An Investigation in the Variance in Particle Surface Interactions and Their Effects in Gas Turbines

1992 ◽  
Vol 114 (2) ◽  
pp. 235-241 ◽  
Author(s):  
A. Hamed
Keyword(s):  
Gas Turbines ◽  
Laser Doppler Velocimetry ◽  
Particle Trajectory ◽  
Particle Surface ◽  
Axial Flow ◽  
Particle Dynamics ◽  
Surface Interactions ◽  
Distribution Functions ◽  
Particle Velocities ◽  
Trajectory Simulations

This work presents the results of a study conducted to investigate particle surface interaction characteristics and their effects on the particle dynamics and blade erosion in axial flow gas turbines. The particle restitution velocities measured experimentally using Laser Doppler Velocimetry in a special tunnel are analyzed using statistical methods. The resulting distribution functions of the rebounding particle velocities after surface impacts are introduced in the particle trajectory simulations through the turbine blade passages, using a methodology that combines particle dynamics computations in a probabilistic model. The presented results for the simulated ash particle dynamics demonstrate the effect of the experimentally measured variance in the particle restitution characteristics on the particle surface impacts, and the associated blade erosion in an axial flow turbine.

An Investigation in the Variance in Particle Surface Interactions and Their Effects in Gas Turbines

1991 ◽  
Author(s):  
A. Hamed ◽  
W. Tabakoff
Keyword(s):  
Gas Turbines ◽  
Laser Doppler Velocimetry ◽  
Particle Trajectory ◽  
Particle Surface ◽  
Axial Flow ◽  
Particle Dynamics ◽  
Surface Interactions ◽  
Distribution Functions ◽  
Particle Velocities ◽  
Trajectory Simulations

This work presents the results of a study conducted to investigate particle surface interaction characteristics and their effects on the particle dynamics and blade erosion in axial flow gas turbines. The particle restitution velocities measured experimentally using Laser Doppler Velocimetry in a special tunnel are analyzed using statistical methods. The resulting distribution functions of the rebounding particle velocities after surface impacts are introduced in the particle trajectory simulations through the turbine blade passages, using a methodology that combines particle dynamics computations in a probabilistic model. The presented results for the simulated ash particle dynamics demonstrate the effect of the experimentally measured variance in the particle restitution characteristics on the particle surface impacts, and the associated blade erosion in an axial flow turbine.

Effects of Variational Particle Restitution Characteristics on Turbomachinery Erosion

1993 ◽  
Author(s):  
Awatef Hamed ◽  
Timothy P. Kuhn
Keyword(s):  
Gas Turbines ◽  
Laser Doppler Velocimetry ◽  
Particle Trajectory ◽  
Particle Dynamics ◽  
Distribution Functions ◽  
Cumulative Distribution ◽  
Sampling Techniques ◽  
Flow Conditions ◽  
Mean Values ◽  
Particle Velocities

This paper presents the results of an investigation to determine the effects of variational particle rebounding models on surface impacts and blade erosion patterns in gas turbines. The variance in the particle velocities after the surface impacts are modeled based on the experimental measurements using Laser Doppler Velocimetry (LDV) under varying flow conditions. The probabilistic particle trajectory computations simulate the experimental variance in the particle restitution characteristics using cumulative distribution functions and random sampling techniques. The results are presented for the particle dynamics through a gas turbine flow field and are compared to those obtained with deterministic rebound models based on experimental mean values.

Effects of Variational Particle Restitution Characteristics on Turbomachinery Erosion

1995 ◽  
Vol 117 (3) ◽  
pp. 432-440 ◽  
Author(s):  
A. Hamed ◽  
T. P. Kuhn
Keyword(s):  
Gas Turbines ◽  
Laser Doppler Velocimetry ◽  
Particle Trajectory ◽  
Particle Dynamics ◽  
Distribution Functions ◽  
Cumulative Distribution ◽  
Sampling Techniques ◽  
Flow Conditions ◽  
Mean Values ◽  
Particle Velocities

This paper presents the results of an investigation to determine the effects of variational particle rebounding models on surface impacts and blade erosion patterns in gas turbines. The variance in the particle velocities after the surface impacts are modeled based on the experimental measurements using Laser-Doppler Velocimetry (LDV) under varying flow conditions. The probabilistic particle trajectory computations simulate the experimental variance in the particle restitution characteristics using cumulative distribution functions and random sampling techniques. The results are presented for the particle dynamics through a gas turbine flow field and are compared to those obtained with deterministic rebound models based on experimental mean values.

Influence of Secondary Flow on Turbine Erosion

1989 ◽  
Vol 111 (3) ◽  
pp. 310-314 ◽  
Author(s):  
A. Hamed
Keyword(s):  
Secondary Flow ◽  
Gas Turbines ◽  
Trajectory Analysis ◽  
Three Dimensional ◽  
Axial Flow ◽  
Coal Ash ◽  
Particle Dynamics ◽  
Experimental Measurements ◽  
Material Erosion ◽  
Erosion Intensity

This work presents the results of an investigation conducted to study the effect of secondary flow on blade erosion by coal ash particles in axial flow gas turbines. The particle dynamics and their blade impacts are determined from a three-dimensional trajectory analysis within the turbine blade passages. The blade material erosion behavior and the particle rebound characteristics are simulated using empirical equations derived from experimental measurements. The results demonstrate that the secondary flow has a significant influence on the blade erosion intensity and pattern for the typical ash particle size distribution considered in this investigation.

scholarly journals Effect of Particle Size Distribution on Particle Dynamics and Blade Erosion in Axial Flow Turbines

1990 ◽  
Author(s):  
W. Tabakoff ◽  
A. Hamed ◽  
M. Metwally
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Gas Turbines ◽  
Three Dimensional ◽  
Axial Flow ◽  
Coal Ash ◽  
Particle Dynamics ◽  
Material Erosion ◽  
Particles Size Distribution

This work presents the results of an investigation conducted to study the effect of coal ash particles size distribution on the particle dynamics, and the resulting blade erosion in axial flow gas turbines. The particle dynamics and their blade impacts are determined from a three dimensional trajectory analysis within the turbine blade passages. The particle rebound conditions and the blade material erosion characteristics are simulated using empirical equations, derived from experimental measurements. For the typical ash particle size distribution considered in this investigation, the results demonstrate that the size distribution has a significant influence on the blade erosion intensity and pattern.

Effect of Particle Size Distribution on Particle Dynamics and Blade Erosion in Axial Flow Turbines

1991 ◽  
Vol 113 (4) ◽  
pp. 607-615 ◽  
Author(s):  
W. Tabakoff ◽  
A. Hamed ◽  
M. Metwally
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Gas Turbines ◽  
Three Dimensional ◽  
Axial Flow ◽  
Coal Ash ◽  
Particle Dynamics ◽  
Material Erosion ◽  
Effect Of Particle Size

This work presents the results of an investigation conducted to study the effect of coal ash particle size distribution on the particle dynamics, and the resulting blade erosion in axial flow gas turbines. The particle dynamics and their blade impacts are determined from a three-dimensional trajectory analysis within the turbine blade passages. The particle rebound conditions and the blade material erosion characteristics are simulated using empirical equations, derived from experimental measurements. For the typical ash particle size distribution considered in this investigation, the results demonstrate that the size distribution has a significant influence on the blade erosion intensity and pattern.

Performance Estimation of Axial Flow Turbines

1970 ◽  
Vol 185 (1) ◽  
pp. 407-424 ◽  
Author(s):  
H. R. M. Craig ◽  
H. J. A. Cox
Keyword(s):  
Reynolds Number ◽  
Aspect Ratio ◽  
Gas Turbines ◽  
Three Dimensional ◽  
Axial Flow ◽  
Performance Estimation ◽  
Speed Ratio ◽  
Test Results ◽  
Wide Range ◽  
Relevant Variables

A comprehensive method of estimating the performance of axial flow steam and gas turbines is presented, based on analysis of linear cascade tests on blading, on a number of turbine test results, and on air tests of model casings. The validity of the use of such data is briefly considered. Data are presented to allow performance estimation of actual machines over a wide range of Reynolds number, Mach number, aspect ratio and other relevant variables. The use of the method in connection with three-dimensional methods of flow estimation is considered, and data presented showing encouraging agreement between estimates and available test results. Finally ‘carpets’ are presented showing the trends in efficiencies that are attainable in turbines designed over a wide range of loading, axial velocity/blade speed ratio, Reynolds number and aspect ratio.

Sign in / Sign up

Export Citation Format

Share Document