Active control of suddenly expanded flows from overexpanded nozzles
An experimental investigation was carried out to study the effectiveness of micro-jets to control base pressure in suddenly expanded axi-symmetric ducts. Four micro-jets of 1 mm orifice diameter located at 90$^\circ$ interval along a pitch circle diameter of 1.3 times the nozzle exit diameter...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Walter de Gruyter
2002
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| Subjects: | |
| Online Access: | http://irep.iium.edu.my/46690/ http://irep.iium.edu.my/46690/1/khan_s_a_-_2002_-_active_control_of_suddenly_expanded_flows_from_overexpanded_nozzles.pdf |
| _version_ | 1848783011897671680 |
|---|---|
| author | Khan, Sher Rathakrishnan, E. |
| author_facet | Khan, Sher Rathakrishnan, E. |
| author_sort | Khan, Sher |
| building | IIUM Repository |
| collection | Online Access |
| description | An experimental investigation was carried out to study the
effectiveness of micro-jets to control base pressure in suddenly
expanded axi-symmetric ducts. Four micro-jets of 1 mm orifice diameter
located at 90$^\circ$ interval along a pitch circle diameter of 1.3
times the nozzle exit diameter in the base region was
employed as active controls. The Mach numbers of the suddenly
expanded flows were studies 2.0, 2.5 and 3.0. The jets were expanded
suddenly
into an axi-symmetric tube with cross-sectional area 2.56, 3.24, 4.84,
and 6.25 times that of nozzle exit diameter. The length-to-diameter
ratio of the sudden expansion tube was varied from 10 to 1. The jets
were operated at an over expansion level of Pe/Pa = 0.277.
The wall pressure distribution in the suddenly enlarged duct was also
measured. It is found that the micro-jets can serve as active
controllers for
base pressure. Also, the wall pressure distribution is not adversely
influenced by the micro-jets. From the present investigation it is
evident that for a given Mach number and nozzle pressure ratio one can
identify the enlargement length to diameter ratio which will result
in maximum increase/decrease of base pressure. |
| first_indexed | 2025-11-14T16:14:34Z |
| format | Article |
| id | iium-46690 |
| institution | International Islamic University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T16:14:34Z |
| publishDate | 2002 |
| publisher | Walter de Gruyter |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | iium-466902016-07-14T23:48:00Z http://irep.iium.edu.my/46690/ Active control of suddenly expanded flows from overexpanded nozzles Khan, Sher Rathakrishnan, E. TL Motor vehicles. Aeronautics. Astronautics An experimental investigation was carried out to study the effectiveness of micro-jets to control base pressure in suddenly expanded axi-symmetric ducts. Four micro-jets of 1 mm orifice diameter located at 90$^\circ$ interval along a pitch circle diameter of 1.3 times the nozzle exit diameter in the base region was employed as active controls. The Mach numbers of the suddenly expanded flows were studies 2.0, 2.5 and 3.0. The jets were expanded suddenly into an axi-symmetric tube with cross-sectional area 2.56, 3.24, 4.84, and 6.25 times that of nozzle exit diameter. The length-to-diameter ratio of the sudden expansion tube was varied from 10 to 1. The jets were operated at an over expansion level of Pe/Pa = 0.277. The wall pressure distribution in the suddenly enlarged duct was also measured. It is found that the micro-jets can serve as active controllers for base pressure. Also, the wall pressure distribution is not adversely influenced by the micro-jets. From the present investigation it is evident that for a given Mach number and nozzle pressure ratio one can identify the enlargement length to diameter ratio which will result in maximum increase/decrease of base pressure. Walter de Gruyter 2002 Article PeerReviewed application/pdf en http://irep.iium.edu.my/46690/1/khan_s_a_-_2002_-_active_control_of_suddenly_expanded_flows_from_overexpanded_nozzles.pdf Khan, Sher and Rathakrishnan, E. (2002) Active control of suddenly expanded flows from overexpanded nozzles. International Journal of Turbo & Jet-Engines, 19 (1-2). pp. 119-126. ISSN 0334-0082 E-ISSN 2191-0332 http://www.degruyter.com/view/j/tjj.2002.19.1-2/tjj.2002.19.1-2.119/tjj.2002.19.1-2.119.xml 10.1515/TJJ.2002.19.1-2.119 |
| spellingShingle | TL Motor vehicles. Aeronautics. Astronautics Khan, Sher Rathakrishnan, E. Active control of suddenly expanded flows from overexpanded nozzles |
| title | Active control of suddenly expanded flows from overexpanded nozzles |
| title_full | Active control of suddenly expanded flows from overexpanded nozzles |
| title_fullStr | Active control of suddenly expanded flows from overexpanded nozzles |
| title_full_unstemmed | Active control of suddenly expanded flows from overexpanded nozzles |
| title_short | Active control of suddenly expanded flows from overexpanded nozzles |
| title_sort | active control of suddenly expanded flows from overexpanded nozzles |
| topic | TL Motor vehicles. Aeronautics. Astronautics |
| url | http://irep.iium.edu.my/46690/ http://irep.iium.edu.my/46690/ http://irep.iium.edu.my/46690/ http://irep.iium.edu.my/46690/1/khan_s_a_-_2002_-_active_control_of_suddenly_expanded_flows_from_overexpanded_nozzles.pdf |