ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-472-4
ISBN Online: 978-1-56700-471-7
3rd Thermal and Fluids Engineering Conference (TFEC)
A MOLECULAR DYNAMIC STUDY OF BOILING ON A NANO DOT DECORATED SOLID SURFACE
Non-equilibrium molecular dynamics simulations have been employed to investigate the effect of nano dots and nanocoating on evaporation and explosive boiling on a hydrophobic solid surface. The molecular system was comprised of three sections: solid copper wall, liquid argon, and argon vapor. A few layers of the liquid argon were placed on the nano dot decorated hydrophobic solid surface. The rest of the simulation box was filled with argon vapor. Initially, the whole system was in equilibrium at 90 K temperature and all of a sudden the temperature of the copper wall was increased which resembles an ultrafast pulse heating. Two different jump temperatures were selected: a few degrees above the boiling point to initiate normal evaporation and far above the critical point to initiate explosive boiling. The simulation results show that, placing a hydrophilic nano dot and introducing hydrophilic coating on a hydrophobic surface, the rate of heat transfer increases and the explosive boiling temperature of liquid argon decrease. Placing nano dots were found more effective to decrease the explosive boiling temperature than introducing hydrophilic nano coatings. The effects of the size of nano dots and nano coatings were also studied, and it was found that explosive boiling temperature tends to decrease with the increase in the size of nano dots.