CFD analysis of rib roughened solar evacuated tube collector for air heating. (January 2022)

• Record Type: Journal Article
• Authors: Singla, Mohit; Hans, Vishavjeet Singh; Singh, Sukhmeet
• Is Part Of: Renewable energy. Volume 183(2022)
• Page Start: 78
• Page End: 89
• Publication Date: 2022-01
• Subjects: Nusselt number -- Friction factor -- Solar evacuated tube collector -- Thermo-hydraulic performance -- Heat transfer augmentation techniques -- Rib roughness; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2021.10.055
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: Using Computational Fluid Dynamics analysis, thermo-hydraulic performance of a rib roughened solar evacuated tube collector has been evaluated for different relative roughness pitch and mass flow rate values. Half portion of absorber tube is roughened and heated uniformly with a heat input of 1000 W/m 2 . The investigated roughness geometry parameters include relative roughness pitch (P/e) of the order 6–12 whereas relative roughness height is having a fixed value of 0.071. Reynolds number was varied from 2500 to 8000. In contrast to a smooth solar evacuated tube collector, Nusselt number and frictional resistance of a roughened solar evacuated tube collector increased by 1.88 and 2.89 times respectively. Thermo-hydraulic performance parameter of roughened solar evacuated tube collector was found to be 1.36 corresponding to Reynolds number and P/e values of 8000 and 10 respectively which indicates considerable benefit of applying rib roughness in a solar evacuated tube collector. Highlights: 1. Developed artificially roughened evacuated tube collector solar air heater. 2. Achieved maximum enhancement of order 1.88 times for Nusselt number. 3. Achieved maximum value of 1.36 for thermo-hydraulic performance parameter.