skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Joint scalar transported PDF modeling of nonpiloted turbulent diffusion flames

Abstract

A transported joint probability density function (JPDF) approach closed at the joint scalar level has been applied to investigate two nonpiloted CH{sub 4}/H{sub 2}/N{sub 2} turbulent (Re 15200 and 22800) jet diffusion flames. The flames have been studied experimentally at the Deutsches Zentrum fur Luft- und Raumfahrt (DLR) and at Sandia National Laboratories and are well characterized experimentally through extensive velocity and scalar measurements. The flames offer the opportunity of computational investigations of turbulence-chemistry interactions in CH{sub 4}/H{sub 2} flames in the absence of both partial premixing with air and with a smaller stoichiometric mixture fraction (Z{sub st}=0.167) than in the corresponding piloted Sandia flames. The two flames also offer different levels of local extinction. Comparatively few theoretical studies have been performed of these flames and the present work provides an assessment of the ability of the transported PDF approach to reproduce their detailed thermochemical structure. The chemical closure is obtained through a systematically reduced C/H/O/N mechanism featuring 16 independent, 4 dependent, and 28 steady-state scalars. The velocity field is computed using the second moment closure of Speziale et al. and molecular mixing is modeled using the modified Curl's model. It is shown that velocity and scalar fields are generallymore » well reproduced for 10=<x/D=<80 though uncertainties in boundary conditions have an impact closer to the burner exit.« less

Authors:
;  [1]
  1. Thermofluids Division, Department of Mechanical Engineering, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AZ (United Kingdom)
Publication Date:
OSTI Identifier:
20681465
Resource Type:
Journal Article
Resource Relation:
Journal Name: Combustion and Flame; Journal Volume: 143; Journal Issue: 4; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; FLAMES; MATHEMATICAL MODELS; METHANE; HYDROGEN; NITROGEN; TURBULENCE; COMBUSTION KINETICS

Citation Formats

Lindstedt, R.P., and Ozarovsky, H.C.. Joint scalar transported PDF modeling of nonpiloted turbulent diffusion flames. United States: N. p., 2005. Web. doi:10.1016/j.combustflame.2005.08.030.
Lindstedt, R.P., & Ozarovsky, H.C.. Joint scalar transported PDF modeling of nonpiloted turbulent diffusion flames. United States. doi:10.1016/j.combustflame.2005.08.030.
Lindstedt, R.P., and Ozarovsky, H.C.. Thu . "Joint scalar transported PDF modeling of nonpiloted turbulent diffusion flames". United States. doi:10.1016/j.combustflame.2005.08.030.
@article{osti_20681465,
title = {Joint scalar transported PDF modeling of nonpiloted turbulent diffusion flames},
author = {Lindstedt, R.P. and Ozarovsky, H.C.},
abstractNote = {A transported joint probability density function (JPDF) approach closed at the joint scalar level has been applied to investigate two nonpiloted CH{sub 4}/H{sub 2}/N{sub 2} turbulent (Re 15200 and 22800) jet diffusion flames. The flames have been studied experimentally at the Deutsches Zentrum fur Luft- und Raumfahrt (DLR) and at Sandia National Laboratories and are well characterized experimentally through extensive velocity and scalar measurements. The flames offer the opportunity of computational investigations of turbulence-chemistry interactions in CH{sub 4}/H{sub 2} flames in the absence of both partial premixing with air and with a smaller stoichiometric mixture fraction (Z{sub st}=0.167) than in the corresponding piloted Sandia flames. The two flames also offer different levels of local extinction. Comparatively few theoretical studies have been performed of these flames and the present work provides an assessment of the ability of the transported PDF approach to reproduce their detailed thermochemical structure. The chemical closure is obtained through a systematically reduced C/H/O/N mechanism featuring 16 independent, 4 dependent, and 28 steady-state scalars. The velocity field is computed using the second moment closure of Speziale et al. and molecular mixing is modeled using the modified Curl's model. It is shown that velocity and scalar fields are generally well reproduced for 10=<x/D=<80 though uncertainties in boundary conditions have an impact closer to the burner exit.},
doi = {10.1016/j.combustflame.2005.08.030},
journal = {Combustion and Flame},
number = 4,
volume = 143,
place = {United States},
year = {Thu Dec 01 00:00:00 EST 2005},
month = {Thu Dec 01 00:00:00 EST 2005}
}