Three-Dimensional Separated Flow Field in the Endwall Region of an Annular Compressor Cascade in the Presence of Rotor-Stator Interaction: Part 2—Unsteady Flow and Pressure Field

1990 ◽  
Vol 112 (4) ◽  
pp. 679-688 ◽  
Author(s):  
H. D. Schulz ◽  
H. E. Gallus ◽  
B. Lakshminarayana
Keyword(s):  
Boundary Layers ◽  
Pressure Field ◽  
Pressure Fluctuations ◽  
Three Dimensional ◽  
Separated Flow ◽  
Leading Edge ◽  
Fast Response ◽  
Compressor Cascade ◽  
Rotor Stator Interaction ◽  
Detailed Interpretation

An experimental study of the unsteady three-dimensional flow and pressure field in an annular compressor cascade with an upstream rotor has been carried out at several incidences to the stator blade. The distributions of the unsteady pressures at the blade surfaces are measured using fast response Kulite sensors. The unsteady blade boundary layers and the passage flow are measured with a hot-wire sensor. A detailed interpretation of the magnitude of unsteady pressures, phase angle differences, unsteady blade boundary layers, and wake transport through the stator passage is presented and analyzed in the paper. The unsteady pressures are found to be dominant near the blade leading edge. Substantially higher pressure fluctuations occur in this region as well as on the edge of the corner flow separation region.

Three-Dimensional Separated Flow Field in the Endwall Region of an Annular Compressor Cascade in the Presence of Rotor-Stator Interaction: Part II — Unsteady Flow and Pressure Field

1989 ◽  
Author(s):  
H. D. Schulz ◽  
H. E. Gallus ◽  
B. Lakshminarayana
Keyword(s):  
Boundary Layers ◽  
Pressure Field ◽  
Pressure Fluctuations ◽  
Three Dimensional ◽  
Separated Flow ◽  
Leading Edge ◽  
Fast Response ◽  
Compressor Cascade ◽  
Rotor Stator Interaction ◽  
Detailed Interpretation

An experimental study of the unsteady three-dimensional flow and pressure field in an annular compressor cascade with an upstream rotor has been carried out at several incidences to the stator blade. The distribution of the unsteady pressures at the blade surfaces are measured using fast response Kulite sensors. The unsteady blade boundary layers and the passage flow is measured with a hot wire sensor. Detailed interpretation of the magnitude of unsteady pressures, phase angle differences, unsteady blade boundary layers, wake transport through the stator passage is presented and analyzed in the paper. The unsteady pressures are found to be dominant near the blade leading edge. Substantially higher pressure fluctuations occur in this region as well as on the edge of the corner flow separation region.

Three-Dimensional Separated Flow Field in the Endwall Region of an Annular Compressor Cascade in the Presence of Rotor-Stator Interaction: Part I — Quasi-Steady Flow Field and Comparison With Steady-State Data

1989 ◽  
Author(s):  
H. D. Schulz ◽  
H. E. Gallus ◽  
B. Lakshminarayana
Keyword(s):  
Flow Field ◽  
Separation Bubble ◽  
Three Dimensional ◽  
Separated Flow ◽  
Major Influence ◽  
Compressor Cascade ◽  
Three Dimensional Flow ◽  
Dimensional Flow ◽  
Corner Flow ◽  
Rotor Stator Interaction

An experimental study of three-dimensional flow field in an annular compressor cascade with an upstream rotor has been carried out at four different incidences to the stator blade. Blade boundary layers and the three-dimensional flow field at the exit are surveyed using a hot wire sensor and a five hole probe, respectively. The data on the blade boundary layer, passage flow and separated corner flow is presented. The upstream rotor wake has a major influence on the transition, laminar separation bubble, extent of wall/corner flow separation, aerodynamic losses, secondary flow and three-dimensional flow inside the passage. Detailed interpretation of the effects of upstream wakes on the entire passage flow is presented and compared with the data in the absence of a rotor.

Three-Dimensional Separated Flow Field in the Endwall Region of an Annular Compressor Cascade in the Presence of Rotor-Stator Interaction: Part 1—Quasi-Steady Flow Field and Comparison With Steady-State Data

1990 ◽  
Vol 112 (4) ◽  
pp. 669-678 ◽  
Author(s):  
H. D. Schulz ◽  
H. E. Gallus ◽  
B. Lakshminarayana
Keyword(s):  
Flow Field ◽  
Separation Bubble ◽  
Three Dimensional ◽  
Separated Flow ◽  
Major Influence ◽  
Compressor Cascade ◽  
Three Dimensional Flow ◽  
Dimensional Flow ◽  
Corner Flow ◽  
Rotor Stator Interaction

An experimental study of three-dimensional flow field in an annular compressor cascade with an upstream rotor has been carried out at four different incidences to the stator blade. Blade boundary layers and the three-dimensional flow field at the exit are surveyed using a hot-wire sensor and a five-hole probe, respectively. The data on the blade boundary layer, passage flow, and separated corner flow are presented. The upstream rotor wake has a major influence on the transition, laminar separation bubble, extent of wall/corner flow separation, aerodynamic losses, secondary flow, and three-dimensional flow inside the passage. A detailed interpretation of the effects of upstream wakes on the entire passage flow is presented and compared with the data in the absence of a rotor.

Effect of Clocking on the Second Stator Pressure Field of a One and a Half Stage Transonic Turbine

2004 ◽  
Author(s):  
J. Gadea ◽  
R. De´nos ◽  
G. Paniagua ◽  
N. Billiard ◽  
C. H. Sieverding
Keyword(s):  
Pressure Distribution ◽  
Static Pressure ◽  
Pressure Field ◽  
Pressure Fluctuations ◽  
Leading Edge ◽  
Fast Response ◽  
Time Resolved ◽  
Pressure Transducers ◽  
Static Pressure Distribution ◽  
Transonic Turbine

This paper focuses on the experimental investigation of the time-averaged and time-resolved pressure field of a second stator tested in a one and a half stage high-pressure transonic turbine. The effect of clocking and its influence on the aerodynamic and mechanical behaviour are investigated. The test program includes four different clocking positions, i.e. relative pitch-wise positions between the first and the second stator. Pneumatic probes located upstream and downstream of the second stator provide the time-averaged component of the pressure field. For the second stator airfoil, both time-averaged and time-resolved surface static pressure fields are measured at 15, 50 and 85% span with fast response pressure transducers. Regarding the time-averaged results, the effect of clocking is mostly observed in the leading edge region of the second stator, the largest effects being observed at 15% span. The surface static pressure distribution is changed locally, which is likely to affect the overall performance of the airfoil. The phase-locked averaging technique allows to process the time-resolved component of the data. The pressure fluctuations are attributed to the passage of pressure gradients linked to the traversing of the upstream rotor. The pattern of these fluctuations changes noticeably as a function of clocking. Finally, the time-resolved pressure distribution is integrated along the second stator surface to determine the unsteady forces applied on the vane. The magnitude of the unsteady force is very dependent on the clocking position.

Three-Dimensional and Rotational Aerodynamics on the NREL Phase VI Wind Turbine Blade

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
Alvaro Gonzalez ◽  
Xabier Munduate
Keyword(s):  
Wind Turbine ◽  
Turbine Blade ◽  
Three Dimensional ◽  
Separated Flow ◽  
Leading Edge ◽  
Wind Turbine Blade ◽  
Trailing Edge ◽  
Rotating Blade ◽  
Nrel Phase Vi ◽  
Edge Separation

This work undertakes an aerodynamic analysis over the parked and the rotating NREL Phase VI wind turbine blade. The experimental sequences from NASA Ames wind tunnel selected for this study respond to the parked blade and the rotating configuration, both for the upwind, two-bladed wind turbine operating at nonyawed conditions. The objective is to bring some light into the nature of the flow field and especially the type of stall behavior observed when 2D aerofoil steady measurements are compared to the parked blade and the latter to the rotating one. From averaged pressure coefficients together with their standard deviation values, trailing and leading edge separated flow regions have been found, with the limitations of the repeatability of the flow encountered on the blade. Results for the parked blade show the progressive delay from tip to root of the trailing edge separation process, with respect to the 2D profile, and also reveal a local region of leading edge separated flow or bubble at the inner, 30% and 47% of the blade. For the rotating blade, results at inboard 30% and 47% stations show a dramatic suppression of the trailing edge separation, and the development of a leading edge separation structure connected with the extra lift.

The Effect of Aspect Ratio on Wall Pressure Fluctuations at a Wing-Plate Junction

2020 ◽  
Vol 142 (7) ◽  
Author(s):  
M. Awasthi ◽  
J. Rowlands ◽  
D. J. Moreau ◽  
C. J. Doolan
Keyword(s):  
Pressure Fluctuations ◽  
Three Dimensional ◽  
Leading Edge ◽  
Suction Side ◽  
Wide Frequency Range ◽  
Wall Pressure ◽  
Frequency Range ◽  
Three Dimensional Flow ◽  
Wall Pressure Fluctuations ◽  
Aspect Ratios

Abstract Measurements of the wall pressure fluctuations near a wing-plate junction were made for wings with three different aspect ratios (AR) of 0.2, 0.5, and 1.0 at several angles of attack. The chord-based Reynolds number for each wing was 274,000. The results show that the wall pressure fluctuations are a function of wing AR for cases where AR≤ 1.0. For each wing, the pressure fluctuations are highest upstream of the wing leading-edge due to three-dimensional flow separation; wings with AR = 1.0 and 0.5 show comparable levels, while those with AR = 0.2 show lower fluctuation levels over a wide frequency range. Downstream of the leading-edge, the pressure fluctuations decay rapidly on both sides of the wing until the maximum thickness location after which little variation is observed. The pressure fluctuations downstream of the leading-edge on the suction-side were observed to be comparable for AR = 0.2 and 0.5, while those for AR = 1.0 were higher in magnitude. On the pressure-side, the pressure fluctuations near the leading-edge are a weak function of AR; however, those further downstream remain independent of AR. The pressure fluctuations aft of the wing on the suction-side are more coherent for lower ARs and show higher convection velocity, possibly due to an interaction between the tip and the junction flows for lower ARs.

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