导流罩对推流器性能的影响研究

Research on the Influence of the Deflector on the Performance of Thruster

在污水的处理过程之中,潜水搅拌器作为污水处理的主要核心部件之一,它的工作性能和作用对于全部污水处理过程的最终质量产生了十分重要的影响。因此,潜水推流器成为了污水处理厂重要的搅拌和推流的设备。采用试验与CFD数值模拟相结合的方法研究了直径为400 mm转速为980 r/min推流器的推力、功率以及推功比性能参数,建立三维几何模型,进行结构化网格划分并进行了网格无关性分析,对潜水推流器进行了非定常计算;通过数值计算分析得出安装导流罩的潜水搅拌器的推力为759.33 N,功率为888.29 W,推功比为0.85 N/W,未安装导流罩的潜水搅拌器的推力为1003.39 N,功率为1144.72 W,推功比为0.88 N/W,安装导流罩的潜水推流器的推力、功率以及推功比比未安装导流罩的潜水推流器分别要减小24.3%、22.4%、2.4%,通过试验研究得出安装导流罩的潜水搅拌器的推力为740 N,功率为903 W,推功比为0.82 N/W,未安装导流罩的潜水搅拌器的推力977 N,功率为1164 W,推功比为0.84 N/W,安装导流罩的潜水推流器的推力、功率以及推功比比未安装导流罩的潜水推流器分别要减小24.3%、22.4%、2.4%,推力、功率、推功比的模拟值和试验值的误差在5%以内,数模和试验结果吻合性较好,有效验证了数值模拟的精度和试验的可靠性。导流罩对推流器的有效推进距离有促进作用,有导流罩有效推进距离比没有导流罩在0.3、0.4、0.6m/s条件下分别增加了4.8%、28.4%、30.8%。

While China’s economy has progressed exceedingly rapidly,its adverse impact on the environment has been overlooked,thus re⁃sulting in numerous issues related to environmental contamination,including water resources pollution.The submersible pusher,due to its diminutive size,facile installation process,and excellent maintenance qualities,is capable of being installed within treatment pools of limit⁃ed volumetric capacity.By enabling enhanced processing efficiency within each pool,this approach facilitates system-wide efficiency with⁃out being subject to the limitations of a singular step’s efficiency.During the procedure of wastewater treatment,the submersible mixer plays a paramount role as one of the essential core components.Its performance and function bear a significant impact on the ultimate quality of the entire sewage treatment process.Hence,the subaqueous propeller has emerged as a crucial apparatus that facilitates the process of amalgam⁃ating and propelling fluid within sewage treatment facilities.An integration of experimentation and computational fluid dynamics(CFD)nu⁃merical simulation is employed to investigate the various performance indicators,including thrust,power,and thrust-to-power ratio of a submersible thruster operating at a rotating speed of 980 r/min and having a diameter of 400 mm.Additionally,a three-dimensional geomet⁃ric model is established,followed by the conduction of structured mesh delineation and mesh-independence analysis in order to ensure accu⁃rate simulation results.Finally,non-stationary calculations are conducted on the submersible thruster using the aforementioned methodolo⁃gy.Through numerical calculations,it is determined that the submersible mixer equipped with the deflector generated a thrust of 759.33 N,consumed 888.29 W of power,and yielded a thrust to power ratio of 0.85 N/W.Conversely,the submersible mixer without the deflector pro⁃duced a thrust of 1003.39 N,utilized 1144.72 W of power,and resulted in a thrust to power ratio of 0.88 N/W.The present study examines the impact of a deflector on a submersible thruster’s thrust,power,and thrust-to-power ratio.Results indicate that the inclusion of a deflec⁃tor reduces the aforementioned variables by 24.3%,22.4%,and 2.4%,respectively,as compared to a submersible thruster lacking a deflec⁃tor.Through the experiment,it is determined that the submersible mixer equipped with the deflector generated a thrust of 740 N,consumed 903 W of power,and yields a thrust to power ratio of 0.82 N/W.Conversely,the submersible mixer without the deflector produces a thrust of 977 N,utilized 1164 W of power,and results in a thrust to power ratio of 0.84 N/W.The thrust,power,and thrust-to-power ratio of a submersible thruster with a deflector are reduced by 24.3%,22.4%,and 2.4%,respectively,for a submersible thruster without a deflector.The discrepancy observed in the comparison of the simulated and experimental measurements of thrust,power,and thrust-to-power ratio falls under 5%,hence confirming the reliability of the experimental results and effectively attesting the precision of numerical simulation.The application of a deflector to the thruster has a positive impact on the thruster′s effective propulsive distance.Specifically,when compared to the situation in which a deflector is not applied,the effective propulsive distance increases by 4.8%,28.4%,and 30.8%at velocities of 0.3,0.4,and 0.6 m/s,respectively.