This paper provides an up-to-date survey of the use of zonal detached eddy simulations (ZDES) for unsteady civil aircraft applications as a reflection on the stakes and perspectives of the use of hybrid methods in the framework of industrial aerodynamics. The issue of zonal or non-zonal treatment of turbulent flows for engineering applications is discussed. The ZDES method used in this article ...

The complex and unsteady aerodynamics of vertical axis wind turbines (VAWTs) pose significant challenges for simulation tools. Recently, significant research efforts have focused on the development of new methods for analysing and optimising the aerodynamic performance of VAWTs. This paper presents an electric circuit model for Darrieus-type vertical axis wind turbine (DT-VAWT) rotors. The nove...

Abstract This paper demonstrates the importance of assessing whirl flutter stability propeller configurations with a detailed aeroelastic model instead local pylon models. Especially growing use electric motors for propulsion in air taxis and commuter aircraft becomes an important mode instability. These often include which are powered by lightweight located at remote locations, e.g. wing tip. ...

In this paper we present a model for oscillating foil propulsion in which springs are used to transmit forces from the actuators to the foil. The expressions for hydrodynamic force and moment on the foil come from classical, linear, unsteady aerodynamics, and these are coupled to linearized rigid-body mechanics to obtain the complete model for swimming. The model is presented as a low-order set...

It is not easy for the system identification-based reduced-order model ROM and even eigenmode based reduced-order model to predict the limit cycle oscillation generated by the nonlinear unsteady aerodynamics. Most of these traditional ROMs are sensitive to the flow parameter variation. In order to deal with this problem, a support vector machineSVMbased ROM was investigated and the general cons...

We present a nonlinear formulation in modal coordinates of the equations of motion of a flexible aircraft. It relies on the projection of the intrinsic equations of geometrically-nonlinear composite beams on the linear normal modes at a reference condition, which are coupled with 2D unsteady aerodynamics. The resulting description is suitable for nonlinear dynamic analysis and control design, w...

This experimental study, focusing on the effects of turbulence on long-span bridge aerodynamics, examined the anatomy of turbulence effects on the self-excited forces responsible for flutter and the spanwise correlation of the overall aerodynamic lift and moment. This examination was conducted by measuring pressure distributions around an oscillating prism. A forcedvibration system was used wit...

A summary of the propulsion system modeling under NASA’s High Speed Project (HSP) AeroPropulsoServoElasticity (APSE) task is provided with a focus on the propulsion system for the lowboom supersonic configuration developed by Lockheed Martin and referred to as the N+2 configuration. This summary includes details on the effort to date to develop computational models for the various propulsion sy...

A lightweight flapping-wing micro air vehicle (MAV) was designed and built and successfully filed in the sky. The unsteady aerodynamics associated with this MAV was detailedly studied by using the method of computational fluid dynamics (CFD).The variations of different parameters of the flapping MAV, such as flapping amplitude, pitch amplitude and flapping frequency, were investigated with nume...

Table 1: Parameters of PIV Circuit Particle image velocimetry (PIV) is used in experimental fluid dynamics to obtain a detailed localized view of velocity vectors in an unsteady fluid flow. In a nutshell, the estimated velocity field is computed from local correlations of snapshot-pairs of the particle-seeded flow, obtained by high-speed cameras [1-2]. PIV is used in a wide range of fields incl...