A review on the heat and mass transfer phenomena in nanofluid coolants with special focus on automotive applications

Engineered suspensions of nanosized particles (nanofluids) are characterized by superior thermal properties. Due to the increasing need for ultrahigh performance cooling in many industries, nanofluids have been widely investigated as next-generation coolants. However, the multiscale nature of nanofluids implies nontrivial relations between their design characteristics and the resulting thermo-physical properties, which are far from being fully understood. This pronounced sensitivity is the main reason for some contradictory results among both experimental evidence and theoretical considerations presented in the literature. In this Review, the role of fundamental heat and mass transfer mechanisms governing thermo-physical properties of nanofluids is assessed, from both experimental and theoretical point of view. Starting from the characteristic nanoscale transport phenomena occurring at the particle-fluid interface, a comprehensive review of the influence of geometrical (particle shape, size and volume concentration), physical (temperature) and chemical (particle material, pH and surfactant concentration in the base fluid) parameters on the nanofluid properties was carried out. Particular focus was devoted to highlight the advantages of using nanofluids as coolants for automotive heat exchangers, and a number of design guidelines was suggested for balancing thermal conductivity and viscosity enhancement in nanofluids. This Review may contribute to a more rational design of the thermo-physical properties of particle suspensions, therefore easing the translation of nanofluid technology from small-scale research laboratories to large-scale industrial applications

"Meme-Spirited”: I. The VAPUS Model for Understanding the Prevalence and Potency of Ghost Narratives.

Abstract: A review of nearly 20 years of sociocultural research and trends on “ghostly episodes” (ghosts, haunted houses, and poltergeists) suggests that personal accounts, group investigations, and popular depictions of anomalous experiences function as active, meaningful, and potent cultural memes. These, in part, reflect interpersonal or group dynamics grounded in Durkheimian models, as well as Social Identity and Conflict theories. Expanding on and integrating these themes, this paper provides a general framework that explains the enduring popularity of ghost narratives in terms of their versatility, adaptability, participatory nature, universality, and scalability (VAPUS model). This perspective implies that ghostly episodes, as experiences and narratives, embody and exemplify the marketing concepts of “brand personality” and consumer engagement. Accordingly, social and cultural influences are discussed as important and inherent contextual variables that help to produce, promote, shape, and sustain these narratives