Publication de 12 numéros par an
ISSN Imprimer: 1044-5110
ISSN En ligne: 1936-2684
Indexed in
n-HEPTANE DROPLET VAPORIZATION USING MOLECULAR DYNAMICS
RÉSUMÉ
The vaporization of a n-heptane (C7H16) droplet is investigated using molecular dynamics (MD). This constitutes one of the first studies of droplet vaporization employing a polyatomic molecule. A torsion potential is employed for intramolecular interactions and a truncated Lennard-Jones (2.5σ) for all intermolecular and a select number of intramolecular interactions. During each integration step the structure of the molecule is maintained by constraining bond lengths and bond angles iteratively, using the RATTLE algorithm. Initial equilibration of the liquid- and gas-phase systems is done separately using an NVT simulation; velocity rescaling is applied for both the internal and translational temperatures. Four simulations are performed on systems composed of a total of 1526, 1529, 3031, and 3041 molecules under pressures of 1 and 2 atm, respectively. This corresponds to a single-species droplet vaporization process occurring in a superheated gaseous environment. Results in terms of molecular-time-averaged forces show noticeable departures from spherical symmetry in the droplet shape. This is attributed in part to the lack of symmetry of the C7H16 molecule, which translates to manifestations at the droplet scale. The Amsterdan method is employed to investigate droplet size histories. Relatively close agreement with D2-law behavior is reported, even though the Knudsen numbers are in an intermediate regime between the kinetic theory and continuum limits.
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Mutoru J. W., Smith W., O’Hern C. S., Firoozabadi A., Molecular dynamics simulations of diffusion and clustering along critical isotherms of medium-chain n-alkanes, The Journal of Chemical Physics, 138, 2, 2013. Crossref
-
Yanagihara Hiromichi, Stanković Igor, Blomgren Fredrik, Rosén Arne, Sakata Ichiro, A molecular dynamics simulation investigation of fuel droplet in evolving ambient conditions, Combustion and Flame, 161, 2, 2014. Crossref
-
Mo Guiyuan, Qiao Li, A molecular dynamics investigation of n-alkanes vaporizing into nitrogen: transition from subcritical to supercritical, Combustion and Flame, 176, 2017. Crossref
-
Sazhin Sergei, Kinetic Modelling of Droplet Heating and Evaporation, in Droplets and Sprays, 2014. Crossref
-
Chakraborty Suman, Qiao Li, Molecular investigation of sub-to-supercritical transition of hydrocarbon mixtures: Multi-component effect, International Journal of Heat and Mass Transfer, 145, 2019. Crossref
-
Sazhin Sergei S., Kinetic Modelling of Droplet Heating and Evaporation, in Droplets and Sprays: Simple Models of Complex Processes, 2022. Crossref