In this paper, the hydrodynamic and thermal behavior of a Fe₃O₄ ferrofluid flow was experimentally investigated inside a cupric u-shaped tube on a horizontal surface, under the effect of a variable magnetic field. The inlet flow regime was laminar and considered under the thermal boundary conditions of the tube with a uniform heat flux, which was affected by the variable magnetic field in some regions. The purpose of the study was to investigate the effect of parameters such as volume fraction of nanoparticles, Reynolds number of the flow, the radius of the curvature, and magnetic field frequency at three levels and four factors in the flow behavior in order to increase the convection heat transfer coefficient. The analyses were carried out separately for three regions of the tube, namely straight inlet section, tube curvature section, and straight outlet section following Taguchi method of experiment design and ANOVA. Results of ANOVA showed that changes in Reynolds number in the curvature of the tube had the greatest effect (82.88%) in increasing the convection heat transfer coefficient. However, this parameter affected straight sections of the inlet and outlet tube by 69.61% and 73.47%, respectively. In addition, the minimum influence on increasing convection heat transfer coefficient was observed with frequency parameter, which had its effect on a straight section of the inlet tube, curvature section of the tube, and straight section of the outlet tube by 1.48%, 0.66%, and 0.7%, respectively.

在本文中，Fe ₃ O ₄的水动力和热行为在可变磁场的作用下，通过实验研究了铁磁流体在水平表面上的U型铜管内部的流动。入口流态是层流的，并在具有均匀热通量的管的热边界条件下考虑，这在某些区域受可变磁场的影响。该研究的目的是研究诸如纳米颗粒的体积分数，流的雷诺数，曲率半径和磁场频率等参数在流动行为的三个级别和四个因素上的影响，以增加流动性。对流换热系数。对试管的三个区域分别进行了分析，即直进段，试管弯曲段，和直出口段遵循田口的实验设计方法和方差分析。方差分析的结果表明，管对曲率的雷诺数变化对对流传热系数的影响最大（82.88％）。但是，此参数分别影响入口管和出口管的直线段，分别影响69.61％和73.47％。另外，用频率参数对增加对流换热系数的影响最小，对进口管的直截面，管的曲率截面和出口管的直截面的影响分别为1.48％，0.66％。 ，分别为0.7％。但是，此参数分别影响入口管和出口管的直线段，分别影响69.61％和73.47％。另外，用频率参数对增加对流换热系数的影响最小，对进口管的直截面，管的曲率截面和出口管的直截面的影响分别为1.48％，0.66％。 ，分别为0.7％。但是，此参数分别影响入口管和出口管的直线段，分别影响69.61％和73.47％。另外，频率参数对增加对流换热系数的影响最小，对进口管的直截面，管的曲率截面和出口管的直截面的影响分别为1.48％，0.66％。 ，分别为0.7％。