عنوان مقاله [English]
Active control of airflow by using Dielectric-Barrier-Discharge (DBD) is a recent development in flow control theory. Low-weight, low power consumption, no moving parts and flexibility of use are some of its advantages over passive control methods.
In this paper, a User Defined Function (UDF) code was hooked into the main flow solver code to model the momentum injected to the flow by DBD actuator. Among different methods that were proposed, Shyy numerical method is selected. The selection process is based on pros and cons of different first principle and phenomenological methods which were published in recent years.
In order to validate the results of the air flow in the presence of DBD actuator two test cases are selected, the flow around the Flat Plate and NACA 0015 airfoil. Different flow variables including the velocity profile and pressure distributions are obtained and compared to the reference data. 3D effects of DBD actuators are also investigated by using a NACA 0015 wing model. Two tests are carried out. First, the effect of doubling the DBD field is studied. After doubling the strength of DBD field, the control power of actuator enhanced. Pressure distribution in the midpoint of wing clarifies this fact. Second, the effect of span-wise DBD actuators is investigated. In three locations DBD roll installed on the wing platform and its effect on the flow variables carried out. This experiment clarified that the best location to use DBD plasma actuators would be the onset of flow separation. In this location, the lift to drag ratio of the wing is maximum.
Also we studied the DBD parameters which affect the Ionic wind strength, Frequency and Voltage of the power supply. Increasing voltage and frequency would make plasma more effective (this is also concluded from lift to drag ratio) but the trend is not linear for voltage.