Introduction: Make a Simple Wells Turbine
Wells turbine is a well known turbomachinery technology which is widely used for energy(electricity) production using oscillating water column(OWC). The speciality about these types of turbine is that they rotate in only one direction irrespective of the direction of airflow. The blade profile used for this demonstration is NACA 0021 Symmetry profile (From reference people have used NACA 0021).
Making a Wells turbine is much more easier than any other turbos. For this demo I have created the above specified blade profile using cardboard. First i traced the profile image in AutoCAD using spline and scaled it to required size finally printed it in a paper. Using this as reference I modeled in cardboard. There are two tests performed in this demo. One air and the other in a bucket of water. I will explain the project in this demo.
Here is the video of the final result that you would gain from this demo.
Step 1: Making the Turbine
I have attached the dimensions which I used to make the Wells turbine (The Number are not calculated they are just guessed (If you are trying to make a Wells turbine for a real power generation then please consider the flow rate, diameter, Solidity, C/L ratio and other necessary things)
In the second image there are two holes in the bucket in which the big hole is to concentrate the air flow on to the blades and other one is to hold the turbine section.
The technique that i have used to make the airfoil is by placing the printed airfoil at three places(0-50-100) over the full span. This is clearly shown in the last picture. The advantage of this way is that we may get the same geometry over the full span.
Step 2: Assembly
Now using a sellotape paste all the blades over the disk and drill a hole at the center. Place the turbine over the bucket as shown in the pic.
Next step is to test our turbine. Before going for water test. First check whether your turbine is spinning in the same direction irrespective of the direction of air flow.