Controllability Analysis of Flexible Variable Sweep Control Wing

Variable Sweep Control Wing (VSCW) was introduced to generate the rolling control moment with the sweep angle differences between the left and the right wings. Influence flexible matrixes were generated to obtain the deflection of the effective angle of attack (AOA) of the flexible swept wing. Comparison between aileron control surface and VSCW shows that VSCW can get benefit from wing flexibility, which degrades the control effectiveness of the traditional aileron. The main advantage and difference from the traditional aircraft is that VSCW has higher control effectiveness and can prevent control reversal especially at high flight speed range; and at low speed, with an AOA variation device VSCW can get similar rolling control performance compared with traditional aileron control surface.

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Instantaneous Phase Detection for Performance Verification of Tuned Mass Dampers

Volume 8: Seismic Engineering ◽

10.1115/pvp2015-45978 ◽

2015 ◽

Author(s):

Ging-Long Lin ◽

Chi-Chang Lin

Keyword(s):

Power Flow ◽

Phase Detection ◽

Control Performance ◽

Tuned Mass Dampers ◽

Civil Structures ◽

Theoretical Derivation ◽

Control Effectiveness ◽

Instantaneous Phase ◽

Mass Damper ◽

The Right

Vibration control using tuned mass damper (TMD) for civil structures has been widely accepted and used in buildings and bridges. However, the TMD provides a frequency-dependent damping for the primary structure. The control effectiveness of TMD will vary with the frequency content of the excitation. A method to verify the control performance of TMD is lack in the literatures. In this study, two simple indicators were developed to judge the TMD control performance based on the theoretical derivation, which indicates the maximum power flow is occurred when the TMD stroke lags the structural displacement by ninety degree. The proposed indicators were verified by numerical simulation. The results show the proposed indicators can judge the effective of TMD correctly. In addition, the waveform of the instantaneous phase is helpful to adjust the TMD stiffness to the right value.

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Effect of Stator Design on Stator Boundary Layer Flow in a Highly Loaded Single-Stage Axial-Flow Low-Speed Compressor

Journal of Turbomachinery ◽

10.1115/1.1370168 ◽

2000 ◽

Vol 123 (3) ◽

pp. 483-489 ◽

Cited By ~ 23

Author(s):

Jens Friedrichs ◽

Sven Baumgarten ◽

Gu¨nter Kosyna ◽

Udo Stark

Keyword(s):

Axial Flow ◽

Leading Edge ◽

Single Stage ◽

Swept Wing ◽

Sweep Angle ◽

Low Speed ◽

Overall Performance ◽

Layer Flow ◽

Stator Design ◽

Highly Loaded

The paper describes an experimental investigation of the stator hub and blade flow in two different stators of a highly loaded single-stage axial-flow low-speed compressor. The first stator (A) is a conventional design with blades of rectangular planform. The second stator (K) is an unconventional, more advanced design with blades of a special planform, characterized by an aft-swept leading edge with increasing sweep angle toward hub and casing. The experimental results show that stator K exhibits a much better hub performance than stator A, finally leading to a better overall performance of stage K compared to stage A. The better hub performance of stator K is, primarily, the result of a planform effect of the newly introduced blades with an aft-swept leading edge and the aerodynamics of an aft-swept wing.

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Effect of Stator Design on Stator Boundary Layer Flow in a Highly Loaded Single-Stage Axial-Flow Low-Speed Compressor

Volume 1: Aircraft Engine; Marine; Turbomachinery; Microturbines and Small Turbomachinery ◽

10.1115/2000-gt-0616 ◽

2000 ◽

Cited By ~ 5

Author(s):

Jens Friedrichs ◽

Sven Baumgarten ◽

Günter Kosyna ◽

Udo Stark

Keyword(s):

Axial Flow ◽

Leading Edge ◽

Single Stage ◽

Swept Wing ◽

Sweep Angle ◽

Low Speed ◽

Overall Performance ◽

Layer Flow ◽

Stator Design ◽

Highly Loaded

The paper describes an experimental investigation of the stator hub and blade flow in two different stators of a highly loaded single-stage axial-flow low-speed compressor. The first stator (A) is a conventional design with blades of rectangular planform. The second stator (K) is an unconventional, more advanced design with blades of a special planform, characterized by an aft-swept leading edge with increasing sweep angle towards hub and casing. The experimental results show that stator K exhibits a much better hub performance than stator A, finally leading to a better overall performance of stage K compared to stage A. The better hub performance of stator K is, primarily, the result of a planform effect of the newly introduced blades with an aft-swept leading edge and the aerodynamics of an aft-swept wing.

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