Heat transfer intensifications, therefore, are in two categories. The passive category focuses on the external powers of systems while the active category emphasizes rotational effects. Passive techniques incorporate the host equipment enhancement techniques. These techniques include coating surfaces, surface catalysis, and porous structures, among others (Kearney, 1999).
Passive enactments are characterized by the coatings that are applied to surfaces to promote transformations of fluids to liquid or steam. In addition to that, it has been demonstrated that dropwise condensation of fluids comes with positive benefits overall. It sustains endothermic processes within these systems and leads to optimum heat intensifications. In addition to that, coating surfaces also intensify the heat and mass transfer and make them act as catalysts.