This study investigates the combioned effect of low-frequency vibrations and heat transfer fluid on the fluid outlet temperature of flat plate solar collectors (FPSC).Low-frequency vibrations in the range of 5�10 Hz with a constant amplitude of 3 mm were applied on the FPSC having water (H2O) and Aluminum Oxide (Al2O3�H2O) water nanofluid as HTF.Computational Fluid Dynamics (CFD) study was carried out to simulated FPSC and the model validated with the experimental results from the literature.The results showed a noticeable enhancement in the fluid outlet temperature of FPSC after applying vibrations.With water as HTF, the fluid outlet temperature without vibrations was 41.4 °C, while by applying low-frequency vibrations of 5 and 10 Hz, it increased to 48.7 °C and 49.5 °C respectively.While with Aluminum Oxide (Al2O3�H2O) water nanofluid as HTF, the fluid outlet temperature without vibrations was 50.68 °C while by applying low-frequency vibrations of 5 and 10 Hz, it increased to 51.3 °C and 52.5 °C respectively. © 2023, Institute of Technology PETRONAS Sdn Bhd.