The current investigation numerically scrutinizes exergy loss and heat transfer of mixture of Aluminum oxide and H2O through a solar collector. Finite volume method has been employed with considering realizable k - epsilon. Such turbulence model has been selected because of best agreement with previous experimental outputs. To assure the accuracy of code, comparisons with numerical and experimental outputs have been provided for different Reynolds number (Re), number of revolution (N) and diameter ratio (D*). Dispersing Al2O3 is apparently able to offer a more promotion on second law's performance. More turbulence mixing occurs when employing a turbolentor with extra revolution. As diameter ratio augments, exergy loss drops due to reduction of surface temperature. Increasing inlet velocity brings about a significant reduction in surface temperature which results in less exergy loss. (C) 2019 Elsevier Ltd. All rights reserved.