Parametric Study of the Flow in the Horizontal Absorber Tube of the Parabolic Trough Collector

The inability of base fluid to carry a sufficient amount of thermal energy to the storage system or power block has encouraged researchers to improve the performance of base fluid by adding particles suspended in the base fluid to improve the thermal properties of the resulting fluid (nanofluid). Besides, several options can be used for improving heat transfer associated with internal flow inside a solar receiver. This augmentation in convection heat transfer can be obtained by increasing the convection heat transfer coefficient and /or by increasing the convection surface area. Inducing swirl by twisted tape inside the receiver enhances the convection heat transfer coefficient. In this paper, an indoor test rig has been designed and manufactured for this purpose. A measuring technique has been implemented and executed for measuring all parameters regarding heat transfer and fluid flow to simulate the outdoor test rig of the parabolic trough absorbing tube. The measuring technique shows that the error is less than 1 percentage, In addition, nonuniform heat