Investigation of a nanofluid-based compound parabolic trough solar collector under laminar flow conditions

Abstract

The objective of this work is the investigation of a nanofluid-based compound parabolic collector under laminar flow conditions. The examined nanofluid is Syltherm 800/CuO with 5% volumetric nanoparticle concentration and the examined temperature range is from 25 °C up to 300 °C. The analysis is performed in SolidWorks Flow Simulation Studio using a developed computational fluid dynamics model. Moreover, it is essential to state that this work is conducted under laminar flow conditions because the laminar flow regime is common for the compound parabolic collectors. It is found that the mean value of the thermal efficiency is 1.24% while the maximum 2.76% for inlet temperature equal to 300 °C. Moreover, it is found that the mean and the maximum heat transfer coefficient enhancements were 16.16% and 17.41% respectively, while the maximum pumping work increase was found to be 16.09%. However, the calculated pumping work demand was too low in all cases and this fact indicates that the increase of the pressure drop with the nanofluid is not a limitation in the present problem. In the end, the exergy efficiency enhancement is found to be up to 2.60%, while the overall efficiency enhancement up to 2.76% with the use of nanofluid.