Base pressure behaviour in a suddenly expanded duct at supersonic Mach number regimes using Taguchi design of experiments

• Autorzy: Quadros J. D. , Khan S. A. , Antony A. J.
• Języki publikacji: EN

Abstrakty

EN

Experimental investigations are carried out to study the control of base pressure without and with the use of micro-jets through suddenly expanded axi-symmetric passage in the supersonic regime. Four micro jets having an orifice diameter of 1mm were located at 90˚ intervals. In the base area, active controls jets have been placed on a pitch of a circle diameter that is 1.3 times the exit diameter of the nozzle. The jets were dispensed abruptly into the axi-symmetric tube maintained at a cross-sectional area of 4.84 times the exit nozzle area. The variation of base pressure as a function of flow control parameters namely Mach number, nozzle pressure ratio (NPR) and length to diameter) ratio (L=D) are evaluated experimentally. This study also assesses the impact of flow control variables on base pressure for two cases viz. with control and without control respectively. An L₉ orthogonal array of Taguchi and the analysis of variance were employed to investigate the percentage of contribution of these parameters and their interactions affecting the base pressure. The correlations between the various factors affecting the base pressure were obtained by using multiple linear regression equations. Confirmation tests were conducted in order to test the developed linear regression equations for their practical significance. Both the regression models were found to be significant and reliable with a percentage deviation lying in the range of -6:12% to 10.26% for base pressure without control and -13:92% to 6.58% for base pressure with control. Analysis of variance was also performed in order to determine the statistical significance of each parameter on the total variability of base pressure. The study concluded that Mach number is the most in fluential parameter affecting base pressure followed by NPR and L=D.

Słowa kluczowe

EN

micro-jet; Mach number; nozzle pressure ratio; NPR; length to diameter ratio; Taguchi

PL

mikro-jet; liczba Macha; NPR; współczynnik długości do średnicy; Taguchi

• Wydawca: Wydawnictwo Politechniki Łódzkiej
• Czasopismo: Mechanics and Mechanical Engineering
• Rocznik: 2018
• Tom: Vol. 22, nr 4
• Strony: 1077--1097
• Opis fizyczny: Bibliogr. 13 poz., rys., wykr.

Twórcy

autor

Quadros J. D.

• Department of Mechanical Engineering, Birla Institute of Technology, Off-shore Campus, Ras Al Khaimah-41222, UAE

autor

Khan S. A.

• Department of Mechanical Engineering, International Islamic University Malaysia, Kuala Lampur-50728, Malaysia

autor

Antony A. J.

• Department of Mechanical Engineering, Bearys Institute of Technology, Mangalore-574153, India

Bibliografia

• [1] Wick, R.S.: The effect of boundary layer on sonic flow through an abrupt cross-sectional area change. Journal of Aeronautical Science, 20(10), 675-682, 1953.
• [2] Anderson, J.S., Williams, T.J.: Base pressure and noise produced by the abrupt expansion of air in a cylindrical duct. Journal of Mechanical Engineering Science, 10(3), 262-268, 1968.
• [3] Viswanath, P.R., Patil, S.R.: Effectiveness of Passive Devices for Axisymmetric Base Drag Reduction at Mach 2. Journal of Spacecraft, 27(3), 234-237, 1990.
• [4] Badrinarayanan, M.A.: Experimental investigation of base flows at supersonic speeds. Journal of Royal Aeronautical Society, 65(607), 475-482, 1961.
• [5] Khan, S.A., Rathakrishnan, E.: Active Control of Suddenly Expanded Flows from Over expanded Nozzles. International Journal of Turbo and Jet Engines, 19(1-2), 119-126, 2002.
• [6] Khan, S.A., Rathakrishnan, E.: Control of Suddenly Expanded Flows with Micro Jets. International Journal of Turbo and Jet Engines, 20(1), 63-81, 2003.
• [7] Khan, S.A., Rathakrishnan, E.: Active Control of Suddenly Expanded Flow from Under Expanded Nozzles. International Journal of Turbo and Jet Engines, 21(4), 233-253, 2004.
• [8] Khan, S.A., Rathakrishnan, E.: Control of Suddenly Expanded Flow from Correctly Expanded Nozzles. International Journal of Turbo and Jet Engines, 21(4), 255-278, 2004.
• [9] Khan, S.A., Rathakrishnan, E.: Control of Suddenly Expanded Flow. Aircraft Engineering and Aerospace Technology: International Journal, 78(4), 293-309, 2006.
• [10] Baig, M.A.A., Al-Mufadi, F., Khan, S.A., Rathakrishnan, E.: Control of Base Flows with Micro jets. International Journal of Turbo and Jet Engines, 28(1), 59-69, 2011.
• [11] Cantwell, B.J.: Fundamentals of Compressible Flow. AA210, Department of Aeronautics and Astronautics, Stanford University, California, USA, 1996.
• [12] Rehman S., Khan, S.A.: Control of base pressure with micro-jets: part I. Aircraft Engineering and Aerospace Technology: International Journal, 80(2), 158-164, 2008.
• [13] Rathakrishnan, E., Sreekanth, A.K.: Flow in pipes with sudden enlargement, in: Proceedings of the 14th International Symposium Space Technology and Science, Tokyo, Japan, 491-496, 1984.

Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).