Shock Tunnel Operation and Correlation of Boundary Layer Transition on a Cone in Hypervelocity Flow

Abstract

Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. REPORT DATE (DD-MM-YYYY) May 2013 REPORT TYPE Technical Paper DATES COVERED (From -To)May 2013-July 2013 TITLE AND SUBTITLEShock tunnel operation and correlation of boundary layer transition on a cone in hypervelocity flow SPONSOR/MONITOR'S REPORTEdwards AFB CA 93524-7048 NUMBER(S) AFRL-RQ-ED-TP-2013-123 DISTRIBUTION / AVAILABILITY STATEMENTDistribution A: Approved for Public Release; Distribution Unlimited. PA#13304 SUPPLEMENTARY NOTESConference paper for the 29th International Shock Wave Symposium, Madison, WI , 14-19 July 2013. ABSTRACTThe Caltech T5 reflected shock tunnel is used to produce hypervelocity flow over a range of velocities and pressures by varying the test gas and operating parameters of reservoir enthalpy (hres) and reservoir pressure (Pres). One area of research in T5 is the measurement of boundary layer behavior and transition from laminar to turbulent flow on a smooth 5-degree halfangle cone [3,1,11]. To design experiments that involve the measurement or manipulation of instability and transition processes (for example, Jewell et al. [7]), it is important to choose tunnel conditions for which the expected transition location is at least approximately known. In the present paper, we discuss the selection of tunnel operating parameters, the correlation of those parameters with measurements of boundary layer transition, and some observations on the analysis of transition location in terms of local boundary layer properties.

Time-resolved wave packet development in highly cooled hypersonic boundary layers

“…Experiments in this study were conducted in the T5 reflected-shock tunnel at Caltech. The facility design and operation are detailed in Hornung (1992) and Jewell (2014) and described here briefly. A schematic of T5 is shown in figure 1.…”

Effects of Shock-Tube Cleanliness on Slender-Body Hypersonic Instability and Transition Studies at High-Enthalpy

“…A higher coefficient of determination indicates higher repeatability. Jewell et al [26,46] showed that the tunnel parameters h res (reservoir enthalpy) and P res (reservoir pressure) could be used as predictor variables to construct statistically significant linear models of transition Reynolds number Re Tr for both the present data sets and the historical T5 transition data of Germain and Hornung [17] and Adam and Hor-nung [18] for air, CO 2 , and N 2 . In the present work, only air transition data is considered.…”

Displacement of hypersonic boundary layer instability and turbulence through transpiration cooling

“…[4][5][6] In these facilities, researchers commonly utilize the connection of turbulence with aerodynamic friction and hence heat transfer 7 to determine the transition location. 8 Techniques such as infrared thermography, 9,10 thermocouples, 8,11 thin film gauges, 12,13 atomic layer thermopiles (ALTP), 14,15 and temperature sensitive paint 16 are used in the field to infer instability data or laminar-turbulent transition from surface heat flux recordings. However, when a cooling technique is present, surface instruments are evidently subject to coolant and boundary layer gas simultaneously and may therefore be unable to accurately resolve turbulent heating.…”

“…If gas is transpired out of the wall, it will impact transition. 11,24,25 Moreover, the state of the boundary layer also influences the cooling quality. 27 Transpiration cooling runs at risk of advancing transition 25 which was discovered in the 1950s.…”

“…Two more recent studies conducted on cones with gas injection both experimentally inferred transition from surface thermocouple data. 14,31,32 For Jewell et al, 11,31 injection occurred close to the apex, and transition was determined via an intermittency method. 31,33 In contrast, Camillo et al 14 delivered coolant to the boundary layer via a narrow porous injection segment in the direct vicinity of transition on their cone model.…”