The influence of the geometric shape of the symmetrical twisted turbulator on the performance of parabolic solar collector having hybrid nanofluid: Numerical approach using two-phase model

Abstract

In this investigation, the influence of twisted turbulator and water-based MWCNT-MgO hybrid nanofluid on thermal–hydraulic performance (PEC), energy efficiency (ηn), and exergy efficiency (ηex) of parabolic solar collectors (PSCs) was numerically investigated using the finite volume process. The two-phase nanofluid flows at the Reynolds number (Re) ranging of 10,000–25,000, the RNG k-ε turbulence model is used to model the turbulent flow regime. The nanofluid is modeled by a two-phase mixed model. In addition, the SIMPLEC algorithm was used for simulation. The study is performed for nanoparticles concentrations (φ) of 1% to 3% and pitch ratios (PR) of 0.25, 0.5, 0.75, and 1. Re and φ of MWCNT and MgO nanoparticles were detected to augments (Nuav). It is detected that the values ​​of PEC are more than 1 for all cases. Therefore, it can be concluded that using a twisted turbulator and an enhancement of its PR intensifies PEC. In addition, the results demonstrate that ηn is enhanced and ηex is reduced with the PR of the solar collector having twisted. For case of φ = 3%, as Re increased from 10,000 to 25,000, ηnandηex are enhanced by 45.98% and 31.67% for PR = 1 and 0.25, respectively.