DNS study of dependence of bulk consumption velocity in a constant-density reacting flow on turbulence and mixture characteristics
(2017) In Physics of Fluids 29(6).- Abstract
3D Direct Numerical Simulation (DNS) study of propagation of a single-reaction wave in forced, statistically stationary, homogeneous, isotropic, and constant-density turbulence was performed in order to evaluate both developing Ut T and fully developed Us T bulk turbulent consumption velocities by independently varying a ratio of 0.5 ≤ u'=SL ≤ 90 of the r.m.s. turbulent velocity to the laminar wave speed and a ratio of 0.39 ≤ L11=δF ≤ 12.5 of the longitudinal integral length scale of the turbulence to the laminar wave thickness. Accordingly, the Damköhler Da = (L11SL)=(u'δF) and Karlovitz Ka = δF=(SLτη) numbers were... (More)
3D Direct Numerical Simulation (DNS) study of propagation of a single-reaction wave in forced, statistically stationary, homogeneous, isotropic, and constant-density turbulence was performed in order to evaluate both developing Ut T and fully developed Us T bulk turbulent consumption velocities by independently varying a ratio of 0.5 ≤ u'=SL ≤ 90 of the r.m.s. turbulent velocity to the laminar wave speed and a ratio of 0.39 ≤ L11=δF ≤ 12.5 of the longitudinal integral length scale of the turbulence to the laminar wave thickness. Accordingly, the Damköhler Da = (L11SL)=(u'δF) and Karlovitz Ka = δF=(SLτη) numbers were varied from 0.01 to 24.7 and from 0.36 to 587, respectively. Here, τ is the Kolmogorov time scale. The obtained DNS data show that, at sufficiently low Da, the fully developed ratio of Us T/u' is mainly controlled by Da and scales as p Da. However, such a scaling should not be extrapolated to high Da. The higher Da (or the lower Ka), the less pronounced dependence of Us T/u' on a ratio of L11/δF. Moreover, scaling laws UT α u'αS1-α L(L11=δF)β are substantially different for developing Ut T and fully developed Us T , i.e., the scaling exponents α and, especially, β depend on the wave-development time. Furthermore, α and, especially, depend on a method used to evaluate the developing Ut T . Such effects can contribute to significant scatter of expressions for UT or ST as a function of (u', SL, L11, δF), obtained by parameterizing various experimental databases.
(Less)
- author
- Yu, Rixin LU and Lipatnikov, Andrei N.
- organization
- publishing date
- 2017-06-01
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physics of Fluids
- volume
- 29
- issue
- 6
- article number
- 065116
- publisher
- American Institute of Physics (AIP)
- external identifiers
-
- wos:000404636900045
- scopus:85021856287
- ISSN
- 1070-6631
- DOI
- 10.1063/1.4990836
- language
- English
- LU publication?
- yes
- id
- 9cd86f62-f699-41fd-985b-2fabb177c76a
- date added to LUP
- 2017-07-24 12:30:39
- date last changed
- 2025-03-17 22:12:29
@article{9cd86f62-f699-41fd-985b-2fabb177c76a, abstract = {{<p>3D Direct Numerical Simulation (DNS) study of propagation of a single-reaction wave in forced, statistically stationary, homogeneous, isotropic, and constant-density turbulence was performed in order to evaluate both developing U<sup>t</sup> <sub>T</sub> and fully developed U<sup>s</sup> <sub>T</sub> bulk turbulent consumption velocities by independently varying a ratio of 0.5 ≤ u'=S<sub>L</sub> ≤ 90 of the r.m.s. turbulent velocity to the laminar wave speed and a ratio of 0.39 ≤ L11=δF ≤ 12.5 of the longitudinal integral length scale of the turbulence to the laminar wave thickness. Accordingly, the Damköhler Da = (L<sub>11</sub>S<sub>L</sub>)=(u'δ<sub>F</sub>) and Karlovitz Ka = δ<sub>F</sub>=(S<sub>L</sub>τ<sub>η</sub>) numbers were varied from 0.01 to 24.7 and from 0.36 to 587, respectively. Here, τ is the Kolmogorov time scale. The obtained DNS data show that, at sufficiently low Da, the fully developed ratio of U<sup>s</sup> <sub>T</sub>/u' is mainly controlled by Da and scales as p Da. However, such a scaling should not be extrapolated to high Da. The higher Da (or the lower Ka), the less pronounced dependence of U<sup>s</sup> <sub>T</sub>/u' on a ratio of L<sub>11</sub>/δ<sub>F</sub>. Moreover, scaling laws U<sub>T</sub> α u'αS<sup>1-α</sup> <sub>L</sub>(L<sub>11</sub>=δ<sub>F</sub>)<sup>β</sup> are substantially different for developing U<sup>t</sup> <sub>T</sub> and fully developed U<sup>s</sup> <sub>T</sub> , i.e., the scaling exponents α and, especially, β depend on the wave-development time. Furthermore, α and, especially, depend on a method used to evaluate the developing U<sup>t</sup> <sub>T</sub> . Such effects can contribute to significant scatter of expressions for U<sub>T</sub> or S<sub>T</sub> as a function of (u', S<sub>L</sub>, L<sub>11</sub>, δ<sub>F</sub>), obtained by parameterizing various experimental databases.</p>}}, author = {{Yu, Rixin and Lipatnikov, Andrei N.}}, issn = {{1070-6631}}, language = {{eng}}, month = {{06}}, number = {{6}}, publisher = {{American Institute of Physics (AIP)}}, series = {{Physics of Fluids}}, title = {{DNS study of dependence of bulk consumption velocity in a constant-density reacting flow on turbulence and mixture characteristics}}, url = {{http://dx.doi.org/10.1063/1.4990836}}, doi = {{10.1063/1.4990836}}, volume = {{29}}, year = {{2017}}, }