On simulating transient airflow over the airfoil in CONVERGE, the results appeared to converge at 2 seconds. Plotting Angles of Attack Vs Lift Coefficient (Steady State): Plotting Angles of Attack Vs Drag Coefficient (Steady State): At the ninth second, you will see that the flow turned spontaneous and irregular: You can watch the results in the video here. When we post-process the data into ParaView to visualize the scenario. This scenario is impracticable in real life. The result obtained is as follows:Īs you can see in the result above, the solution converged for the first 15000 cycles and then blew up due to excessive errors. However, we still simulate steady flow since we always take an industrial approach to any problem. In practical situations, a steady-state does not occur as there is always turbulence present. Result Discussion: Steady-State Simulation results: The case is then set up for steady-state and transient simulation.
It is then diagnosed for errors like intersection errors or open edges or non-manifold edges. Then, the geometry must be imported into CONVERGE STUDIO as a. the bounding box is used to determine the dimensions of any geometry. The dimensions of the airfoil by enabling the bounding box in CONVERGE STUDIO, like shown in the below image. We can now create the geometry for the airfoil.
Simulating the Airfoil Software used: CONVERGE CFD Since we are calculating the lift force for only a unit length, Since Converge always calculates force per unit length (for 2D case), the formula can be re-written as: To calculate the Lift Coefficient, we use the formula mentioned above: Since we are calculating the drag force for only a unit length, With reference to Figure 1, we can substitute the area as the multiplication of length and height of the rectangular structure: Since CONVERGE always calculates force per unit length (for 2D case), the formula can be re-written as: To calculate the Drag Coefficient, we use the formula mentioned above: When you observe the front view and the bottom view, you will see a rectangular structure like this: While calculating Lift Coefficient, we should take an area as observed from Bottom View since lift force acts in that direction.While calculating Drag Coefficient, we should take an area as observed from Front View since drag force affects this section the most.
When an airfoil is subjected to airflow, the front section and the bottom section of the airfoil encounters most of the flow.
Simultaneously, the flow of air over the body also generates a resistance called drag. when an airfoil travels through air, lift is produced. This has led to a whole new branch in the field of mechanical engineering and has allowed us to explore the atmosphere and space. Airfoil Simulation – Plotting Lift and Drag CoefficientsĪirfoils are specifically designed structures that generate lift force when air flows over it.