Heat transfer enhancement analysis of parabolic trough collector with straight and helical absorber tube. (1st December 2020)

• Record Type: Journal Article
• Authors: Chakraborty, Oveepsa; Das, Biplab; Gupta, Rajat; Debbarma, Sumita
• Is Part Of: Thermal science and engineering progress. Volume 20(2020)
• Publication Date: 2020-12-01
• Subjects: Nanofluid -- Solar collector -- Spiral absorber -- Energy -- Exergy; Heat engineering -- Periodicals; Heat engineering; Thermodynamics; Periodicals; 621.402
• DOI: 10.1016/j.tsep.2020.100718
• Languages: English
• ISSNs: 2451-9049

Abstract

Highlights: The absorber tube of PTC is modified with internal helical turns. Three models of 15, 20, and 25 helical turns are compared for Al2 O3 -H2 O with H2 O. Volume fraction for Al2 O3 -H2 O is taken as 0.09. Nusselt number is enhanced by 4.54% to 36% for Al2 O3 -H2 OAl2 O3 -H2 O against H2 O. Thermal efficiency and exergy increases by 1%-10% and 0.2%-3.2% respectively. Abstract: The use of a helical tube absorber concerning parabolic trough collector (PTC) is a promising technique for environmental-friendly energy generating system. The aim of this study is to analyze the thermal behavior of the absorber tube with and without turns by considering water as well as Al2 O3 based water as working fluids by varying mass flow rate 0.025–0.25 kg/s. All 4 cases are analyzed in ANSYS 14 (Design Modeler): three models for helical absorber tube with number of turns 15, 20, and 25, and another model with smooth absorber tube. It is observed that the thermal, exergy, and overall efficiency are higher with higher number of turns. Further, use of nanofluid of volume fraction 0.09, the thermal efficiency enhancement is around 1–10% and exergy as well as overall efficiency are increased by around 0.2%-3.2% and 1%-9% respectively in comparison to water as working fluid.