Flow over an airfoil

AIM:- Model the flow over a NACA0017 airfoil.

1. Objective:-

To Model, the flow over a NACA0017 airfoil For the angle of attacks 0,2,4,6,8,10 and compare the lift and drag forces

2. Basic:-

2.1 Airfoil Terminologies:

Airfoil is defined as the part of the body part that is placed in the airplane to produce the most useful aerodynamic energy in an efficient way. The wing components, propeller blades, windmill blades, compressor and turbine blates on the jet engine and hydrofoils are examples of aircraft. Keywords are related to airfoil as shown below.

1. Angle of attack:

The angle of the attack is between the chord line of the airfoil and the incoming wind. A symmetrical airfoil will be able to deliver a zero lift with a zero angle of attack. But as the angle of attack increases, the air is separated at a greater angle and part of the effect of the airstream channel, leads to further elevation. At small angles, a compatible airfoil will produce a lifting force approximately equal to the angle of attack.

1. Drag Force:

`F_d=1/2⋅ρ⋅v2⋅C_d⋅A`

Where:-

Fd=Fd= Drag force;

ρ = Density of fluid;

v = speed of the object relative to the fluid;

Cd=Cd= Drag Coefficient;

A = Cross-sectional Area.

iii. Lift Force:

Lift depends on the size of the wing, being approximately proportional to the wing area. It is often convenient to quantify the lift of a given airfoil by its lift coefficient, which defines its overall lift in terms of a unit area of the wing.

`L=1/2⋅ρ⋅v2⋅C/L⋅A`

Where:-

L = Lift force;

ρ = Density of fluid;

v = speed of the object relative to the fluid;

`C_L`= Lift Coefficient`

A = Projected Area.

2.2 Other Terminologies:

1. Computational Domain and its Dimensions:
2. Computational domain and size:

Computational Dut is a simple form of visual interface that is sufficient to look at Geometry in measurement and to set boundary conditions.

This simple form should keep all the important aspects of the problem. by considering this as the nature of the system the boundary condition is given accordingly. here Cylindrical geometry. also, the size of the base provided for the computational domain is as shown below.

1. Total Analysis time(TAT):-The total analysis time defines the physical time period until which the simulation will be run from its initial instant of time.

iii. Output time steps(OTS):- Time step is used in transient solving which denotes the time interval for which the simulation will progress between each iteration/step. in our simulation the time step is 10 for each case.

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3. Procedure: -

Step 1: Import Curve data into Solidworks using the input option.

Step 2: After importing the data from the NACA0017 airfoil turn it into a sketch using the frames item.

Step 3: After closing the open end of the collar we rotated the model to a different angle (as required in different cases) with the help of rotation option. It then transfers it to the desired size as shown below.

Step 4: Utilization of the applied flow flow for analysis. After that, we set up a wizard. In the wizard, we select the external flow option and the velocity in x-direction is 600 m / s (In all cases).

Step 5: Set the mesh automatically and took the local mesh option and selected airfoil location for a better view.

Step 6: Setting the Computational domain to 2D for simulation and size. 10m in x-vertical direction, -5m in x-direction, 2.5m in y-direction, 2.5m in y-

Step-7: Inserted cut plot and goal for output result and run the calculation.

4. Simulation and Analysis:-

Simulation parameters:

Unit	: SI
Flow type	: External Flow Time-dependent
Total Analysis Time	: 5 sec
Output Time Step	: 1 sec
Working Fluid	: Air
Velocity in x-direction	: 600m/s
Velocity in Y & Z direction	: 0

4.1 Angle of attack 0 Degree:

Output:

4.2 Angle of attack 2 Degree:

Output:

4.3 Angle of attack 4 Degree:

Output:

4.4 Angle of attack 6 Degree:

Output:

4.5 Angle of attack 8 Degree:

Output:

4.6 Angle of attack 10 Degree:

Output:

5. Observation and Conclusion:-

Angle of Attack	Avg. Drag force	Avg. Lift Force
0	429.3711	-0.18515
2	416.056	925.38
4	585.54	2299.2
6	786.7	3417.819
8	1069.159	4520.935
10	1404.1957	5612

5.1 Average Drag force (Vs) Angle of attack:

X-axis: Angle of Attack

Y-axis: Average Drag force

5.2 Average Lift force (Vs) Angle of attack:

X-axis: Angle of Attack

Y-axis: Average Lift force

5.3 Comparing Drag force (Vs) Lift force:

1. During Attack zero degree We see that the airflow is evenly distributed which indicates that the same liquid flows over the airfoil. The gravitational force increases at first until it reaches a certain limit and then almost always, while the lifting force changes continuously and the Normal value is closer to Zero.
2. Here, we can see the blue circuit on the front surface of the Airfoil exposed water flow indicating that the point where the static pressure is high and the velocity is low is also known as the Stagnation point.
3. From the structure of the A average Drag Force in relation to the attack angle, we see that, as the attack angle rises the Drag Force also increases and makes a slight bend, while from the force of the Elevation Force in relation to the angle of attack, we see that, as the angle of attack rises, force raises and shows an equal relationship between them. The Lift is a component of this force in relation to the forthcoming flow and gravitational force, which is part of the force associated with the direction of flow. Lift the assembly in a vertical direction to withstand the force of gravity, but it can work in any direction along the flow path.
4. Also, as the attack angle increases, the air is distorted at a greater angle and the upper part of the airstream channel increases, leading to more altitude. At small angles, a compatible airfoil will produce a lifting force approximately equal to the angle of attack.

Reference:

https://en.wikipedia.org/wiki/Lift_(force)#:~:text=A%20fluid%20flowing%20around%20the,parallel%20to%20the%20flow%20direction.