A study of turbine performance increases through airfoil clocking

Dorney, Daniel J.; Sharma, Om P.

doi:10.2514/6.1996-2816

Cited by 38 publications

(18 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the references [7][8][9][10][11][12][13], which are devoted to experimental investigations of the stators' clocking effects, it is shown that the parameter ν affects the total pressure losses in a stage of a turbomachine. Measurements were carried out, both by a rake probe of total pressure and by probes equipped with high-frequency transducers, which were shifted over the radius and measured the instantaneous values of the stagnation pressure.…”

Section: Total Pressure Losses and Vortical Wakes Of Rotormentioning

confidence: 99%

“…A direct experimental test of the clocking effect was executed for the first time during the transonic and subsonic stages of an axial compressor [5,6]. Similar experiments and a numerical analysis have been executed for turbine stages in [7][8][9]. Further experimental and numerical studies were performed for a subsonic model stage of the axial compressor 1 [10][11][12][13].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Hydrodynamic interaction of axial turbomachine cascades

et al. 2006

View full text Add to dashboard Cite

Hydrodynamic interaction of mutually moving airfoil cascades is investigated. It is shown that the semiempirical theory of potential-vortical interaction of two mutually moving cascades in incompressible flow allows one to describe correctly the features of their mutual effect for various gaps between cascades and relations of their pitches. Application of the above theory to a flow around three cascades of the stator-rotor-stator type allows to determine the basic mechanism of the stators' mutual shift effects (clocking effects). To close the theory regarding the vortical interaction of cascades, a semi-empirical model of turbulent diffusion in a non-uniform flow of the periodic vortices descending from airfoils is proposed. Theoretical results are compared with data from numerical and physical experiments. Comparison with results of numerical modeling is based on the solution of the Reynolds equations for a viscous gas closed by the (q-ω) model of turbulence. Results published here and elsewhere are used for comparison with measurement data.

show abstract

Section: Total Pressure Losses and Vortical Wakes Of Rotormentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Hydrodynamic interaction of axial turbomachine cascades

et al. 2006

View full text Add to dashboard Cite

show abstract

“…Huber [4'5], Saren [6], Gundy-Burlet I1], Dorney [3,8,91, Citzmas [2], Sharma t3j, Barankiewicz tT] et al did a lot of fruitful researches by means of experimental, analytical and numerical technique. The results show that the airfoils clocking may have significant effect on the operation performance of the turbomachines.…”

Section: Received 2003mentioning

confidence: 99%

“…Wake interaction is the main contribution of the unsteady vortical effect during the airfoil interaction. The vortical and entropic wakes shed by one or more upstream rows interact with the downstream airfoils and other wakes [1][2][3].…”

Section: Introductionmentioning

confidence: 99%

Clocking effect in a two-stage compressor with different inter-blade-row gaps

et al. 2004

View full text Add to dashboard Cite

A multi-stage axial compressor has inherently unsteady flow fields because of the following main reasons: (1) relative positions between rotor and stator airfoil; (2) the buildup of converted wakes lead to complex wake/wake and wake/airfoil interactions. The distributions of the potential flows and wakes in the flow passage are depended on the relative positions of blade rows in axial and circumference direction, so variations in the relative axial positions (axial gap) and circumferential positions (clocking effect) of stators or rotors can change these distributions, leading to different compressor efficiency. The current study presents the experimental/numerical result of a low-speed axial compressor, considering the combined effects of stator clocking and variation of axial gaps. Testing was conducted in Two-Stage Axial Compressor Facility in Harbin Institute of Technology. In the test, time averaged data were collected. The results of experimental and time accurate flow calculation for 2 axial gaps, 8 clocking positions for each gap axe compared. It is shown that clocking determines the degree of interaction of a stator with the wake of another upstream stator for different gaps between the blade rows.

show abstract

“…However, the predicted efficiency variation was only 0.5%. Clocking effects in a l(1/2)-stage turbine have also been numerically simulated by Eulitz et al (Eulitz, Engel and Gebbing, 1996) and Dorney and Sharma (Dorney and Sharma, 1996). The effects of airfoil clocking on a six-row turbine have been also investigated (Cizmas and Dorney, 1999b).…”

Section: Introductionmentioning

confidence: 99%

Influence of Inter‐row Gap Value on Turbine Losses

Cizmas

Hoenninger

Chen

et al. 2000

International Journal of Rotating Machinery

View full text Add to dashboard Cite

This paper presents the results of a numerical investigation of the gap influence on the turbine efficiency. The rotor-stator interaction in a (1/2)-stage turbine is simulated by solving the quasi-three-dimensional unsteady Euler/Navier-Stokes equations using a parallelized numerical algorithm. The reduced turnaround time and cost/MFLOP of the parallel code was crucial to complete the numerous run cases presented in this paper. The inter-row gap effect is evaluated for 4 gaps, 3 radial positions and 3 angular velocities. As expected, the results presented in this paper show that the efficiency increases and losses decrease while the gap size increases. The maximum efficiency location, however, corresponds to values of the gap size which may be too large for practical use (approximately inch). Fortunately, a local maximum efficiency and minimum losses location has been found at approximately 0.5 inches gap size. The efficiency variation near the local optimum is large, in some configurations being as high as 1.4 points for a gap size variation of only 0.076 inches. Data produced by the numerical simulations can be used to develop a design rule based on the inter-row gap size.

show abstract

A study of turbine performance increases through airfoil clocking

Cited by 38 publications

References 15 publications

Hydrodynamic interaction of axial turbomachine cascades

Hydrodynamic interaction of axial turbomachine cascades

Clocking effect in a two-stage compressor with different inter-blade-row gaps

Influence of Inter‐row Gap Value on Turbine Losses

Contact Info

Product

Resources

About