Hung Truong, Abderahmane Marouf, Alain Gehri, Jan Vos, Marianna Braza and Yannick Hoarau
This study aims to investigate the physical mechanisms of the use of active flow control (AFC) for a high-lift wing-flap configuration.
Abstract
Purpose
This study aims to investigate the physical mechanisms of the use of active flow control (AFC) for a high-lift wing-flap configuration.
Design/methodology/approach
By means of high-fidelity numerical simulations, the flow dynamics around a high-lift wing-flap system at high Reynolds number (Re/c = 4.6 million) is studied. Adapted turbulence models based on the URANS approach are used to capture the flow separation and the subsequent development of coherent structures. The present study focuses on the use of AFC using a synthetic jet known as zero-net-mass-flux (ZNMF) using the blowing–suction approach. Different parameters (geometry, frequency and velocity) of a ZNMF placed at the cambered flap’s chord are optimized to obtain the most efficient parameter settings to suppress the flow separation.
Findings
A synthetic jet with the optimal shape and orientation enforces the flow reattachment on the wing-flap surface. This leads to an improvement of the aerodynamic performance of the system. The wake thickness was reduced by 30%, and an increase of 17.6% in lift-to-drag ratio was obtained. Concerning the ZNMF location, they should be installed upstream of the separation point to achieve the best performance.
Originality/value
The effectiveness of ZNMF devices integrated on a high-lift wing-flap configuration was studied in real flight conditions at high Reynolds number. A detailed analysis of the wake dynamics explains how AFC forces the reattachment of the boundary layer and attenuates the predominant wake instabilities up to −20 dB.
Details
Keywords
This chapter treats the luxury hotel concept and practice and its recent trends in the tourism industry. This niche market is expanding rapidly with changing global income…
Abstract
This chapter treats the luxury hotel concept and practice and its recent trends in the tourism industry. This niche market is expanding rapidly with changing global income structures and increasing complexity of the hospitality sector. Its clientele comprises quality-seeking, prestige-striving, and high-spending customers. The chapter first explores the concept of luxury in relation to hotels. It further groups various associated assets into tangibles and intangibles to discuss their recent trends across the world. It is suggested that companies and destinations active in the luxury hotel market or contemplating entry take these trends into account to gain and/or maintain competitiveness.