Numerical Study of a Self-preserving Axisymmetric Turbulent Jet
This paper examines computational modelling of a self-preserving axisymmetric turbulent jet, using a realizable second-moment closure with variable coefficients. The effect of omitting small second order terms in the equations of motion on the final result is investigated. To isolate the contributio...
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| Format: | Article |
| Language: | English |
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Elsevier
2003-01-01
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| Series: | Journal of King Saud University: Engineering Sciences |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S1018363918307852 |
| _version_ | 1811198245836161024 |
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| author | Ali A. Seif |
| author_facet | Ali A. Seif |
| author_sort | Ali A. Seif |
| collection | DOAJ |
| description | This paper examines computational modelling of a self-preserving axisymmetric turbulent jet, using a realizable second-moment closure with variable coefficients. The effect of omitting small second order terms in the equations of motion on the final result is investigated. To isolate the contributions of individual groups of small terms, four similarity solutions were obtained. The results show that omission of any of these terms is seen to affect the spreading and decay rates of the jet as well as the turbulent profiles. The combined effect of omitting all of the small terms is found to be relatively large near the axis of symmetry, in particular, in the profiles of the third moments. Now, since the gradients of third moments determine turbulent diffusion of turbulent kinetic energy, retaining these terms becomes a necessity for a more accurate prediction of the jet. Inclusion of all of the individual groups of small terms that hitherto had been omitted in thin shear-layer calculations produces significant improvement in the results in comparison with experimental data. Keywords: Jets, Turbulence modelling, Similarity solution |
| first_indexed | 2024-04-12T01:27:37Z |
| format | Article |
| id | doaj.art-b585e48d315f457c816b511374603237 |
| institution | Directory Open Access Journal |
| issn | 1018-3639 |
| language | English |
| last_indexed | 2024-04-12T01:27:37Z |
| publishDate | 2003-01-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of King Saud University: Engineering Sciences |
| spelling | doaj.art-b585e48d315f457c816b5113746032372022-12-22T03:53:34ZengElsevierJournal of King Saud University: Engineering Sciences1018-36392003-01-01161159177Numerical Study of a Self-preserving Axisymmetric Turbulent JetAli A. Seif0Department of Mechanical Engineering, King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia, e-mail: alseif@ksu.edu.saThis paper examines computational modelling of a self-preserving axisymmetric turbulent jet, using a realizable second-moment closure with variable coefficients. The effect of omitting small second order terms in the equations of motion on the final result is investigated. To isolate the contributions of individual groups of small terms, four similarity solutions were obtained. The results show that omission of any of these terms is seen to affect the spreading and decay rates of the jet as well as the turbulent profiles. The combined effect of omitting all of the small terms is found to be relatively large near the axis of symmetry, in particular, in the profiles of the third moments. Now, since the gradients of third moments determine turbulent diffusion of turbulent kinetic energy, retaining these terms becomes a necessity for a more accurate prediction of the jet. Inclusion of all of the individual groups of small terms that hitherto had been omitted in thin shear-layer calculations produces significant improvement in the results in comparison with experimental data. Keywords: Jets, Turbulence modelling, Similarity solutionhttp://www.sciencedirect.com/science/article/pii/S1018363918307852 |
| spellingShingle | Ali A. Seif Numerical Study of a Self-preserving Axisymmetric Turbulent Jet Journal of King Saud University: Engineering Sciences |
| title | Numerical Study of a Self-preserving Axisymmetric Turbulent Jet |
| title_full | Numerical Study of a Self-preserving Axisymmetric Turbulent Jet |
| title_fullStr | Numerical Study of a Self-preserving Axisymmetric Turbulent Jet |
| title_full_unstemmed | Numerical Study of a Self-preserving Axisymmetric Turbulent Jet |
| title_short | Numerical Study of a Self-preserving Axisymmetric Turbulent Jet |
| title_sort | numerical study of a self preserving axisymmetric turbulent jet |
| url | http://www.sciencedirect.com/science/article/pii/S1018363918307852 |
| work_keys_str_mv | AT aliaseif numericalstudyofaselfpreservingaxisymmetricturbulentjet |