Active Control for Wall Drag Reduction: Methods, Mechanisms and Performance

Abstract

Active reducing the skin friction drag of vehicles (such as missiles, rockets, aircraft, high-speed train, submarines, etc.) during the navigation process can improve the respond speed effectively, save the energy consumption and increase the endurance time. As lots of active drag reduction methods were proposed for different applications, a review article is urgently needed to guide researchers to choose suitable methods for their pre-research. In this review, the generation mechanisms of skin friction drag under the action of disturbing the turbulent boundary layer are discussed, and the main active drag reduction methods are summarized. According to the actuation modes, we divided the active drag reduction methods into: drag reduction based on wall motion; drag reduction based on volume force control; drag reduction based on wall deformation and drag reduction based on micro vibration generated by piezoelectric actuator. The development status, drag reduction mechanisms, typical structures and drag reduction performance of each active drag reduction method are discussed and summarized in this work, which can provide preliminary research references for those who are engaged in the research of active wall drag reduction. INDEX TERMS Drag reduction, active control methods, piezoelectric actuator, skin friction drag, turbulent boundary layer.

A review of turbulent skin-friction drag reduction by near-wall transverse forcing

“…The discussion of spanwise wall motion is brief, covering some major observations derived from DNS studies on the optimum choice of actuation parameters, and power-saving issues. More recent reviews on flow control that discuss spanwise wall oscillations are by Asidin et al [2019] and Zhang et al [2020]. In addition, a few books on turbulence and flow control contain chapters devoted to the oscillating-wall technique, e.g., Fan and Dong [2016], Soldati and Monti [2014], Tardu [2017].…”

Current state and future trends in boundary layer control on lifting surfaces

“…They considered both active (synthetic jets, dynamic pins) and passive (static pins/vortex generators) devices individually as well as a combination, thus generating a hybrid actuator that has potential to be a more efficient controller than the baseline devices for certain flow fields. In their review, Zhang et al 21 focused their attention on active wall drag reduction. They summarized previous works on actively disturbing the turbulent boundary layer in order to reduce the skin-friction drag of vehicles by one of the following: wall motion, wall deformation, wall micro oscillation, or effects of volume force.…”

Influence of Synthetic Jets on Multiscale Features in Wall-Bounded Turbulence

“…Wall turbulence drag reduction technologies have represented a dramatic topic in aerospace and other engineering applications over the past few decades as a result of the oil crisis in the early 1970s [1]. So far, various control schemes [2] have been put forward with remarkable success and are of great significance in improving the performance of vehicles and saving energy [3].…”