Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body

This investigation presents the outcome of the tests conducted to control the base flows at supersonic Mach numbers. Also the efficiency of the flow controllers to govern the pressure in the base region in a rapidly expanded duct has been exercised. Four tiny jets of 1mm diameter are positioned at 9...

Full description

Bibliographic Details
Main Authors:	Bashir, Musavir, Khan, Sher Afghan
Format:	Article
Language:	English
Published:	Institute of Institutional Industrial Research 2017
Subjects:	TJ751 Miscellaneous motors and engines. Including gas, gasoline, diesel
Online Access:	http://irep.iium.edu.my/61844/ http://irep.iium.edu.my/61844/ http://irep.iium.edu.my/61844/1/Paper6-IJRRA-04-04-16.pdf

id	iium-61844
recordtype	eprints
spelling	iium-618442018-02-05T07:29:08Z http://irep.iium.edu.my/61844/ Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body Bashir, Musavir Khan, Sher Afghan TJ751 Miscellaneous motors and engines. Including gas, gasoline, diesel This investigation presents the outcome of the tests conducted to control the base flows at supersonic Mach numbers. Also the efficiency of the flow controllers to govern the pressure in the base region in a rapidly expanded duct has been exercised. Four tiny jets of 1mm diameter are positioned at 90 intervals at a distance of 6.5 mm from the central axis of the main jet. The inertia levels of the abruptly expanded flows are 1.25, 1.3, 1.48, 1.6, 1.8, 2.0, 2.5 and 3.0. These jets are connected by an axi-symmetric circular brass tube whose cross-sectional area was 2.56, 3.24, 4.84 and 6.25 respectively. The L/D ratio of the enlarged duct was varied from 10 to 1 and NPR was varied from 3 to 11. However, the results presented were for Low Length to Diameter ratio, equal to 4. It was found that when the flow was discharged to the ducts of the given area ratios, it remained attached with the duct wall for all the inertia levels and the NPRs tested in the present case. It was found that the expansion level plays a significant role to decide the pressure at the base and its control efficacy. Whenever, the flow is over expanded, an oblique shock is formed at the nozzle lip, which in turn leads to enhancement of the pressure in the base region. The formation of the shock waves, reflection and recombination continued till the pressure becomes atmospheric. It was observed that the flow remains attached even for low length-to-diameter ratio, equal to 4. No adverse effect of back pressure was observed during the test. It was found that the micro jets can serve as controllers for the base pressure. Institute of Institutional Industrial Research 2017-12 Article PeerReviewed application/pdf en http://irep.iium.edu.my/61844/1/Paper6-IJRRA-04-04-16.pdf Bashir, Musavir and Khan, Sher Afghan (2017) Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body. International Journal of Recent Research Aspects, 4 (4). pp. 59-63. ISSN 2349-7688 https://www.ijrra.net/Vol4issue4/IJRRA-04-04-16.pdf
repository_type	Digital Repository
institution_category	Local University
institution	International Islamic University Malaysia
building	IIUM Repository
collection	Online Access
language	English
topic	TJ751 Miscellaneous motors and engines. Including gas, gasoline, diesel
spellingShingle	TJ751 Miscellaneous motors and engines. Including gas, gasoline, diesel Bashir, Musavir Khan, Sher Afghan Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body
description	This investigation presents the outcome of the tests conducted to control the base flows at supersonic Mach numbers. Also the efficiency of the flow controllers to govern the pressure in the base region in a rapidly expanded duct has been exercised. Four tiny jets of 1mm diameter are positioned at 90 intervals at a distance of 6.5 mm from the central axis of the main jet. The inertia levels of the abruptly expanded flows are 1.25, 1.3, 1.48, 1.6, 1.8, 2.0, 2.5 and 3.0. These jets are connected by an axi-symmetric circular brass tube whose cross-sectional area was 2.56, 3.24, 4.84 and 6.25 respectively. The L/D ratio of the enlarged duct was varied from 10 to 1 and NPR was varied from 3 to 11. However, the results presented were for Low Length to Diameter ratio, equal to 4. It was found that when the flow was discharged to the ducts of the given area ratios, it remained attached with the duct wall for all the inertia levels and the NPRs tested in the present case. It was found that the expansion level plays a significant role to decide the pressure at the base and its control efficacy. Whenever, the flow is over expanded, an oblique shock is formed at the nozzle lip, which in turn leads to enhancement of the pressure in the base region. The formation of the shock waves, reflection and recombination continued till the pressure becomes atmospheric. It was observed that the flow remains attached even for low length-to-diameter ratio, equal to 4. No adverse effect of back pressure was observed during the test. It was found that the micro jets can serve as controllers for the base pressure.
format	Article
author	Bashir, Musavir Khan, Sher Afghan
author_facet	Bashir, Musavir Khan, Sher Afghan
author_sort	Bashir, Musavir
title	Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body
title_short	Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body
title_full	Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body
title_fullStr	Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body
title_full_unstemmed	Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body
title_sort	investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body
publisher	Institute of Institutional Industrial Research
publishDate	2017
url	http://irep.iium.edu.my/61844/ http://irep.iium.edu.my/61844/ http://irep.iium.edu.my/61844/1/Paper6-IJRRA-04-04-16.pdf
first_indexed	2023-09-18T21:27:43Z
last_indexed	2023-09-18T21:27:43Z
_version_	1777412304002875392

Investigation on the prominence of abrupt expansion on the base pressure of an axi-symmetric body

Similar Items