User Defined Functions (UDFs) are amazing when it comes to defining motion to a boundary or setting complex boundary conditions or material properties. 💡 Coded in C language, UDFs give engineers the flexibility to add more complexity to the problems they are solving. 🔧 I wrote a UDF for a simple case of 2D airfoil simulation to get my hands dirty in the UDF domain of ANSYS Fluent. The UDF rotates the airfoil periodically by +/- 20 degrees, thus periodically varying its angle of attack. ✈️ Watch how the lift and drag forces vary with the motion of the airfoil in the video below. 📽️ https://youtu.be/duv2y70omEk