Abstract
The use of nanofluids in the cooling system of hybrid solar collectors is an urgent task of intensification of heat transfer. This heat carrier allows for more efficient cooling of the surface of the solar panel, which increases the productivity of the collector. However, the low stability of the nanofluid, manifested in the agglomeration of nanoparticles and their subsequent precipitation, affects the deterioration of the thermophysical properties. This article discusses the sedimentation process of TiO2-double distilled water nanofluid stabilized with CTAB and SDBS surfactants. The sedimentation process was monitored by UV-vis spectroscopy. A high stabilizing effect was observed with the use of CTAB surfactant, expressed in a low sedimentation rate compared to use of SDBS.