Numerical Investigation of the Interaction of Counterflowing Jets and Supersonic Capsule Flows

Venkatachari, Balaji Shankar; Ito, Yasushi; Cheng, Gary; Chang, Chau‐Lyan

doi:10.2514/6.2011-4030

Cited by 19 publications

(25 citation statements)

References 23 publications

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“…Long Penetration Mode occurs when the total pressure ratio is relatively small and it is characterized by oscillating detached shockwave and diamond pattern cells as given in Fig 1(a). When the total pressure ratio is beyond a critical value, the unstable flow reverts back into a near stable flow with the structure shown in Fig 1(b) 30 . In contrast to LPM, the bow shock remains close to the blunt body and the jet does not penetrate the bow shock.…”

Section: Fig1 Flow Field Structure Characterization For a Jet Issuinmentioning

confidence: 91%

A novel means of dissipation of shock wave induced heat in a high speed flow

Zheng

Ahmed

2013

43rd Fluid Dynamics Conference

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The present paper proposes a novel means of heat dissipation in high speed flows where shock waves are formed by transferring heat along shock wave without transferring heat to body itself. This may be achieved through controlled oscillation of the shock wave without making it and the flow surrounding it unstable. From an experimental investigation on a 1/30 scale Apollo module using the supersonic wind tunnel at the Aerodynamics Laboratory of the University of New South Wales at Mach 3, counter flow jet injection and deploying into upstream flow behind the detached bow shock wave are formed to examine this concept. Results obtained are very promising and provide clear evidence to support this concept. The findings have the potential of achieving heat reduction with lower energy requirement. A greater understanding of the various interacting flow mechanism and optimization of different design parameters may open up the possibility of incorporating the concept into a viable and cost effective thermal protection systems for high speed vehicles.

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Section: Fig1 Flow Field Structure Characterization For a Jet Issuinmentioning

confidence: 91%

A novel means of dissipation of shock wave induced heat in a high speed flow

Zheng

Ahmed

2013

43rd Fluid Dynamics Conference

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“…Despite the conclusions of Miller and Carlson 22 and Fomin et al, 23 we intended to explore the potential of LPM jets and their application in boom and drag mitigation in a more thorough manner, using computational studies. Our improved understanding of the LPM jets through earlier investigations 9,14 drove this study. In this regard, the authors of this paper had previously conducted a pilot computational study 24 on the use of the LPM of a counterflowing supersonic jet for sonic boom mitigation.…”

Section: Background and Introductionmentioning

confidence: 97%

“…[9][10][11][12][13][14] Two different modes of jet interaction with the oncoming freestream exist, namely the short penetration mode (SPM) and long penetration mode (LPM), pictorially represented in Fig. 1.…”

Section: Background and Introductionmentioning

confidence: 99%

Numerical Study of Counterflowing Jet Effects on Supersonic Slender-Body Configurations

Venkatachari

Mullane

Cheng

et al. 2015

33rd AIAA Applied Aerodynamics Conference

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Previous studies have demonstrated that the use of counterflowing jets can greatly reduce the drag and heat loads on blunt-body geometries, especially when the long penetration mode jet condition can be established. Previously, the authors had done some preliminary numerical studies to determine the ability to establish long penetration mode jets on a typical Mach 1.6 slender configuration, and study its impact on the boom signature. The results indicated that a jet with a longer penetration length was required to achieve any impact on the boom signature of a typical Mach 1.6 slender configuration. This paper focuses on an in-depth parametric study, done using the space-time conservation element solution element Navier-Stokes flow solver, for investigating the effect of various counterflowing jet conditions/configurations on two supersonic slender-body models (cone-cylinder and quartic body of revolution). The study is aimed at gaining a better understanding of the relationship between the shock penetration length and reduction of drag and boom signature for these two supersonic slender-body configurations. Different jet flow rates, Mach numbers, nozzle jet exit diameters and jet-to-base diameter ratios were examined. The results show the characteristics of a short-to-long-to-short penetration-mode pattern with the increase of jet mass flow rates, observed across various counterflowing jet nozzle configurations. Though the optimal shock penetration length for potential boom-signature mitigation is tied to the long penetration mode, it often results in a very unsteady flow and leads to large oscillations of surface pressure and drag. Furthermore, depending on the geometry of the slender body, longer jet penetration did not always result in maximum drag reduction. For the quartic geometry, the maximum drag reduction corresponds well to the longest shock penetration length, while this was not the case for the cone-cylinder-as the geometry was already optimized for drag. Numerical results and assessments obtained from this parametric study along with the recommendation for future implementation of counterflowing jets as a means for drag and noise reduction are detailed in this paper. Nomenclature d j = Jet exit diameter, mm (or inch) d m = Model diameter, mm (or inch) h = distance away from the centerline of the body, cm L = Length, cm L p = Jet penetration length, cm (or inch)

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“…It has already been widely applied in simulations of sound wave propagation [9], aero-acoustics [5,17], steady viscous flows [18], supersonic capsule flows [19], hypersonic viscous flows [20], elastic wave propagation in solids [21], ultra-relativistic Euler equation problems [22], magneto-hydrodynamic flows [10,[23][24][25][26][27], chemical reactive flows [12,16,[28][29][30], multi-material elastic-plastic flows [15], spall fracture phenomena [31] and many electrical engineering problems [32]. However, in the following paper, we will see that the computational accuracy of the CE/SE scheme is not as satisfactory as high order schemes, when applied to certain complex fine fluid structures.…”

Section: Introductionmentioning

confidence: 99%