38 research outputs found
Surface Engineering for Phase Change Heat Transfer: A Review
Among numerous challenges to meet the rising global energy demand in a
sustainable manner, improving phase change heat transfer has been at the
forefront of engineering research for decades. The high heat transfer rates
associated with phase change heat transfer are essential to energy and industry
applications; but phase change is also inherently associated with poor
thermodynamic efficiencies at low heat flux, and violent instabilities at high
heat flux. Engineers have tried since the 1930's to fabricate solid surfaces
that improve phase change heat transfer. The development of micro and
nanotechnologies has made feasible the high-resolution control of surface
texture and chemistry over length scales ranging from molecular levels to
centimeters. This paper reviews the fabrication techniques available for
metallic and silicon-based surfaces, considering sintered and polymeric
coatings. The influence of such surfaces in multiphase processes of high
practical interest, e.g., boiling, condensation, freezing, and the associated
physical phenomena are reviewed. The case is made that while engineers are in
principle able to manufacture surfaces with optimum nucleation or thermofluid
transport characteristics, more theoretical and experimental efforts are needed
to guide the design and cost-effective fabrication of surfaces that not only
satisfy the existing technological needs, but also catalyze new discoveries