Determination of heat transfer into a wedge model in a hypersonic flow using temperature-sensitive paint

Heat loads on spacecraft traveling at hypersonic speed are of major interest for their designers. Several tests using temperature-sensitive paints (TSP) have been carried out in long duration shock tunnels to determine these heat loads; generally paint layers were thin, so that certain assumptions could be invoked to enable a good estimate of the thermal parameter ρck (a material property) to be obtained—the value of this parameter is needed to determine heat loads from the TSP. Very few measurements have been carried out in impulse facilities [viz. shock tunnels such as the High Enthalpy Shock Tunnel Göttingen (HEG)], where test times are much shorter. Presented here are TSP temperature measurements and subsequently derived heat loads on a ramp model placed in a hypersonic flow in HEG (specific enthalpy h0 = ~3.3 MJ kg−1, Mach number M = 7.4, temperature T∞ = 277 K, density ρ∞ = 11 g m−3). A number of fluorescence intensity images were acquired, from which, with the help of calibration data, temperature field data on the model surface were determined. From these the heat load into the surface was calculated, using an assumption of a 1D, semi-infinite heat transfer model. ρck for the paint was determined using an insitu calibration with a Medtherm coaxial thermocouple mounted on the model; Medtherm ρck is known. Finally presented are sources of various measurement uncertainties, arising from: (1) estimation of ρck; (2) intensity measurement in the chosen interrogation area; (3) paint time response.

[1]  T. V. Jones,et al.  Heat-transfer measurements in short-duration hypersonic facilities , 1973 .

[2]  S. Laurence,et al.  Fast-response temperature-sensitive-paint measurements on a hypersonic transition cone , 2014 .

[3]  H. Nagai,et al.  Effect of TSP Layer Thickness on Global Heat Transfer Measurement in Hypersonic Flow , 2006 .

[4]  H. Nagai,et al.  Global Heat Flux Measurement Using Temperature-Sensitive Paint in High-Enthalpy Shock Tunnel HIEST , 2017 .

[5]  M. Bruse,et al.  Application of Carbon Nanotubes (CNT) and Temperature-Sensitive Paint (TSP) for the Detection of Boundary Layer Transition , 2014 .

[6]  Tianshu Liu,et al.  Fast Pressure-Sensitive Paint for Flow and Acoustic Diagnostics , 2014 .

[7]  S. Laurence,et al.  Schlieren-based techniques for investigating instability development and transition in a hypersonic boundary layer , 2014 .

[8]  Christian Klein,et al.  Development of Temperature Sensitive Paints in the High Enthalpy Shock Tunnel Göttingen, HEG , 2015 .

[9]  Ulrich Henne,et al.  Application of Temperature and Pressure Sensitive Paints to DLR Hypersonic Facilities: “lessons learned” , 2015 .

[10]  Klaus Hannemann,et al.  Recent Extensions to the High Enthalpy Shock Tunnel Göttingen (HEG , 2008 .

[11]  Di Peng,et al.  Simultaneous PSP and TSP measurements of transient flow in a long-duration hypersonic tunnel , 2016 .

[12]  Ulrich Henne,et al.  Europium 1,3-di(thienyl)propane-1,3-diones with outstanding properties for temperature sensing , 2015 .

[13]  Christian Klein,et al.  Experimental Investigation of the Effect of Forward-facing Steps on Boundary Layer Transition , 2015 .

[14]  U. Henne,et al.  Investigation of three-dimensional dynamic stall on an airfoil using fast-response pressure-sensitive paint , 2014, Experiments in Fluids.

[15]  C. Klein,et al.  Application of pressure-sensitive paint for determination of the pressure field and calculation of the forces and moments of models in a wind tunnel , 2005 .

[16]  Tianshu Liu,et al.  Pressure and Temperature Sensitive Paints , 2004, Experimental Fluid Mechanics.

[17]  K. Hannemann,et al.  Experiments on passive hypersonic boundary layer control using ultrasonically absorptive carbon–carbon material with random microstructure , 2013 .

[18]  Stefan Hein,et al.  Complementary Numerical and Experimental Data Analysis of the ETW Telfona Pathfinder Wing Transition Tests , 2011 .

[19]  Klaus Hannemann,et al.  Investigation of Unsteady/Quasi-Steady Scramjet Behavior using High-Speed Visualization Techniques , 2012 .

[20]  Christian Klein,et al.  Investigation of Reynolds Number Effects in High-Speed TrainWind Tunnel Testing using Temperature-Sensitive Paint , 2013 .

[21]  Christian Klein,et al.  Pressure sensitive paint systems for pressure distribution measurements in wind tunnels and turbomachines , 2000 .

[22]  W. Cook,et al.  Reduction of data from thin-film heat-transfer gages - A concise numerical technique. , 1966 .

[23]  Keisuke Asai,et al.  Global Heat Transfer Measurement in a Hypersonic Shock Tunnel Using Temperature-Sensitive Paint , 2003 .