Investigation of friction power consumption and the performance of a water turbine seal based on the imbalanced rotation of magnetic nanofluids

Asian Working Group- IAHR's Symposium on Hydraulic Machinery and Systems

Li, Z.G.^1 ; Zhang, J.R.^1 ; Li, B.^1 ; Liu, X.B.^1 ; Yang, F.Y.^2

Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, China^1

Institute of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, China^2

关键词: Calculated values;    Cooling equipment;    Differential pressures;    Friction power;    Magnetic field gradient;    Magnetic nanofluid;    Magnetic particle;    Nano-fluidic devices;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/163/1/012030/pdf
DOI  :  10.1088/1755-1315/163/1/012030

来源: IOP

【 摘 要 】

The calculation of friction power consumption and the performance of magnetic nanofluids in sealed water turbines have proved to be hurdles in studies on magnetofluidic device designs and applications. In this paper, we investigate the imbalanced rotation ω≠1/2 (rot υ) of a magnetic nanofluid suspended in a paramagnetic carrier liquid. Through Langevin and Navier-Stokes equations, the formula for the theoretical friction power consumption can be calculated for the magnetic particles in the magnetofluid. The calculated value fits the test result. Further simulation indicates that in a sealed magnetic nanofluid device of a water turbine, the magnetic field gradient ΔBsum between the tooth space (wave trough) and the pole tooth (wave crest) has the most influence on the imbalanced rotation. Specifically, the larger the ΔBsum is, the more obviously imbalanced the magnetofluid rotation will be at that location; and the imbalanced torque will be larger, so the seal differential pressure will be obvious as well. As a result, the sealing capacity will be better and the frictional power consumption will be larger; and the reverse is also true. This study result can serve as a reference for designs for sealed magnetic nanofluidic devices for water turbines, which is significant, especially given the heat from friction power consumption in the water turbine and its cooling equipment.