Abstract：In order to study the influence of the number of blades on the aeration performance of inverted umbrella aerator under various flow conditions, two impellers respectively with 6 blades and 8 blades were fabricated for an inverted umbrella aerator. Then, dissolved oxygen experiments were carried out to study the aeration performance of the aerator. The total oxygen transfer coefficient, standard oxygenation capacity and standard dynamic efficiency were measured at two numbers of blades by changing liquid level height in the aeration tank and immersed depth of the aerator. At the same rotative speed, the 8-blade aerator is subject to significantly higher standard oxygen total transfer coefficient and standard oxygenation capacity than the 6-blade aerator. When the number of blades increases, the impellers have a stronger throwing and sprinkling strength, but also the contact area between the liquid and the air is expanded, thus a greatly improving efficiency of oxygen mass transfer is resulted. Additionally, the fluctuation of the liquid near the free surface is intensified, the interaction between the liquid and the bubbles becomes stronger, thus the turbulent mass transfer is enhanced. However, the increase in the number of blades will consume more power, consequently, the standard power efficiency of two aerators with two numbers of blades shows a little difference at an identical rotative speed. Nevertheless, the study provides a certain reference for the economical operation of an inverted-umbrella aerator.
刘厚林,尚欢欢,唐晓晨,张兴,董亮*,郭瑾楠,汪文生. 叶片数对倒伞曝气机曝气性能影响试验研究[J]. 排灌机械工程学报, 2020, 38(9): 922-927.
LIU Houlin,SHANG Huanhuan,TANG Xiaochen,ZHANG Xing,DONG Liang*,GUO Jinnan,WANG Wensheng. Experiment on influences of number of blades on aeration performance of inverted-umbrella aerator. Journal of Drainage and Irrigation Machinery Engin, 2020, 38(9): 922-927.
