An enclosed rotating disk apparatus (RDA) with rotational speed up to 5,500 rpm and with temperature control from -5 to 55 degrees C was designed to screen the turbulent drag reducing effectiveness of small samples of newly synthesized drag reducing additives. First, the rotating disk was calibrated with water using both logarithmic and power law models. Then experiments were carried out to measure the frictional torque reduction for a drag reducing aqueous cationic surfactant system (5 mM Ethoquad O12 with 12.5 mM sodium salicylate) over a range of Re. The maximum drag reduction at 30 degrees C was about 47% at Re = 1.90 x 10(6). For the first time, results with the RDA were compared with those in a circular pipe flow system. They showed similar trends indicating it is a useful screening device for small samples, giving conservative estimates of surfactant effectiveness compared with pipe flow.
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机译：设计了一种封闭式旋转磁盘设备（RDA），其转速高达5500 rpm，温度控制范围为-5到55摄氏度，以筛选新合成的减阻添加剂小样本的湍流减阻效果。首先，使用对数和幂定律模型用水对转盘进行校准。然后进行实验以测量在Re范围内的减阻水性阳离子表面活性剂系统（5 mM Ethoquad O12和12.5 mM水杨酸钠）的摩擦转矩降低。 Re = 1.90 x 10（6）时，在30摄氏度时的最大减阻约为47％。首次将RDA的结果与圆形管道流系统的结果进行了比较。他们显示出相似的趋势，表明它是用于小样品的有用的筛选设备，与管道流量相比，保守估计了表面活性剂的有效性。
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