不同条件下的水下光场分布,并提出以0.1~10.0 lx等值线所包围的面积与计算截面面积比值为相对有效光照范围(relative effective illumination range,REIR)。以REIR为评价指标,对不同条件下的光场分布进行了分析。结果显示:(1)相同功率条件下,REIR依次为绿光>白光>蓝光,以功率420W、叶绿素质量浓度0.1mg/m^(3)为例,3种光色的REIR比值为1.58∶1.31∶1;(2)相同光色条件下,当叶绿素质量浓度为0.1mg/m^(3)时,集鱼灯功率由420W增至1200W,蓝、绿、白3种集鱼灯的REIR分别由31.68%、50.27%、41.78%增至38.59%、56.91%、50.15%,功率增加近3倍,但REIR增幅有限;(3)随着集鱼灯放置深度增加,REIR先增加后稳定;以叶绿素质量浓度1.0mg/m^(3)、功率为420W为例,绿光集鱼灯与白光集鱼灯REIR的最大值约为9.69%~9.84%,出现在放置水深20m左右;而蓝光集鱼灯的REIR最大值约为5.60%,出现在放置水深15m左右;(4)当集鱼灯功率为420W,海水叶绿素质量浓度从0.1mg/m^(3)增至5.0mg/m^(3),蓝、绿、白3种光色集鱼灯的REIR分别由31.89%、48.25%、42.05%减少至1.65%、2.09%、2.22%。研究结果可为LED水下集鱼灯光色功率选型、深度放置以及有效光场分布范围估算提供参考。

To investigate the effects of light color,power,depth of LED underwater fishing lamp and seawater chlorophyll concentration on its light field distribution,a new underwater light transmission model was established based on Monte Carlo algorithm.The underwater light field distribution under different conditions was calculated by using the control variable method and the relative effective illumination range(REIR).The ratio of the area surrounded by the 0.1-10.0 lx isoline to the computational domain was taken as an evaluation index.With REIR for index,light filed distribution under the combined condition of was analyzed.The results showed that:(1)Under the same light power,the lights with REIR from high to low were green light,white light and blue light,and when the light power was 420 W and the seawater chlorophyll concentration was 0.1 mg/m^(3),the ratio of REIR values of the three light colors was 1.58∶1.31∶1;(2)Under the same light color,when the seawater chlorophyll concentration was 0.1 mg/m^(3),the power of fishing lamp increased from 420 W to 1200 W,and the REIR value of blue,green,and white light lamp increased from 31.68%,50.27%and 41.78%to 38.59%,56.91%and 50.15%respectively;while the power of lamps increased nearly three times,the increase of REIR was limited;(3)As the depth of lamp increased,the REIR of lamps increased at first and then kept stable.The maximum value of green and white lamp was about 9.69%-9.84%when the depth of lamp reached 20 m under water,while the maximum value of blue lamp was about 5.60%when the depth of lamp reached 15 m under water;(4)As the chlorophyll concentration increased from 0.1 mg/m^(3)to 5.0 mg/m^(3),the REIR value of green,white and blue lamp decreased from 31.89%,48.25%and 42.05%to 1.65%,2.09%and 2.22%respectively.The results can be helpful for the selection of light color and power,the depth of underwater lamp,and the estimation of effective illumination range of lamp.