Study of Pool Boiling Heat Transfer on Concave Nanostructured Surface With Molecular Dynamics Simulation

Abstract The nanoscale boiling phenomena on solid surface is significantly distinct from that at macroscale. In this work, the pool boiling process of liquid argon thin film on smooth/concave aluminum surfaces were simulated using non-equilibrium molecular dynamics (NEMD) simulation, in which the nonuniform hydrophilic/hydrophobic surfaces were considered. For each surface, the superheat degree was progressively increased and the MD simulations were carried out to record the variation of atomic motion trajectory, mass density, the number of vapor and liquid atoms, kinetic energy and internal energy as time elapses. The predictions show that heat flux can reach critical heat flux (CHF) with increasing of wall superheat degree. Under the same superheat degree, the hydrophilic surface has the higher heat flux value than the hydrophobic surface, but it is earlier to reach CHF compared to the hydrophobic one. In addition, it also demonstrates that, with the same surface morphology, liquid-solid interaction strength has a significant influence on the heat transfer transition from nucleate boiling to film boiling. The surface morphology has more favorable effect on the pool boiling compared to the surface wettability at nanoscale. The obtained results in this work can guide the design and fabrication of enhanced heat transfer surface with nanostructured modification.