Parametric Study and Design of Tab Shape for Improving Aerodynamic Performance of Rotor Blade

  • Jaeseong Han
  • Oh Joon Kwon
Original Paper


In the present study, the parametric study was performed to analyze the effect of the tab on the aerodynamic performance and characteristics of rotor blades. Also, the tab shape was designed to improve the aerodynamic performance of rotor blades. A computational fluid dynamics solver based on three-dimensional Reynolds averaged Navier–Stokes equation using an unstructured mesh was used for the parametric study and the tab design. For airfoils, the effect of length and angle of a tab was studied on the aerodynamic characteristics of airfoils. In addition, including those parameters, the effect of a span of a tab was studied for rotor blades in hovering flight. The results of the parametric study were analyzed in terms of change of the aerodynamic performance and characteristics to understand the effect of a tab. Considering the analysis, the design of tab shape was conducted to improve the aerodynamic performance of rotor blades. The simply attached tab to trailing edge of the rotor blades increases the thrust of the rotor blades without significant changing of aerodynamic characteristics of the rotor blades in hovering and forward flight.


Parametric study Tab Rotor blade Aerodynamic performance 

List of symbols

\(C_\mathrm{l}, C_\mathrm{d}\)

Lift and drag coefficient of an airfoil

\(C_{m, 1/4}\)

Moment coefficient of an airfoil at 1/4-chord

\(C_\mathrm{T}, C_\mathrm{P}, C_\mathrm{Q}\)

Thrust, power, and torque coefficient


Convective fluxes


Figure of merit

\(F_\mathrm{th}, F_\mathrm{tq}, F_\mathrm{D}\)

Sectional thrust, torque, and drag forces, N/m


Diffusive fluxes

l / c

Ratio of tab length to chord length


Sectional pitching moment, \(\hbox {N}\times \hbox {m}/\hbox {m}\)


Number of blades


Conservative variables


Radius of the rotor blade, m

r / R

Non-dimensional position in radial direction


Source term


Arbitrary control volume

w / R

Ratio of tab span to blade radius

\(\delta \)

Deflection angle of tab, deg

\(\lambda \)

Inflow ratio

\({\upsigma }\)


\(\phi \)

Relative inflow angle, deg

\(\partial V\)

Boundary of control volume



This work was conducted at High-Speed Compound Unmanned Rotorcraft (HCUR) research laboratory with the support of Agency for Defense Development (ADD). The authors also would like to acknowledge the support from the KEIT Research Grant of 2017 (10053157).


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Copyright information

© The Korean Society for Aeronautical & Space Sciences and Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Department of Aerospace EngineeringKorea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea

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