A thorough analysis of surfactant addition effects on the thermophysical properties and stability of nanofluids

Researchers are mainly suggesting that optimizing the heat efficiency of thermal apparatus by dispersing nanoparticles into the foundation fluid will boost its heat efficiency in boiling sectors. Many investigators conduct research on factors such as fluid properties, bubble growth and bubble dynamics, heater surface effect, and so forth. However, the problem of deficiency in stability created by nanoparticle sedimentation or agglomeration into the base fluid over time has restricted practicable applications, which has drawn considerable attention in recent years. To overcome that, many researchers used a common technique, the addition of stabilizing agents like surfactants/additives into the nanofluids (NFs) to achieve stability. Understanding the behavior of surfactants in NFs and their effect on various important physical properties of the working fluid is required. In this review, firstly discuss the impact of adding surfactants on the stability of an aqueous solution. Additionally, it provides a concise assessment of how the inclusion of surfactants affects different thermal physical characteristics like interfacial tension, viscosity, and thermal conductivity of aqueous solutions or NFs. Finally, it outlines the primary obstacles and challenges encountered by researchers that continue to be areas of focus for future investigations concerning NFs containing surfactants.