Heat transfer analysis of different thermal oils in parabolic trough solar collectors with longitudinal sinusoidal internal fin

Abstract

Parabolic trough solar collectors (PTSC) plays an important role in the heating of fluids and in the generation of electricity. In this study, heat transfer and temperature distribution analysis was carried out for the use of internal longitudinal fins with different geometries in a parabolic trough solar collector. Numerical analyzes were carried out for different Reynolds (Re) numbers (2x10 4-8 x10 4) at steady-state conditions and three different thermal oils were used as heat transfer fluid (HTF). The use of the internal fin with sinusoidal lateral surface for all types of thermal oil increased the heat transfer and made the temperature distribution in the fluid more uniform. The highest thermal enhancement factor was occurred for Syltherm 800 oil and sinusoidal fin geometry. With the use of Syltherm 800 oil, the thermal enhancement factor () increased by 40% and 44% respectively according to the Therminol VP1 and D12 oil type for the case with sinusoidal fin.