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Experimental study on effect of different NaCl concentrations and temperature on drag reduction characteristics of Xanthan gum |
LIN Yuying, XU Shengxuan, ZHAO Wenbin, LI Mingyi, LI Changfeng* |
School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China |
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Abstract In order to investigate the drag reduction characteristics of xanthan gum(XG)in NaCl environment and the influence of temperature on the drag reduction performance, the drag reduction cha-racteristics test of xanthan gum solution with different concentrations of NaCl was carried out in a DN20 pipe made of transparent acrylic tube. For different mass fractions of XG solution with NaCl addition(XG/NaCl solution), the relation between the drag reduction efficiency and flow Reynolds number(Re)was obtained and compared with the drag reduction characteristics of XG solution. The result show that in dilute XG solution(0.01%-0.02%), the NaCl concentration has a greater influence on drag reduction rate with different Re, but has less influence on concentrated xanthan solution(0.05%-0.06%). In high NaCl concentration, the drag reduction type B is generally followed when the concentration of XG solution is lower than 0.03%. When the concentration of XG solution is greater than or equal to 0.03%, the solution has the conversion characteristics from type A drag reduction at low Re to type B drag reduction at high Re. The drag reduction rate of XG solution is sensitive to temperature change at low Re, while the drag reduction rate at high Re is less affected by temperature.
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Received: 10 July 2020
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