Computation of Turbulent Heat Flux with Roughness Induced Transition in High Enthalpy Shock Tunnel HIEST

2016 ◽  
Author(s):  
Tomoaki Ishihara ◽  
Yousuke Ogino ◽  
Naofumi Ohnishi ◽  
Hideyuki Tanno ◽  
Keisuke Sawada
Keyword(s):  
Heat Flux ◽  
Turbulent Heat Flux ◽  
Shock Tunnel ◽  
Turbulent Heat ◽  
High Enthalpy ◽  
High Enthalpy Shock Tunnel

Free-flight measurement technique in the free-piston high-enthalpy shock tunnel

2014 ◽  
Vol 85 (4) ◽  
pp. 045112 ◽  
Author(s):  
H. Tanno ◽  
T. Komuro ◽  
K. Sato ◽  
K. Fujita ◽  
S. J. Laurence
Keyword(s):  
Measurement Technique ◽  
Shock Tunnel ◽  
Free Flight ◽  
Free Piston ◽  
High Enthalpy ◽  
Flight Measurement ◽  
High Enthalpy Shock Tunnel

Testing methodologies in the DLR High Enthalpy Shock Tunnel HEG

1998 ◽  
Author(s):  
W. Beck ◽  
G. Eitelberg ◽  
O. Trinks ◽  
M. Wollenhaupt
Keyword(s):  
Shock Tunnel ◽  
High Enthalpy ◽  
High Enthalpy Shock Tunnel

Fluid Mechanics and Heat Transfer Measurements in Transitional Boundary Layers Conditionally Sampled on Intermittency

1994 ◽  
Vol 116 (3) ◽  
pp. 405-416 ◽  
Author(s):  
J. Kim ◽  
T. W. Simon ◽  
M. Kestoras
Keyword(s):  
Heat Flux ◽  
Plate Boundary ◽  
Turbulent Heat Flux ◽  
Transitional Flow ◽  
Turbulent Heat ◽  
Mean Velocity ◽  
Power Spectral ◽  
Turbulent Characteristics ◽  
Transition Models ◽  
Prandtl Numbers

An experimental investigation of transition on a flat-plate boundary layer was performed. Mean and turbulence quantities, including turbulent heat flux, were sampled according to the intermittency function. Such sampling allows segregation of the signal into two types of behavior—laminarlike and turbulentlike. Results show that during transition these two types of behavior cannot be thought of as separate Blasius and fully turbulent profiles, respectively. Thus, simple transition models in which the desired quantity is assumed to be an average, weighted on intermittency, of the laminar and fully turbulent values may not be entirely successful. Deviation of the flow identified as laminarlike from theoretical laminar behavior is due to a slow recovery after the passage of a turbulent spot, while deviation of the flow identified as turbulentlike from fully turbulent characteristics is possibly due to an incomplete establishment of the fully turbulent power spectral distribution. Measurements were taken for two levels of free-stream disturbance—0.32 and 1.79 percent. Turbulent Prandtl numbers for the transitional flow, computed from measured shear stress, turbulent heat flux, and mean velocity and temperature profiles, were less than unity.

The high enthalpy shock tunnel in Goettingen

1992 ◽  
Author(s):  
G. EITELBERG ◽  
T. MCINTYRE ◽  
W. BECK ◽  
J. LACEY
Keyword(s):  
Shock Tunnel ◽  
High Enthalpy ◽  
High Enthalpy Shock Tunnel

An explicit algebraic Reynolds-stress and scalar-flux model for stably stratified flows

2013 ◽  
Vol 723 ◽  
pp. 91-125 ◽  
Author(s):  
W. M. J. Lazeroms ◽  
G. Brethouwer ◽  
S. Wallin ◽  
A. V. Johansson
Keyword(s):  
Heat Flux ◽  
Kinetic Energy ◽  
Temperature Gradient ◽  
Reynolds Stress ◽  
Turbulent Heat Flux ◽  
Turbulent Heat ◽  
Homogeneous Shear ◽  
Self Consistent ◽  
The Mean ◽  
Homogeneous Shear Flow

AbstractThis work describes the derivation of an algebraic model for the Reynolds stresses and turbulent heat flux in stably stratified turbulent flows, which are mutually coupled for this type of flow. For general two-dimensional mean flows, we present a correct way of expressing the Reynolds-stress anisotropy and the (normalized) turbulent heat flux as tensorial combinations of the mean strain rate, the mean rotation rate, the mean temperature gradient and gravity. A system of linear equations is derived for the coefficients in these expansions, which can easily be solved with computer algebra software for a specific choice of the model constants. The general model is simplified in the case of parallel mean shear flows where the temperature gradient is aligned with gravity. For this case, fully explicit and coupled expressions for the Reynolds-stress tensor and heat-flux vector are given. A self-consistent derivation of this model would, however, require finding a root of a polynomial equation of sixth-order, for which no simple analytical expression exists. Therefore, the nonlinear part of the algebraic equations is modelled through an approximation that is close to the consistent formulation. By using the framework of a$K\text{{\ndash}} \omega $model (where$K$is turbulent kinetic energy and$\omega $an inverse time scale) and, where needed, near-wall corrections, the model is applied to homogeneous shear flow and turbulent channel flow, both with stable stratification. For the case of homogeneous shear flow, the model predicts a critical Richardson number of 0.25 above which the turbulent kinetic energy decays to zero. The channel-flow results agree well with DNS data. Furthermore, the model is shown to be robust and approximately self-consistent. It also fulfils the requirements of realizability.

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