Experimental investigation and CFD modeling of the dynamics of bubbles in nanofluid pool boiling

This work investigated the dynamics of bubbles in pool boiling of nanofluid with coated and sodium dodecyl sulfate (SDS) solution with different nanoparticles. Also, computational fluid dynamics (CFD) module was used for mathematical modeling of bubbles in pure water boiling. Different macroscale parameters such as: shapes, numbers and contact angle of bubbles also were investigated experimentally and verified by CFD modeling results. Porous layers of nanoparticles on stainless steel substrate in conjunction with SDS additions were shown to modify formation of bubbles in comparison to reference condition. Improvement in surface hydrophilic conditions and boiling performance was observed by Multi-wall Carbon Nanotube (MWCNT) porous layers, in spite of coated surface by CuO and Al2O3 (gamma) water based nanofluid. Growth time of bubbles also changes by the presence of porous layers and surfactant solution which resulted from change in surface tension force. Number of bubbles increased by MWCNT and SDS solution and decreased by CuO and Al2O3 nanofluid boiling. Results showed the comprehensive change in bubble dynamics and surface wettability by porous layer of nanoparticles and SDS solution. (C) 2014 Elsevier Ltd. All rights reserved.