Learning Forum

[watchdog23]

Hey, I'm in my final year of my B.E. and i want some help regarding our project in ANSYS. We've modeled a pelton bucket, not the whole turbine, but only a section of it and are planning to use the symmetry function for the whole analysis.

Static analysis of the bucket is one of the part of analysis, and we are stuck on how we should proceed about it, as ANSYS is not our strong forte. We all know the basic functions, and since the time is limited, if someone who has done his/her projects in the same field or has knowledge on how to proceed on about it, it'd be a great help to us!

 

 Here's an image of our 3D model.

 

 

[peteroznewman]

Hey, I'm willing to help. I even looked up what a Pelton bucket was.

The steps to perform a Static Structural model include:

Defining how the model is supported. It looks like you cut a slice of the support wheel out with that tapered section. You say you will use symmetry which means you will just have 1 cup and 1/2 the water. You can use symmetry conditions on the two tapered faces and those three will hold the part fixed.

Defining how the forces are applied. A Pelton bucket is moving away from the water jet that is impinging. The water jet starts at one angle of attack at the tip of the bucket when it first touches the jet, then is normal to the jet, which is impinging closer to the axis, then the bucket leaves the jet at the opposite angle of attack. Do you know how much force and in which direction the forces are on the face?  You could run a CFD model to calculate that and transfer those loads to the structure. I did this recently to calculate the wind pressure on a concrete dome.  A somewhat relevant example is this air turbine tutorial that Raef provided.

[watchdog23]

Hey! Sorry for replying so late. This final year thing has got us very busy.
We also did the exact thing as you mentioned above, and after a lot of binge watching youtube videos and reading stuffs, we finally got the value of stress within 1% error.
While CFD is very intriguing, but the dynamic analysis using CFD is somewhat out of our scope, I have read some Master thesis on the said topic and will be very time consuming.
So, we made the decision of sticking to the static analysis and proceed with the observed results.
Nevertheless, thank you for your suggestions, means a lot.

P.S. I'd like to ask you something, how do we get so good in ANSYS? Are there any materials like books or anything that will help us learn ANSYS in a more understanding and efficient way.
And also, if anything comes along the way, hope you wind mind a help post from me again!

Lastly, Thank you for your help and also for the videos. And also for the suggestion!

 

[peteroznewman]

Hey! You're welcome. The way I'm trying to get good in ANSYS is by answering questions on this site. I recommend you take the free course on edX.org, "A Hands-on Introduction to Engineering Simulations" developed by Cornell University. It takes you through four modules that lay a foundation of understanding and covers thermal models, structural models and a couple of CFD models. I took this course in 2017, and that was my first exposure to CFD, now I am helping others with the simplest models. BTW, I think a jet of water into the bucket would be a very challenging model for me too!  

Good luck in your final year. I look forward to any more posts you care to send along.

Regards.