Experimental study of suddenly expanded flow from correctly expanded nozzles

This paper presents the results of the experimental investigation conducted at supersonic Mach numbers through converging–diverging nozzles. The experiments were conducted for correctly expanded cases and, for length-to-diameter ratio of 10 to 1. The area ratios were 1.6, 1.8, 2.2, and 6.25. The r...

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Main Authors: Khan, Sher Afghan, G M, Fharukh Ahmed
Format: Conference or Workshop Item
Language:English
Published: Department of Mechanical Engineering Saveetha School of Engineering Saveetha University 2016
Subjects:
Online Access:http://irep.iium.edu.my/51129/
http://irep.iium.edu.my/51129/
http://irep.iium.edu.my/51129/4/51129.pdf
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recordtype eprints
spelling iium-511292017-01-19T01:45:40Z http://irep.iium.edu.my/51129/ Experimental study of suddenly expanded flow from correctly expanded nozzles Khan, Sher Afghan G M, Fharukh Ahmed TL780 Rockets TL787 Astronautics This paper presents the results of the experimental investigation conducted at supersonic Mach numbers through converging–diverging nozzles. The experiments were conducted for correctly expanded cases and, for length-to-diameter ratio of 10 to 1. The area ratios were 1.6, 1.8, 2.2, and 6.25. The results presented are only for correctly expanded jets. From the results it is found that at lower Mach numbers and area ratios the efficacy of the control in the form of micro jets is only marginal and the control results in increase of base pressure for all the Mach number for the first two lower area ratios namely 2.56 and 3.24, it is also observed that the magnitude is getting enhanced considerably from Mach 1.6 and beyond, but for the larger area ratios namely 4.84 and 6.25 of the present study the control results in decrease of base pressure for Mach numbers in the range 1.6, 1.8, and 2.0. When we analyzed and plotted the wall pressure distribution in the enlarged duct the flow remains unperturbed and attached with the suddenly expanded duct for both with and without control cases. For Mach 1.48 the flow field in the duct becomes oscillatory which; indicates that the flow in the duct is dominated by the waves and when the active control is employed suppresses the noise, and this peculiar phenomenon happens only for this Mach number. However, for Mach 1.8 and 2.0 the flow structure in the duct remained oscillatory for the entire region of the duct, and for rest of the Mach numbers it remained same even when the control in the form of micro jets are activated. Hence, it can be stated that the control with the micro jets does influence the flow in the duct wall adversely except at Mach 1.48. Department of Mechanical Engineering Saveetha School of Engineering Saveetha University 2016-04 Conference or Workshop Item NonPeerReviewed application/pdf en http://irep.iium.edu.my/51129/4/51129.pdf Khan, Sher Afghan and G M, Fharukh Ahmed (2016) Experimental study of suddenly expanded flow from correctly expanded nozzles. In: 2nd International Conference on Design, Analysis, Manufacturing & Simulation, 7th-8th April 2016, Chennai, India. http://www.icdams2016.com/#
repository_type Digital Repository
institution_category Local University
institution International Islamic University Malaysia
building IIUM Repository
collection Online Access
language English
topic TL780 Rockets
TL787 Astronautics
spellingShingle TL780 Rockets
TL787 Astronautics
Khan, Sher Afghan
G M, Fharukh Ahmed
Experimental study of suddenly expanded flow from correctly expanded nozzles
description This paper presents the results of the experimental investigation conducted at supersonic Mach numbers through converging–diverging nozzles. The experiments were conducted for correctly expanded cases and, for length-to-diameter ratio of 10 to 1. The area ratios were 1.6, 1.8, 2.2, and 6.25. The results presented are only for correctly expanded jets. From the results it is found that at lower Mach numbers and area ratios the efficacy of the control in the form of micro jets is only marginal and the control results in increase of base pressure for all the Mach number for the first two lower area ratios namely 2.56 and 3.24, it is also observed that the magnitude is getting enhanced considerably from Mach 1.6 and beyond, but for the larger area ratios namely 4.84 and 6.25 of the present study the control results in decrease of base pressure for Mach numbers in the range 1.6, 1.8, and 2.0. When we analyzed and plotted the wall pressure distribution in the enlarged duct the flow remains unperturbed and attached with the suddenly expanded duct for both with and without control cases. For Mach 1.48 the flow field in the duct becomes oscillatory which; indicates that the flow in the duct is dominated by the waves and when the active control is employed suppresses the noise, and this peculiar phenomenon happens only for this Mach number. However, for Mach 1.8 and 2.0 the flow structure in the duct remained oscillatory for the entire region of the duct, and for rest of the Mach numbers it remained same even when the control in the form of micro jets are activated. Hence, it can be stated that the control with the micro jets does influence the flow in the duct wall adversely except at Mach 1.48.
format Conference or Workshop Item
author Khan, Sher Afghan
G M, Fharukh Ahmed
author_facet Khan, Sher Afghan
G M, Fharukh Ahmed
author_sort Khan, Sher Afghan
title Experimental study of suddenly expanded flow from correctly expanded nozzles
title_short Experimental study of suddenly expanded flow from correctly expanded nozzles
title_full Experimental study of suddenly expanded flow from correctly expanded nozzles
title_fullStr Experimental study of suddenly expanded flow from correctly expanded nozzles
title_full_unstemmed Experimental study of suddenly expanded flow from correctly expanded nozzles
title_sort experimental study of suddenly expanded flow from correctly expanded nozzles
publisher Department of Mechanical Engineering Saveetha School of Engineering Saveetha University
publishDate 2016
url http://irep.iium.edu.my/51129/
http://irep.iium.edu.my/51129/
http://irep.iium.edu.my/51129/4/51129.pdf
first_indexed 2023-09-18T21:12:21Z
last_indexed 2023-09-18T21:12:21Z
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