Aerodynamic Design of High End Wall Angle Turbine Stages—Part II: Experimental Verification

2013 ◽  
Vol 136 (2) ◽  
Author(s):  
A. W. Cranstone ◽  
G. Pullan ◽  
E. M. Curtis ◽  
S. Bather
Keyword(s):  
Turbulence Modeling ◽  
Test Results ◽  
Suction Surface ◽  
Wall Angle ◽  
Computational Fluid Dynamics Cfd ◽  
The Difference ◽  
And Performance ◽  
Turbine Design ◽  
End Wall ◽  
Very High

An experimental investigation of a turbine stage featuring very high end wall angles is presented. The initial turbine design did not achieve a satisfactory performance and the difference between the design predictions and the test results was traced to a large separated region on the rear suction-surface. To improve the agreement between computational fluid dynamics (CFD) and experiment, it was found necessary to modify the turbulence modeling employed. The modified CFD code was then used to redesign the vane, and the changes made are described. When tested, the performance of the redesigned vane was found to have much closer agreement with the predictions than the initial vane. Finally, the flowfield and performance of the redesigned stage are compared to a similar turbine, designed to perform the same duty, which lies in an annulus of moderate end wall angles. A reduction in stage efficiency of at least 2.4% was estimated for the very high end wall angle design.

Aerodynamic Design of High Endwall Angle Turbine Stages: Part 2—Experimental Verification

2012 ◽  
Author(s):  
A. W. Cranstone ◽  
G. Pullan ◽  
E. M. Curtis ◽  
S. Bather
Keyword(s):  
Test Results ◽  
Aerodynamic Design ◽  
Turbine Stage ◽  
Suction Surface ◽  
Satisfactory Performance ◽  
The Difference ◽  
And Performance ◽  
Turbine Design ◽  
Stage Efficiency ◽  
Very High

An experimental investigation of a turbine stage featuring very high endwall angles is presented. The initial turbine design did not achieve a satisfactory performance and the difference between the design predictions and the test results was traced to a large separated region on the rear suction-surface. To improve the agreement between CFD and experiment, it was found necessary to modify the turbulence modelling employed. The modified CFD code was then used to redesign the vane, and the changes made are described. When tested, the performance of the redesigned vane was found to have much closer agreement with the predictions than the initial vane. Finally, the flowfield and performance of the redesigned stage are compared to a similar turbine, designed to perform the same duty, which lies in an annulus of moderate endwall angles. A reduction in stage efficiency of at least 2.4% was estimated for the very high endwall angle design.

Gas Liquid Vane Separators in High Pressure Applications

2010 ◽  
Author(s):  
Dani Fadda ◽  
David Barker
Keyword(s):  
Separation Efficiency ◽  
Pressure Vessels ◽  
Cfd Modeling ◽  
Test Results ◽  
Capacity Curves ◽  
Liquid Handling ◽  
Wide Range ◽  
Computational Fluid Dynamics Cfd ◽  
Very High ◽  
High Separation

Vane separators are inertial devices used to remove entrained liquids from gas. They are utilized in pressure vessels operating at a wide range of temperatures and pressures. Computational Fluid Dynamics (CFD) modeling and sizing calculations are used to evaluate the loading to a vane separator and determine the maximum overall gas and liquid handling capacity of the pressure vessel. Test results, performed at operating pressures up to 133 bar (1931 psia) using live natural gas illustrate that, when sized correctly based on the vane’s capacity curves and CFD modeling, vane separators continue to have high separation efficiency at very high operating pressures.

Effect of Inflow Conditions on Wind Turbine Blade Performance

2013 ◽  
Author(s):  
Kiran Kumar ◽  
Sudhakar Piragalathalwar ◽  
Jitendra Bijlani ◽  
Jesper Madsen
Keyword(s):  
Wind Turbine ◽  
Flow Characteristics ◽  
Design Basis ◽  
Turbulent Inflow ◽  
Engineering Models ◽  
Wind Tunnel Data ◽  
Computational Fluid Dynamics Cfd ◽  
And Performance ◽  
Turbine Design ◽  
Inflow Conditions

One important uncertainty still associated with the design and operation of wind turbines is the response and performance characteristics for the atmospheric inflow conditions. A very important issue in wind turbine design is the validity of the models that are used in the design process, the models used in Computational Fluid Dynamics (CFD) or the aerodynamic simulations. The aerodynamic part of the design basis has been restricted to non-shear turbulent inflow conditions. Therefore, measured detailed flow characteristics on a rotor in natural, turbulent flow environment are needed to be compared with 2D/3D CFD, wind tunnel data and other aerodynamic models. This will improve the prediction of the wind turbine response, but also represent a unique validation basis for 3D CFD computations and aerodynamic engineering models. The overall objective is to validate the CFD prediction with the field measurement.

Aerodynamic Performance Prediction of a Profile in Ground Effect With and Without a Gurney Flap

2017 ◽  
Vol 139 (3) ◽  
Author(s):  
Carlo Cravero
Keyword(s):  
Experimental Data ◽  
Flow Distribution ◽  
Ground Effect ◽  
Numerical Approach ◽  
Aerodynamic Performance ◽  
Suction Surface ◽  
Gurney Flap ◽  
Computational Fluid Dynamics Cfd ◽  
And Performance ◽  
Race Cars

A very detailed experimental case of a reversed profile in ground effect has been selected in the open literature where available experimental data have been used as reference data for the computational fluid dynamics (CFD) analysis. The CFD approach has been used to predict aerodynamic performance of the profile at different distances with respect to the ground: in the freestream case, there is no ground effect whereas in the low height the profile operation is limited by the stall on the suction surface. Moreover, the effect of a Gurney flap addition on flow distribution and performance has been numerically investigated. The experimental data have been used to setup and test the capabilities of the computational approach. With the addition of a Gurney flap, a significant flow unsteadiness is introduced that needs to be considered in the numerical approach. In this case, the configurations investigated are used to highlight the capabilities of CFD using Reynolds-averaged Naiver–Stokes (RANS) approach for its effective application as a tool for the detailed design of aerodynamic components to generate downforce for race cars.

scholarly journals Methods of enlarging material to the concentration table

2019 ◽  
Vol 2 (1) ◽  
pp. 59-68
Author(s):  
Jacek Feliks ◽  
Magdalena Krawczyk
Keyword(s):  
Air Pollution ◽  
Theoretical Analysis ◽  
Perforated Plate ◽  
High Water ◽  
Test Results ◽  
Air Concentration ◽  
Enrichment Method ◽  
The Difference ◽  
Concentration Table ◽  
Very High

Abstract Concentration tables are one of the oldest oscillatory enrichments with over 100 years of tradition. On this type of distribution tables are made according to material mass in many recurring cycles induced by appropriate drives. So-called wet tables are the devices most often used for coal enrichment in Polish mines because this process generates very high costs, high water consumption and pollution of the environment, as well as the need for, among others, water and mud management is increasingly being replaced mainly in areas poor in water by the modern model of the air concentration table – FGX produced in China. The process of enrichment on this type of table itself runs in a manner comparable to the method of wet enrichment with the difference that the FGX is distributed on a perforated plate, in this case we deal with air pollution. Department of Machinery Engineering and Transport's attempts to use the differences in coefficients of friction in over-resonance screens have shown that it is possible effective separation of grains with different coefficients of friction. The article presents a theoretical analysis and presents the results of performed dry enrichment trials using different coefficients of friction. The summary presents the advantages of using the enrichment method using the differences in friction coefficients and test results.

A Modification of the Payne-Jones Method of Identifying Abnormal Differences in WISC-R Performance and Verbal IQ's

1996 ◽  
Vol 12 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Louis M. Hsu
Keyword(s):  
Full Scale ◽  
True Score ◽  
Verbal Iq ◽  
Score Difference ◽  
The Difference ◽  
And Performance

The difference (D) between a person's Verbal IQ (VIQ) and Performance IQ (PIQ) has for some time been considered clinically meaningful ( Kaufman, 1976 , 1979 ; Matarazzo, 1990 , 1991 ; Matarazzo & Herman, 1985 ; Sattler, 1982 ; Wechsler, 1984 ). Particularly useful is information about the degree to which a difference (D) between scores is “abnormal” (i.e., deviant in a standardization group) as opposed to simply “reliable” (i.e., indicative of a true score difference) ( Mittenberg, Thompson, & Schwartz, 1991 ; Silverstein, 1981 ; Payne & Jones, 1957 ). Payne and Jones (1957) proposed a formula to identify “abnormal” differences, which has been used extensively in the literature, and which has generally yielded good approximations to empirically determined “abnormal” differences ( Silverstein, 1985 ; Matarazzo & Herman, 1985 ). However applications of this formula have not taken into account the dependence (demonstrated by Kaufman, 1976 , 1979 , and Matarazzo & Herman, 1985 ) of Ds on Full Scale IQs (FSIQs). This has led to overestimation of “abnormality” of Ds of high FSIQ children, and underestimation of “abnormality” of Ds of low FSIQ children. This article presents a formula for identification of abnormal WISC-R Ds, which overcomes these problems, by explicitly taking into account the dependence of Ds on FSIQs.

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