Phase and Time-Resolved Measurements of Unsteady Heat Transfer and Pressure in a Full-Stage Rotating Turbine

1990 ◽  
Vol 112 (3) ◽  
pp. 531-538 ◽  
Author(s):  
M. G. Dunn
Keyword(s):  
Heat Flux ◽  
Static Pressure ◽  
Pressure Ratio ◽  
Rotor Blades ◽  
Design Flow ◽  
Design Stage ◽  
Unsteady Heat Transfer ◽  
Time Resolved ◽  
Time Histories ◽  
Flux Measurements

This paper presents detailed phase-resolved heat-flux data obtained on rotor blades and a comparison of simultaneously obtained time-resolved heat-flux and static pressure data obtained on the stationary shroud of a Garrett TFE 731-2 HP full-stage rotating turbine. A shock tube is used to generate a short-duration source of heated and pressurized air and platinum thin-film gages are used to obtain heat-flux measurements. Blade results are presented at several selected blade locations. Shroud surface pressure and heat-flux time histories are presented for comparable locations relative to the blade position. For these measurements, the turbine was operating at the design flow function, the design stage pressure ratio, and at 100 percent corrected speed.

Phase and Time-Resolved Measurements of Unsteady Heat Transfer and Pressure in a Full-Stage Rotating Turbine

1989 ◽  
Author(s):  
M. G. Dunn
Keyword(s):  
Heat Flux ◽  
Static Pressure ◽  
Pressure Ratio ◽  
Rotor Blades ◽  
Design Flow ◽  
Design Stage ◽  
Unsteady Heat Transfer ◽  
Time Resolved ◽  
Time Histories ◽  
Flux Measurements

This paper presents detailed phase-resolved heat-flux data obtained on rotor blades and a comparison of simultaneously obtained time-resolved heat-flux and static pressure data obtained on the stationary shroud of a Garrett TFE 731-2 HP full-stage rotating turbine. A shock tube is used to generate a short-duration source of heated and pressurized air and platinum thin-film gages are used to obtain heat-flux measurements. Blade results are presented at several selected blade locations. Shroud surface pressure and heat-flux time histories are presented for comparable locations relative to the blade position. For these measurements, the turbine was operating at the design flow function, the design stage pressure ratio, and at 100% corrected speed.

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.

Phase-Resolved Heat-Flux Measurements on the Blade of a Full-Scale Rotating Turbine

1989 ◽  
Vol 111 (1) ◽  
pp. 8-19 ◽  
Author(s):  
M. G. Dunn ◽  
P. J. Seymour ◽  
S. H. Woodward ◽  
W. K. George ◽  
R. E. Chupp
Keyword(s):  
Heat Flux ◽  
Flux Distribution ◽  
Design Flow ◽  
Heat Flux Distribution ◽  
Time Resolved ◽  
Pressure Surface ◽  
Flux Data ◽  
Heated Air ◽  
Cutting Frequency ◽  
Flux Measurements

This paper presents detailed phase-resolved heat-flux data obtained on the blade of a Teledyne 702 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. Results are presented along the midspan at several locations on the blade suction and pressure surfaces from the stagnation point to near the trailing edge. For these measurements, the turbine was operating at the design flow function and at 100 percent corrected speed. Results are presented for the design vane/blade spacing (0.19 Cs) and at a wide spacing (0.50 Cs). Data are also presented illustrating the phase-resolved blade heat-flux distribution with upstream cold gas injection from discrete holes on the vane surface. The results illustrate that several successive passages can be superimposed upon each other and that a heat-flux pattern can be determined within the passage. A Fourier analysis of the heat-flux record reveals contributions from the fundamental and first harmonic of the passage cutting frequency. Time-resolved surface pressure data obtained on the blade pressure surface are compared with heat-flux data.

Time-Resolved Heat Transfer Measurements on the Tip Wall of a Ribbed Channel Using a Novel Heat Flux Sensor: Part I — Sensor and Benchmarks

2006 ◽  
Author(s):  
Tim Roediger ◽  
Helmut Knauss ◽  
Uwe Gaisbauer ◽  
Ewald Kraemer ◽  
Sean Jenkins ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Turbine Blades ◽  
Temperature Fields ◽  
Heat Flux Sensor ◽  
Internal Cooling ◽  
Time Resolved ◽  
Flux Measurements ◽  
Working Principle ◽  
Flux Sensor

A novel heat flux sensor was tested which allows for time-resolved heat flux measurements in internal ribbed channels related to the study of passages in gas turbine blades. The working principle of the Atomic Layer Thermopile (ALTP) sensor is based on a thermoelectric field created by a temperature gradient over an YBCO crystal (the transverse Seebeck effect). The sensors very fast frequency response allows for highly time-resolved heat flux measurements up to the 1 MHz range. This paper explains the design and working principle of the sensor, as well as the benchmarking of the sensor for several flow conditions. For internal cooling passages, this novel sensor allows for highly accurate, time-resolved measurements of heat transfer coefficients, leading to a greater understanding of the influence of fluctuations in temperature fields.

The Experimental Study of Matching Between Centrifugal Compressor Impeller and Diffuser

1999 ◽  
Vol 121 (1) ◽  
pp. 113-118 ◽  
Author(s):  
H. Tamaki ◽  
H. Nakao ◽  
M. Saito
Keyword(s):  
Flow Rate ◽  
Centrifugal Compressor ◽  
Static Pressure ◽  
Pressure Ratio ◽  
Design Flow ◽  
Negative Slope ◽  
Compressor Stage ◽  
Rate Analysis ◽  
System Pressure ◽  
Compressor Impeller

The centrifugal compressor for a marine use turbocharger with its design pressure ratio of 3.2 was tested with a vaneless diffuser and various vaned diffusers. Vaned diffusers were chosen to cover impeller operating range as broad as possible. The analysis of the static pressure ratio in the impeller and the diffusing system, consisting of the diffuser and scroll, showed that there were four possible combinations of characteristics of impeller pressure ratio and diffusing system pressure ratio, The flow rate, QP, where the impeller achieved maximum static pressure ratio, was surge flow rate of the centrifugal compressor determined by the critical flow rate. In order to operate the compressor at a rate lower than QP, the diffusing system, whose pressure recovery factor was steep negative slope near QP, was needed. When the diffuser throat area was less than a certain value, the compressor efficiency deteriorated; however, the compressor stage pressure ratio was almost constant. In this study, by reducing the diffuser throat area, the compressor could be operated at a flow rate less than 40 percent of its design flow rate. Analysis of the pressure ratio in the impeller and diffusing systems at design and off-design speeds showed that the irregularities in surge line occurred when the component that controlled the negative slope on the compressor stage pressure ratio changed.

Time-Averaged Heat Flux for a Recessed Tip, Lip, and Platform of a Transonic Turbine Blade

2000 ◽  
Author(s):  
M. G. Dunn ◽  
C. W. Haldeman
Keyword(s):  
Heat Flux ◽  
Pressure Ratio ◽  
Design Flow ◽  
Turbine Stage ◽  
Suction Surface ◽  
Surface Measurements ◽  
Blade Tip ◽  
Flux Level ◽  
Transonic Turbine ◽  
Exit Mach Number

The results of an experimental research program determining the blade platform heat-flux level and the influence of blade tip recess on the tip region heat transfer for a full-scale rotating turbine stage at transonic vane exit conditions are described. The turbine used for these measurements was the Allison VBI stage operating in the closed vane position (vane exit Mach number _ 1.1). The stage was operated at the design flow function, total to static pressure ratio, and corrected speed. Measurements were obtained at several locations on the platform and in the blade tip region. The tip region consists of the bottom of the recess, the lip region (on both the pressure and suction surface sides of the recess), and the 90% span location on the blade suction surface. Measurements were obtained for three vane/blade spacings; 20%, 40%, and 60% of vane axial chord and for a single value of the tip gap (the distance between the top of the lip and the stationary shroud) equal to 0.0012-m (0.046-in) or 2.27% of blade height.

Time-Averaged Heat Flux for a Recessed Tip, Lip, and Platform of a Transonic Turbine Blade

2000 ◽  
Vol 122 (4) ◽  
pp. 692-698 ◽  
Author(s):  
M. G. Dunn ◽  
C. W. Haldeman
Keyword(s):  
Heat Flux ◽  
Pressure Ratio ◽  
Design Flow ◽  
Turbine Stage ◽  
Suction Surface ◽  
Surface Measurements ◽  
Blade Tip ◽  
Flux Level ◽  
Transonic Turbine ◽  
Exit Mach Number

The results of an experimental research program determining the blade platform heat-flux level and the influence of blade tip recess on the tip region heat transfer for a full-scale rotating turbine stage at transonic vane exit conditions are described. The turbine used for these measurements was the Allison VBI stage operating in the closed vane position (vane exit Mach number≈1.1). The stage was operated at the design flow function, total to static pressure ratio, and corrected speed. Measurements were obtained at several locations on the platform and in the blade tip region. The tip region consists of the bottom of the recess, the lip region (on both the pressure and suction surface sides of the recess), and the 90 percent span location on the blade suction surface. Measurements were obtained for three vane/blade spacings; 20, 40, and 60 percent of vane axial chord and for a single value of the tip gap (the distance between the top of the lip and the stationary shroud) equal to 0.0012 m (0.046 in) or 2.27 percent of blade height. [S0889-504X(00)00604-8]

Investigation of Unsteady Flow Through a Transonic Turbine Stage: Data/Prediction Comparison for Time-Averaged and Phase-Resolved Pressure Data

1992 ◽  
Vol 114 (1) ◽  
pp. 91-99 ◽  
Author(s):  
M. G. Dunn ◽  
W. A. Bennett ◽  
R. A. Delaney ◽  
K. V. Rao
Keyword(s):  
Pressure Ratio ◽  
Design Flow ◽  
Navier Stokes ◽  
Design Stage ◽  
Pressure Data ◽  
Pressure Transducers ◽  
Data Prediction ◽  
Flow Through ◽  
Transonic Turbine ◽  
Response Pressure

This paper presents time-averaged and phase-resolved measurements of the surface pressure data for the vane and blade of a transonic single-stage research turbine. The data are compared and contrasted with predictions from an unsteady Euler/Navier–Stokes code. The data were taken in a shock-tunnel facility in which the flow was generated with a short-duration source of heated and pressurized air. Surf ace-mounted high-response pressure transducers were used to obtain the pressure measurements. The turbine was operating at the design flow function, the design stage pressure ratio, and 100 percent corrected speed. A matrix of data was obtained at two vane exit conditions and two vane/rotor axial spacings.

Time-Resolved Heat Transfer Measurements on the Tip Wall of a Ribbed Channel Using a Novel Heat Flux Sensor—Part I: Sensor and Benchmarks

2008 ◽  
Vol 130 (1) ◽  
Author(s):  
Tim Roediger ◽  
Helmut Knauss ◽  
Uwe Gaisbauer ◽  
Ewald Kraemer ◽  
Sean Jenkins ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Turbine Blades ◽  
Temperature Fields ◽  
Heat Flux Sensor ◽  
Internal Cooling ◽  
Time Resolved ◽  
Flux Measurements ◽  
Working Principle ◽  
Flux Sensor

A novel heat flux sensor was tested that allows for time-resolved heat flux measurements in internal ribbed channels related to the study of passages in gas turbine blades. The working principle of the atomic layer thermopile (ALTP) sensor is based on a thermoelectric field created by a temperature gradient over an yttrium-barium-copper-oxide (YBCO) crystal (the transverse Seebeck effect). The sensors very fast frequency response allows for highly time-resolved heat flux measurements up to the 1MHz range. This paper explains the design and working principle of the sensor, as well as the benchmarking of the sensor for several flow conditions. For internal cooling passages, this novel sensor allows for highly accurate, time-resolved measurements of heat transfer coefficients, leading to a greater understanding of the influence of fluctuations in temperature fields.

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