Demonstrating the Use of Thin Film Gauges for Heat Flux Measurements in ICEs: Measurements on an Inlet Valve in Motored Operation

2016 ◽  
Author(s):  
Thomas De Cuyper ◽  
Sam Bracke ◽  
Jolien Lavens ◽  
Stijn Broekaert ◽  
Kam Chana ◽  
...  
Keyword(s):  
Thin Film ◽  
Heat Flux ◽  
Inlet Valve ◽  
Flux Measurements

Heat-Flux Measurements for the Rotor of a Full-Stage Turbine: Part II—Description of Analysis Technique and Typical Time-Resolved Measurements

1986 ◽  
Vol 108 (1) ◽  
pp. 98-107 ◽  
Author(s):  
M. G. Dunn ◽  
W. K. George ◽  
W. J. Rae ◽  
S. H. Woodward ◽  
J. C. Moller ◽  
...  
Keyword(s):  
Thin Film ◽  
Heat Flux ◽  
Design Flow ◽  
Suction Surface ◽  
Stagnation Region ◽  
Time Resolved ◽  
Analysis Technique ◽  
Typical Time ◽  
Flux Measurements ◽  
Dominant Frequencies

This paper presents a detailed description of an analysis technique and an application of this technique to obtain time-resolved heat flux for the blade of a Garrett TFE 731-2 hp full-stage rotating turbine. A shock tube is used as a short-duration source of heated air and platinum thin-film gages are used to obtain the heat-flux measurements. To obtain the heat-flux values from the thin-film gage temperature histories, a finite-difference procedure has been used to solve the heat equation, with variable thermal properties. The data acquisition and the data analysis procedures are described in detail and then their application is illustrated for three midspan locations on the blade. The selected locations are the geometric stagnation point, 32.7 percent wetted distance on the suction surface, and 85.5 percent wetted distance on the suction surface. For these measurements, the turbine was operating at the design flow function and very near 100 percent corrected speed. The vane–blade axial spacing was consistent with the engine operating configuration. The results demonstrate that the magnitude of the heat-flux fluctuation resulting from the vane–blade interaction is large by comparison with the time-averaged heat flux at all locations investigated. The magnitude of the fluctuation is greatest in the stagnation region and decreases with increasing wetted distance along the surface. A Fourier analysis by FFT of a portion of the heat-flux record illustrates that the dominant frequencies occur at the wake-cutting frequency and its harmonics.

Time-Averaged Heat-Flux Distributions and Comparison With Prediction for the Teledyne 702 HP Turbine Stage

1988 ◽  
Vol 110 (1) ◽  
pp. 51-56 ◽  
Author(s):  
M. G. Dunn ◽  
R. E. Chupp
Keyword(s):  
Thin Film ◽  
Heat Flux ◽  
Shock Tube ◽  
Flat Plate ◽  
Leading Edge ◽  
Turbine Stage ◽  
Heated Air ◽  
Edge Distribution ◽  
Flux Measurements ◽  
Good Agreement

Time-averaged heat-flux distributions are reported for the vane and blade of the Teledyne CAE 702 HP full-stage rotating turbine. A shock tube is used as a short-duration source of heated air to which the turbine is subjected and thin-film gages are used to obtain the heat-flux measurements. The thin-film gages were concentrated on the midspan region from the leading edge to near the trailing edge. The blade contained two contoured inserts wtih gages spaced very close together so that the leading edge distribution could be resolved. The NGV and blade results are compared with predictions obtained using a flat-plate technique, an eddy-diffusing model (STAN 5), and a k–ε model. The results of the comparison between data and prediction suggest that: (a) first, the vane data are bounded by the turbulent flat plate and the fully turbulent STAN 5 prediction. For the vane, the k–ε prediction is in relatively good agreement with the STAN 5 prediction and (b) secondly, the blade data are acceptably predicted by the k–ε prediction on both the pressure and the suction surfaces. The STAN 5 fully turbulent calculation for the blade falls above the data (essentially in agreement with the turbulent flat-plate calculation) and the STAN 5 fully laminar falls substantially below the data. With the exception of the pressure loadings and the geometry, the code inputs used for these predictions were identical to those previously used to predict the Garrett TFE 731-2 HP turbine and the Garrett LART HP turbine.

Time-Averaged and Time-Resolved Heat Flux Measurements on a Turbine Stator Blade Using Two-Layered Thin-Film Gauges

2004 ◽  
Author(s):  
V. Iliopoulou ◽  
R. De´nos ◽  
N. Billiard ◽  
T. Arts
Keyword(s):  
Thin Film ◽  
Heat Flux ◽  
Numerical Algorithm ◽  
Temperature History ◽  
Layered System ◽  
Time Resolved ◽  
Flux Measurements ◽  
Stator Blade ◽  
Original Procedure ◽  
Layered Thin Film

This paper describes the steps undertaken to measure heat flux in a turbine tested in a blowdown windtunnel when using a two-layered thin film gauge array. The sensor consists of a nickel thermo resistor deposited onto a flexible polymide sheet that can be easily bounded on a substrate using double sided adhesive. The assembly constitutes a two-layered system. First, a numerical algorithm is proposed to extract the wall heat flux from the surface temperature history measured by the thin film gauge. It is very flexible and handles multi-layered systems. Then, an original procedure is proposed to determine the thermal properties and the thickness of the different layers. It uses the above numerical algorithm coupled with a minimization routine. The repeatability of the procedure is assessed. Finally, tests are processed according to the proposed method. The results are successfully compared with measurements performed with single-layered thin film gauges.

Time-Averaged and Time-Resolved Heat Flux Measurements on a Turbine Stator Blade Using Two-Layered Thin-Film Gauges

2004 ◽  
Vol 126 (4) ◽  
pp. 570-577 ◽  
Author(s):  
V. Iliopoulou ◽  
R. De´nos ◽  
N. Billiard ◽  
T. Arts
Keyword(s):  
Thin Film ◽  
Heat Flux ◽  
Numerical Algorithm ◽  
Temperature History ◽  
Layered System ◽  
Time Resolved ◽  
Multilayered Systems ◽  
Flux Measurements ◽  
Stator Blade ◽  
Layered Thin Film

This paper describes the steps undertaken to measure heat flux in a turbine tested in a blowdown windtunnel when using a two-layered thin film gauge array. The sensor consists of a nickel thermoresistor deposited onto a flexible polyamide sheet that can be easily bounded on a substrate using double sided adhesive. The assembly constitutes a two-layered system. First, a numerical algorithm is proposed to extract the wall heat flux from the surface temperature history measured by the thin film gauge. It is very flexible and handles multilayered systems. Then, an original procedure is proposed to determine the thermal properties and the thickness of the different layers. It uses the above numerical algorithm coupled with a minimization routine. The repeatability of the procedure is assessed. Finally, tests are processed according to the proposed method. The results are successfully compared with measurements performed with single-layered thin film gauges.

QUANTIFYING ERRORS IN HEAT FLUX MEASUREMENTS USING A VERTICAL SEQUENCE OF THERMOCOUPLE SENSORS

2016 ◽  
Author(s):  
Gabriela Villegas ◽  
◽  
Jerry P. Fairley ◽  
Cary R. Lindsey ◽  
Megan M. Aunan ◽  
...  
Keyword(s):  
Heat Flux ◽  
Flux Measurements

Fast-Response transient heat flux measurements in a plasma wind tunnel

2021 ◽  
Vol 173 ◽  
pp. 121234
Author(s):  
Byrenn Birch ◽  
David Buttsworth ◽  
Stefan Löhle ◽  
Fabian Hufgard
Keyword(s):  
Heat Flux ◽  
Wind Tunnel ◽  
Fast Response ◽  
Flux Measurements ◽  
Transient Heat Flux

An analog period method for gap‐filling of latent heat flux measurements

2021 ◽  
Author(s):  
Lucas Emilio B. Hoeltgebaum ◽  
Nelson Luís Dias ◽  
Marcelo Azevedo Costa
Keyword(s):  
Heat Flux ◽  
Latent Heat ◽  
Latent Heat Flux ◽  
Gap Filling ◽  
Flux Measurements

Hybrid model of thin film boiling: Insights into the unique behavior and ultrahigh heat flux

2021 ◽  
Vol 179 ◽  
pp. 121702
Author(s):  
Lin Chen ◽  
Fengchu Jin ◽  
Jiahua Li ◽  
Yanchao Lv ◽  
Qingyang Wang ◽  
...  
Keyword(s):  
Thin Film ◽  
Heat Flux ◽  
Hybrid Model ◽  
Film Boiling
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