Library Subscription: Guest
ICHMT DL Home Current Year Archives Executive Committee International Centre for Heat and Mass Transfer

KINETIC AND MOLECULAR DYNAMICS SIMULATIONS OF N-DODECANE DROPLET HEATING AND EVAPORATION

DOI: 10.1615/ICHMT.2012.CHT-12.600
pages 981-992

Jian-Fei Xie
Sir Harry Ricardo Laboratories, School of Computing, Engineering and Mathematics, University of Brighton, Cockcroft Building, Brighton BN2 4GJ, UK

Sergei S. Sazhin
Advanced Engineering Centre, School of Computing, Engineering and Mathematics, University of Brighton, Brighton, BN2 4GJ, UK

Irina N. Shishkova
Low Temperature Departments, Centre of High Technologies, Moscow Power Engineering Institute, Krasnokazarmennaya, 14, Moscow 111250, Russia

Bing-Yang Cao
Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Engineering Mechanics, Tsinghua University, Beijing, China

Abstract

Results of recent developments in kinetic and molecular dynamics simulations of n-dodecane droplet heating and evaporation are summarised. The effect of inelastic collisions between two molecules on the solution of the Boltzmann equation is taken into account by presenting the change of state of molecules after collisions as a random movement along the surface of an N-dimensional sphere, the squared radius of which is equal to the total energy of the molecules before and after the collision in the reference system of the centre of mass. The kinetic energies of two molecules are described by the first six dimensions of the system, and the remaining (N-6) dimensions describe the internal energies. This analysis is complemented by molecular dynamics simulations of the evaporation and condensation of liquid n-dodecane (C12H26), the closest approximation to Diesel fuel. The interactions within a molecule and between molecules are calculated using an optimised potential for liquid simulation (OPLS). The evaporation/condensation coefficient is estimated and the results are shown to be compatible with the estimates based on the previous molecular dynamics (MD) simulations and the transition state theory. The velocity distribution functions of molecules at the liquid-vapour equilibrium state are found in the liquid phase, the interface, and the vapour phase. The functions in these three phases are found to be close to isotropic Maxwellian for velocity components parallel to the interface. The function in the vapour phase is found to be close to bi-Maxwellian with the temperature for the velocity component normal to the interface being larger than that parallel to the interface. Both kinetic and molecular dynamics models, described above, are recommended to be used for the analysis of heating and evaporation of n-dodecane droplets in conditions relevant to Diesel engines.

ICHMT Digital Library

Bow shocks on a jet-like solid body shape. Thermal Sciences 2004, 2004. Pulsed, supersonic fuel jets - their characteristics and potential for improved diesel engine injection. PULSED, SUPERSONIC FUEL JETS - THEIR CHARACTERISTICS AND POTENTIAL FOR IMPROVED DIESEL ENGINE INJECTION
View of engine compartment components (left). Plots of temperature distributions in centreplane, forward of engine (right). CHT-04 - Advances in Computational Heat Transfer III, 2004. Devel... DEVELOPMENT AND CURRENT STATUS OF INDUSTRIAL THERMOFLUIDS CFD ANALYSIS
Pratt & Whitney's F-135 Joint Strike Fighter Engine under test in Florida is a 3600F class jet engine. TURBINE-09, 2009. Turbine airfoil leading edge stagnation aerodynamics and heat transfe... TURBINE AIRFOIL LEADING EDGE STAGNATION AERODYNAMICS AND HEAT TRANSFER - A REVIEW
Refractive index reconstructed field. (a) Second iteration. (b) Fourth iteration. Radiative Transfer - VI, 2010. Theoretical development for refractive index reconstruction from a radiative ... THEORETICAL DEVELOPMENT FOR REFRACTIVE INDEX RECONSTRUCTION FROM A RADIATIVE TRANSFER EQUATION-BASED ALGORITHM
Two inclusion test, four collimated sources. Radiative Transfer - VI, 2010. New developments in frequency domain optical tomography. Part II. Application with a L-BFGS associated to an inexa... NEW DEVELOPMENTS IN FREQUENCY DOMAIN OPTICAL TOMOGRAPHY. PART II. APPLICATION WITH A L-BFGS ASSOCIATED TO AN INEXACT LINE SEARCH