Abstract It is known that plunging airfoil can produce both lift and thrust with certain combination of plunging amplitude and frequency. Motivated by our interest in micro air vehicles (MAVs), we utilize a NavierStokes equation solver to investigate the aerodynamics of a flapping airfoil. The roles of the plunging and pitching amplitude and frequency, and Strouhal number are studied. For a sym...

Anumerical study was conducted to investigate the effects of airfoil thickness on the thrust generation of plunging airfoils and to assess the contributions of pressure and viscous forces in flapping propulsion. A series of NACA symmetric airfoils with thickness ratio ranging from 4.0% to 20.0% of the airfoil chord length were used in the present study to undertake a same sinusoid plunging moti...

EI ρA Wn(x) eigenfunction corresponding to the n th eigenvalue Tn(t) generalized function corresponding to the n th eigenvalue Fn(t) forcing function in terms of the n th eigenmode z the deflection of the beam in the complex plane x nondimensional length scale by chord length of the NACA0012 airfoil κ Reduced plunging frequency, ωc U∞ h non-dimensional amplitude,y/c ha maximum nondimensional am...

In this paper we carry out computational studies of three-dimensional flow over flapping wings. The problems we have investigated include, firstly, three-dimensonal simulation of flow over an extruded SD7003 airfoil in plunging motion at transitional Reynolds number and, secondly, flow over a pair of flapping rectangle wings with constant NACA0012 cross-sectional airfoil profile at low Reynolds...

The fluid-structure coupling process of a plunging rigid airfoil with a thin elastic plate attached at the trailing-edge is simulated numerically by using unsteady potential flow source/vortex panel method and the Euler-Bernoulli beam vibration differential equation. The flow characteristics, the unsteady aerodynamic loads, especially the thrust effects of the plunging motion are computed. The ...

Direct numerical simulations were performed to study the effect of an elastically mounted trailing edge actuator on the unsteady flow over a plunging, thin airfoil at Reynolds number of 14700 based on the chord length. The goal is to investigate potential benefits of flow-induced passive actuation of the trailing edge to the lift and drag characteristics of flapping MAV wings. The trailing edge...

Force and supporting particle image velocimetry measurements were performed on a plunging NACA 0012 airfoil at a Reynolds number of 10,000, at pre-stall, stall, and post-stall angles of attack. The lift coefficient for pre-stall and stall angles of attack at larger amplitudes showed abrupt bifurcations with the branch determined by initial conditions. With the frequency gradually increasing, ve...

This paper presents investigation effects of a sharp edged gust on aeroelastic behavior and time-domain response of a typical section model using Jones approximate aerodynamics for pure plunging motion. Flutter analysis has been done by using p and p-k methods developed for presented finite-state aerodynamic model for a typical section model (airfoil). Introduction of gust analysis as a linear ...

This paper presents simulations of unsteady flow past a plunging airfoil using the highorder spectral difference (SD) method. Both third-order and fourth-order SD methods are used on unstructured quadrilateral grids. The vortex shedding pattern of an airfoil in an oscillating plunge motion becomes asymmetric at a sufficiently high frequency. The SD method is able to capture this effect and reve...