Prediction and evaluation of energy and exergy efficiencies of a nanofluid-based photovoltaic-thermal system with a needle finned serpentine channel using random forest machine learning approach

The Photovoltaic thermal (PVT) collector performance is numerically investigated considering the effect of using needle fins in the serpentine channel with Nanofluid (NF). The influence of increasing the nanoparticle con-centration (phi) and Reynolds number (Re) on the energy and exergy features of the PVT device is examined. A comparison is made between the hydrothermal characteristics of the PVT with the finned and plain serpentine channels. The utilization of needle fins improves the thermal efficiency (eta th), electrical efficiency (eta el), and overall efficiency (eta el) by 8.56-10.22%, 0.13-0.24%, 5.12-5.67%, respectively, against the PVT with the plain serpentine channel. Moreover, thermal exergy efficiency (xi th), electrical exergy efficiency (xi el), and overall exergy efficiency (xi ov) by 8.56-1.22%, 0.13-0.24%, and 2.61-2.79%, respectively, versus the PVT with the plain serpentine channel. Moreover, the Random Forest (RF) machine learning approach is used to develop a pre-dictive model for eta th, eta el, eta el, xi th, xi el and xi ov in terms of Re and phi. The outcomes of modeling proved that all the results were in an acceptable level of accuracy and the overall efficiency in both energy and exergy yielded superior precision in comparison with the other targets.