Detection and Transient Dynamics Modeling of Experimental Hypersonic Inlet Unstart

Hutchins, Kelley E.; Akella, Maruthi R.; Clemens, Noel T.; Donbar, Jeffrey M.

doi:10.2514/6.2012-2808

Cited by 12 publications

(4 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The concomitant separation regions, noted to be large, highly three-dimensional and unsteady, correlate with the largest adverse pressure gradients. The results have been employed to detect and model transient dynamics of unstart [142,150].…”

Section: Sbli In Complex Configurationsmentioning

confidence: 99%

Progress in shock wave/boundary layer interactions

Gaitonde

2015

Progress in Aerospace Sciences

521

126

View full text Add to dashboard Cite

Section: Sbli In Complex Configurationsmentioning

confidence: 99%

Progress in shock wave/boundary layer interactions

Gaitonde

2015

Progress in Aerospace Sciences

521

126

View full text Add to dashboard Cite

“…The results have been employed to detect and model transient dynamics of unstart. 140,148 As noted in the motivation, although not a specific focus of interest, SBLI are a major factor, with well recognized impacts, in practical systems such as the HIFiRE-2 and X-51 programs. The HIFiRE-2 23 program, introduced in Fig.2(b), has been especially helpful from the basic research perspective because of the ready availability of groundtest data, key parameters such as flight profile, test conditions and geometric configuration.…”

Section: Sbli In Complex Configurationsmentioning

confidence: 99%

Progress in Shock Wave/Boundary Layer Interactions

Gaitonde

2013

43rd Fluid Dynamics Conference

View full text Add to dashboard Cite

Recent advances in shock wave boundary layer interaction research are reviewed in four areas: i) understanding low frequency unsteadiness, ii) heat transfer prediction capability, iii) phenomena in complex (multi-shock boundary layer) interactions and iv) flow control techniques. Substantial success has been achieved in describing the phenomenology of low frequency unsteadiness, including correlations and coherent structures in the separation bubble, through complementary experimental and numerical studies on nominally 2-D interactions. These observations have been parlayed to propose underlying mechanisms based on oscillation, amplification and upstream boundary layer effects. For heat transfer prediction capability, systematic studies conducted under the auspices of AFOSR and RTO-AVT activities have shown that for axisymmetric laminar situations, heat transfer rates can be measured and in some cases be predicted reasonably accurately even in the presence of high-temperature effects. Efforts have quantified uncertainty of Reynolds averaged turbulence models, and hybrid methods have been developed to at least partially address deficiencies. Progress in complex interactions encompass two of the major phenomena affected by SBLI in scramjet flowpaths: unstart and mode transition from ramjet (dual mode) to scramjet. Control studies have attempted to leverage the better understanding of the fundamental phenomena with passive and active techniques, the latter exploiting the superior properties of newer actuators. Of interest are not only reduction in separation and surface loads, but also the spectral content. Finally, SBLI studies have benefited handsomely from successful ground and flight test campaigns associated with the HIFiRE-1 and HIFiRE-2 campaigns, results from which which are woven into the discussion, as are limitations in current capability and understanding.

show abstract

“…in developing a model of the dynamics of unstart through the use of system identification techniques. [3][4][5] Another aspect of the inlet unstart problem involves research into estimating shock position within the isolator. A large number of studies have been conducted implementing various schemes including summation of pressures, power spectral density change detection algorithms, and other novel approaches.…”

Section: Introductionmentioning

confidence: 99%

Closed-loop Control of Shock Location in Mach 1.8 Direct Connect Wind Tunnel

Ashley

Szmuk

Clemens

et al. 2014

7th AIAA Flow Control Conference

View full text Add to dashboard Cite

This paper presents the design and implementation of a closed-loop control scheme to regulate shock location within a Mach 1.8 wind tunnel isolator test section. As part of the feedback controller, the sensing scheme for shock localization utilizes a set of high frequency Kulite pressure transducers to sample the static pressure at various points along the wind tunnel test section. A geometry-based shock localization algorithm is then executed at 250 Hz to determine the location of the shock in real time. The closed-loop controller generates actuation commands for a motorized flap downstream of the test section every 100 ms toward regulating the shock at the desired position. Several forms of closed-loop implementation are addressed including: (a) simple logic-based controllers; (b) Proportional-Integral (PI) controllers, and (c) Proportional-Derivative (PD) controllers. In addition to using the geometry-based shock localization schemes, the paper also describes the implementation of a novel Kalman-filter-based framework for fusing estimates from other shock localization schemes such as standard deviation and sum-of-squares. It also explores important design criteria that should be considered for satisfactory control performance as a function of pressure transducer spacing, shock localization speed, flapmotor's actuation speed and actuator resolution. Experimental results are presented for various test scenarios such as regulation of the shock location in the presence of stagnation pressure disturbances as well as tracking of a time-varying reference input. Performance and robustness analysis of the control system during these tests is discussed. Further areas of improvement for the closed-loop control system in both hardware and software are discussed along with possible applications. Nomenclature DTR= Dense Transducer Region PD = Proportional-Derivative

show abstract

Detection and Transient Dynamics Modeling of Experimental Hypersonic Inlet Unstart

Cited by 12 publications

References 29 publications

Progress in shock wave/boundary layer interactions

Progress in shock wave/boundary layer interactions

Progress in Shock Wave/Boundary Layer Interactions

Closed-loop Control of Shock Location in Mach 1.8 Direct Connect Wind Tunnel

Contact Info

Product

Resources

About