Flow Control Techniques: Investigating Methods to Manipulate Airflow Around Aircraft Surfaces for Improved Performance

The methods of flow control are crucial in the improvement of aircraft performance through the control of airflow on surfaces of aircraft thus leading to an increase in efficient use of air, decrease of drag and increase in lift. The present research focuses on several interventions in airflow control and classifies them into passive control, aggressive control, and combined control systems. Operations like the employment of vortex generators, boundary layer fences, and riblets are passive since they do not require energy input. These methods involve installing fixed devices to change the flow characteristics, defer the formation of flow separating, and minimize the drag, thus ideal for a particular flight condition, high lift. Real-time control methods such as synthetic jets and plasma actuators need energy supplied from external sources to control flow. Synthetic jets can produce repeated puffs of air to alter the boundary layer to avoid flow separation and minimize the drag. Plasma actuators, which ionize air, or create plasma, electrically, work faster and enable the control of flow separation and drag without mechanical parts. These active techniques give more certain and flexible control over the flight activity but they are complex and consume more power as compared to other techniques in response to changes in flights. It is worth noting that the hybrid flow control strategies use both passive and active flows to take the benefits of the two. For instance, using 'vortex generators' combined with 'synthetic jets may enhance the boundary layer and offer maximum performance at various flight conditions (Li et al., 2022). This working synergy can be considered as the improvement of the aerodynamic performance thanks to the adaptability and efficiency improvement. The paper also describes the theoretical background, application, and performance assessment of the above-mentioned flow control methods. Thus, by comparing and analyzing the existing techniques the given paper will describe the state of Flow Control Technologies and state what further directions are possible to identify in the development of advanced technologies and their influence on the development and modification of Aerospace Engineering and Aircraft Designs.