An effective procedure of response surface methodology (RSM) has been successfully developed for a coiled agitated vessel by finding the optimal values of working parameters to achieve the high heat transfer performance. Studies have been performed for two types of agitators, propeller and disk turbine respectively. TiO 2 /water nanofluid has been used as agitated medium. Various operating parameters, such as impeller speed (100–700 rpm for propeller and 100–300 rpm for disk turbine), TiO 2 /water nanofluid concentration (0–0.3 vol%), heat input (400–2200 W) to the agitated medium were explored by experiment. Experiments were performed at desired set of working conditions suggested by a standard RSM design called a Box-Behnken Design. Nusselt number was considered as performance parameter. The results identify the significant influence factors to achieve high coefficient of heat transfer. A set of 690 rpm, 0.28 vol%, 1480 W for propeller and 220 rpm, 0.15 vol%, 1330 W for disk turbine have been suggested by the model for achieving improved heat transfer performances. The obtained optimal working parameters have been predicted and verified by conducting validation experiments. A good agreement of discrepancy ±4% have been obtained between experimental and predicted values.

中文翻译：

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带有 TiO2/水纳米流体的螺旋搅拌容器的参数优化

通过找到工作参数的最佳值来实现高传热性能，已经成功地为螺旋搅拌容器开发了一种有效的响应面法 (RSM) 程序。已经对两种类型的搅拌器进行了研究，分别是螺旋桨和盘式涡轮机。TiO 2 /水纳米流体已被用作搅拌介质。各种运行参数，例如叶轮转速（螺旋桨为 100-700 rpm，盘式涡轮机为 100-300 rpm）、TiO 2 /水纳米流体浓度（0-0.3 vol%）、搅拌器的热输入（400-2200 W）通过实验探索培养基。在称为 Box-Behnken 设计的标准 RSM 设计建议的一组所需工作条件下进行实验。努塞尔数被认为是性能参数。结果确定了实现高传热系数的重要影响因素。该模型建议使用一组 690 rpm、0.28 vol%、1480 W 的螺旋桨和 220 rpm、0.15 vol%、1330 W 的盘式涡轮机，以提高传热性能。通过进行验证实验，预测并验证了获得的最佳工作参数。在实验值和预测值之间获得了良好的差异 ±4%。