An experimental analysis is performed for a wide range of operating and device parameters to analyze artificial roughness effects on heat transfer and friction characteristics in solar air heater (SAH) ducts with inline and staggered cube-shaped roughness arranged on the absorber surface. In this investigation, cube shaped roughness elements are used to achieve superior characteristics of heat transfer. However, due to high friction, this improvement throughout particular is accompanied by high pumping power. Experiments are conducted for a range of Reynolds number (Re) from 3000 to 8,000, relative roughness pitch (p/e) from 10 to 20 and relative roughness gap (w/e) from 4 to 8. Relative roughness height (e/D_h) of 0.06 and aspect ratio (W/H) value of 5 are retained as constants. A significant improvement is achieved in the Nusselt number (59.1-72.7%) along with a large increase in the friction factor (138.7-179.4%) over SAH with a smooth absorber surface. The experimental data are used as a function of artificial roughness parameters and operating parameters to develop friction factor and Nusselt number correlations.

对各种操作和设备参数进行了实验分析，以分析人工粗糙度对太阳能空气加热器（SAH）管道中传热和摩擦特性的影响，在吸收器表面上排列有交错的交错立方体形状的粗糙度。在这项研究中，使用了立方体形状的粗糙元件来实现出色的传热特性。然而，由于高摩擦，特别是这种改进伴随着高泵浦功率。实验范围为雷诺数（R e）为3000至8,000，相对粗糙度间距（p / e）为10至20，相对粗糙度间隙（w / e）从4到8。相对粗糙度高度（e / D _h）为0.06，纵横比（W / H）值为5保留为常数。与具有光滑吸收体表面的SAH相比，Nusselt值（59.1-72.7％）显着提高，摩擦系数大大提高（138.7-179.4％）。实验数据被用作人工粗糙度参数和操作参数的函数，以发展摩擦系数和努塞尔数相关性。