Numerical Investigation of the Effect of Blade Manufacturing Tolerances on Axial Turbine Performance

2022 ◽  
Author(s):  
Munir Elfarra ◽  
Mehmet N. Onel ◽  
Yalin Kaptan ◽  
Mustafa Kaya
Keyword(s):  
Numerical Investigation ◽  
Axial Turbine ◽  
Turbine Performance ◽  
Manufacturing Tolerances

Numerical Simulation on the Flow Control by Mounting Indented Gurney Flaps for a Wind Turbine

2012 ◽  
Vol 512-515 ◽  
pp. 623-627 ◽  
Author(s):  
Wan Li Zhao ◽  
Xiao Lei Zheng
Keyword(s):  
Numerical Simulation ◽  
Wind Turbine ◽  
Numerical Investigation ◽  
Wind Turbines ◽  
Aerodynamic Performance ◽  
Optimal Position ◽  
Gurney Flaps ◽  
Turbine Performance ◽  
Gurney Flap ◽  
Practical Engineering

Numerical investigation of large thick and low Reynolds airfoil of wind turbines by mounting indented Gurney flaps was carried out. The influenced rules of the position of Gurney flaps on the aerodynamic performance of airfoil under same height of flaps were achieved, and the optimal position of Gurney flap was presented. At last, the mechanism of wind turbine performance controlled by Gurney flap was discussed. The results can provide the theoretical guidance and technical support to wind turbines control in practical engineering.

Numerical Investigation of a Cryogenic Liquid Turbine Performance and Flow Behavior

2008 ◽  
Author(s):  
Wei Zhao ◽  
Jinju Sun ◽  
Hezhao Zhu ◽  
Cheng Li ◽  
Guocheng Cai ◽  
...  
Keyword(s):  
Numerical Investigation ◽  
Large Scale ◽  
Flow Behavior ◽  
Cryogenic Liquid ◽  
Air Separation ◽  
Design Flow ◽  
Suction Surface ◽  
Navier Stokes Equation ◽  
Separation Unit ◽  
Turbine Performance

A single stage cryogenic liquid turbine is designed for a large-scale internal compression air-separation unit to replace the Joule-Thompson valve and recover energy from the liquefied air during throttling process. It includes a radial vaned nozzle, and 3-dimensional impeller. Numerical investigation using 3-D incompressible Navier-Stokes Equation together with Spalart-Allmaras turbulence model and mixing plane approach at the impeller and stator interface are carried out at design and off-design flow. At design condition, recovered shaft power has amounted to 185.87 kW, and pressure in each component decreases smoothly and reaches to the expected scale at outlet. At small flow rates, flow separation is observed near the middle section of blade suction surface, which may cause local vaporization and even cavitation. To further improve the turbine flow behavior and performance, geometry parametric study is carried out. Influence of radial gap between impeller and nozzle blade rows, and nozzle stagger angle on turbine performance are investigated and clarified. Results arising from the present study provide some guidance for cryogenic liquid turbine optimal design.

Experimental Comparison of Axial Turbine Performance Under Steady and Pulsating Flows

2014 ◽  
Vol 136 (11) ◽  
Author(s):  
A. St. George ◽  
R. Driscoll ◽  
E. Gutmark ◽  
D. Munday
Keyword(s):  
Incidence Angle ◽  
Experimental Comparison ◽  
Strong Function ◽  
Axial Turbine ◽  
Turbine Efficiency ◽  
Turbine Performance ◽  
Pulsed Detonation ◽  
Pulsed Flow ◽  
Partial Admission ◽  
Corrected Flow

The performance of an axial turbine is studied under close-coupled, out-of-phase, multiple-admission pulsed air flow to approximate turbine behavior under pulsed detonation inflow. The operating range has been mapped for four frequencies and compared using multiple averaging approaches and five formulations of efficiency. Steady performance data for full and partial admission are presented as a basis for comparison to the pulsed flow cases. While time-averaged methods are found to be unsuitable, mass-averaged, work-averaged, and integrated instantaneous methods yield physically meaningful values and comparable trends for all frequencies. Peak work-averaged efficiency for pulsed flow cases is within 5% of the peak steady, full admission values for all frequencies, in contrast to the roughly 15–20% performance deficit experienced under steady, 50% partial admission conditions. Turbine efficiency is found to be a strong function of corrected flow rate and mass-averaged rotor incidence angle, but only weakly dependent on frequency.

Experimental Comparison of Axial Turbine Performance Under Steady and Pulsating Flows

2014 ◽  
Author(s):  
A. St. George ◽  
R. Driscoll ◽  
E. Gutmark ◽  
D. Munday
Keyword(s):  
Incidence Angle ◽  
Experimental Comparison ◽  
Strong Function ◽  
Axial Turbine ◽  
Turbine Efficiency ◽  
Turbine Performance ◽  
Pulsed Detonation ◽  
Pulsed Flow ◽  
Partial Admission ◽  
Corrected Flow

The performance of an axial turbine is studied under close-coupled, out-of-phase, multiple-admission pulsed air flow to approximate turbine behavior under pulsed detonation inflow. The operating range has been mapped for four frequencies and compared using multiple averaging approaches and five formulations of efficiency. Steady performance data for full and partial admission are presented as a basis for comparison to the pulsed flow cases. While time-averaged methods are found to be unsuitable, mass-averaged, work-averaged, and integrated instantaneous methods yield physically meaningful values and comparable trends for all frequencies. Peak work-averaged efficiency for pulsed flow cases is within 5% of the peak steady, full admission values for all frequencies, in contrast to the roughly 15–20% performance deficit experienced under steady, 50% partial admission conditions. Turbine efficiency is found to be a strong function of corrected flow rate and mass-averaged rotor incidence angle, but only weakly dependent on frequency.

Numerical Investigation of Losses Due to Unsteady Effects in Axial Turbines

2003 ◽  
Author(s):  
Michael Moczala ◽  
Ernst von Lavante ◽  
Manuchehr Parvizinia
Keyword(s):  
High Pressure ◽  
Numerical Investigation ◽  
Research Work ◽  
Navier Stokes ◽  
Loss Assessment ◽  
Physical Explanation ◽  
Axial Turbine ◽  
Loss Coefficients ◽  
Axial Turbines ◽  
Unsteady Effects

Understanding of losses caused by unsteady effects is essential in efforts to improve the efficiency of modern turbomachines. In the present research work, the unsteady midspan flow in a typical high pressure axial turbine was investigated using a compressible Navier Stokes solver. The aim of this study was to take a closer look at trends in the loss behavior depending on several flow and geometry parameters as well as to give a physical explanation of these trends. Two different definitions of loss coefficients were also employed for the loss assessment and its suitability for evaluation of “unsteady losses” was discussed considering accuracy and physical aspects.

scholarly journals Axial Turbine Performance Estimation During Dynamic Operations

2020 ◽  
Author(s):  
Razvan Nicoara ◽  
Valeriu Vilag ◽  
Jeni Vilag ◽  
Zoltan Kolozvary
Keyword(s):  
Performance Estimation ◽  
Axial Turbine ◽  
Turbine Performance
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