文丘里曝气器布置对循环水体增氧效率的影响

Effects of Arrangement of Venturi Aerators on Aeration in Re-Circulating Water

为实现封闭循环水养殖系统中溶解氧的动态平衡,运用"对冲流动"理念与文丘里曝气器的自吸气增氧原理,设定15种工况,探究文丘里曝气器的对冲方式对水体增氧的影响.结果表明:氧体积传质系数与循环水体流量成正比;在同一流量条件下,氧体积传质系数与文丘里曝气器淹没深度成反比.结合增氧效果与对冲循环流场特性,建议在养殖初期与后期将文丘里曝气器安装为A—B层错层对冲,而在养殖中期调整为A—C层错层对冲.

In order to achieve dynamic balance in a re-circulating aquaculture system（ RAS）,the idea of＂opposing flow＂and the principle of Venturi air entrainment were adopted,and 15 experimental conditions were determined to investigate the effect of opposing flow on the aeration in water with different Venturi settings. The results show that the volumetric mass transfer coefficient of oxygen is proportional to water flow rate,but is inversely proportional to Venturi setting depth at the same flow rate. By comprehensively considering the aeration effect and the re-circulating opposing flow characteristics,it is suggested that Venturi aerator should be set as A—B stagger layer at the beginning and the end of cultivation,while it should be switched to A—C stagger layer in the mid-term cultivation.