Library Open Repository

Computational fluid dynamics modelling of residual fuel oil combustion in the context of marine diesel engines

Downloads

Downloads per month over past year

Goldsworthy, L (2006) Computational fluid dynamics modelling of residual fuel oil combustion in the context of marine diesel engines. International Journal of Engine Research, 7 (2). pp. 181-199. ISSN 1468-0874

[img] PDF
47110_IJER_2006...pdf | Request a copy
Full text restricted
Available under University of Tasmania Standard License.

Abstract

A simplified model is presented for vaporization and combustion of heavy residual
based fuel oil in high-pressure sprays, in the context of marine diesel engines. The fuel is
considered as a mix of residual base and cutter stock. The model accounts for multiple fuel components
as well as limited diffusion rates and thermal decomposition rates within droplets by
the use of straight-line relationships for the saturation pressure of combustible fuel vapour at
the droplet surface as functions of droplet temperature. The energy required for decomposition
of heavy molecules is accounted for. Combustion is modelled using a timescale that is the
sum of a kinetic timescale based on a single-step reaction and a turbulent timescale based on
turbulent mixing rates. The ignition timescale is based on a simple three-equation model.
Cellwise ignition is employed. The heavy fuel oil model is applied to two different constant
volume chambers that are used to test ignition and combustion quality of marine heavy fuel
oil, using the computational fluid dynamics code StarCD version 3.2. Good agreement is shown
between trends in measured and computed data including ignition delay, burn rate and spatial
distribution of spray and flame parameters. The model is tested for two representative fuels,
one with good ignition and combustion properties and one poor. Essentially only two parameters
need to be changed to set the fuel quality. These are the ignition delay factor and the
activation energy for the high-temperature kinetics. Further tuning of the model to specific
fuels is possible by modifying the saturation temperature relationships.

Item Type: Article
Keywords: heavy residual fuel oil, droplet vaporization and decomposition model, ignition and combustion quality, multiple fuel components, marine diesel engines, CFD
Journal or Publication Title: International Journal of Engine Research
Page Range: pp. 181-199
ISSN: 1468-0874
Identification Number - DOI: 10.1243/146808705X30620
Date Deposited: 29 Nov 2007 23:30
Last Modified: 18 Nov 2014 03:25
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page