CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   Main CFD Forum (https://www.cfd-online.com/Forums/main/)
-   -   Selection of Design Parameters (https://www.cfd-online.com/Forums/main/159641-selection-design-parameters.html)

Mehar September 19, 2015 13:09

Selection of Design Parameters
 
Dear All,

I have to perform design studies for developing a flow around a structure using a number of blowing towers positioned around that structure. But, I am confused about what parameters (like lift, drag, Cp, swirl ratio, vorticity, angular velocity etc), I need to take for comparison and as well as design objective for deciding which configuration of blowing towers is optimum.
The purpose of this study is to isolate that structure from surrounding environment using optimized configuration of blowing towers and blowing speed.
A simplified geometry is attached!
Any help is highly appreciated!
Thanks in Advance!

Mehar!
https://www.dropbox.com/sc/giv3u0rsv...x8A5duPwjBeRRa

Mehar September 21, 2015 07:29

Any Suggestions!

D.B September 21, 2015 23:38

Quote:

Originally Posted by Mehar (Post 564958)
Any Suggestions!

Please describe your problem in detail, anyone can only help you if your are more clear about the domain, ( like what are blowing towers ?) Also define the primary aim of your design, as that will determine what parameters should be used for comparison

Mehar September 22, 2015 05:25

Quote:

Originally Posted by D.B (Post 565075)
Please describe your problem in detail, anyone can only help you if your are more clear about the domain, ( like what are blowing towers ?) Also define the primary aim of your design, as that will determine what parameters should be used for comparison

Thanks For Your Interest D.B!
I have shared domain image with my 1st post, but I think it was not visible (My bad), however, I am sharing it again.
The ultimate aim is to contain and collect anything(eg particulates or gases) coming out of the central structure, if there is a particulates or gaseous source in it. But for the time being, primary objective is to perform fundamental studies about finding;
1) How strong is the air curtain developed by blowing towers against free stream and how changing blowing tower speed, angle, flow rate etc would effect air curtain?
2) How flow close to rectangular structure is effected by above tweaking?

I can visualize and compare velocity,pressure etc with paraview, but its qualitative, I want some quantitative parameters, which can give answers to above questions and later on can be for design purposes.

Hope my explanation is clear!
Thanks


https://www.dropbox.com/s/5duhpxfmph...itled.jpg?dl=0

D.B September 22, 2015 07:24

Interesting problem indeed. As I interpret from what you have said, the important parameter should be collection efficiency. Now I think, you are just doing a simple CFD without any particles involved (?) But since you have mentioned about the basic aims of the studies as of now, I can suggest this :

1) What do you mean by strength of the air curtain ? It can be quantified in a number of ways, which ultimately depend on your aim for creating that curtain (in this case to trap the particles/gases). One measure can be the net reduction in drag on the tower due to the curtain, but this measure seems too generic and not optimal for your problem. You need to first get clarity on the final aim of the work, and then decide on the parameters you need to consider in a basic simulation or if even a basic simulation is good enough.
2) I think you are looking at point #2 to see how it will affect any flow coming out of the central tower, for that I think you should
a) have a flow source from the tower, if you don't already have one
b) Another thing you can do is to measure the thickness of the curtain created( maybe define it as till the velocity drops to 50% or some other fraction of the core velocity of the curtain) and quantify the ratio of distance between centre-line of core and the nearest tower edge to the curtain thickness and come up with studies to see which ratio might give you the best collection efficiency.

This is a medium-big ( BIG if its your PhD thesis topic ?) project and the things will have to be tried and tested to see which is the optimal measure and things might not be apparent from the beginning, read a lot of papers which have done something similar, even some papers on cyclone separators might help and come up with some parameters to judge how good is the design.

Quote:

Originally Posted by Mehar (Post 565114)
Thanks For Your Interest D.B!
The ultimate aim is to contain and collect anything(eg particulates or gases) coming out of the central structure, if there is a particulates or gaseous source in it. But for the time being, primary objective is to perform fundamental studies about finding;
1) How strong is the air curtain developed by blowing towers against free stream and how changing blowing tower speed, angle, flow rate etc would effect air curtain?
2) How flow close to rectangular structure is effected by above tweaking?

I can visualize and compare velocity,pressure etc with paraview, but its qualitative, I want some quantitative parameters, which can give answers to above questions and later on can be for design purposes.

Hope my explanation is clear!
Thanks


https://www.dropbox.com/s/5duhpxfmph...itled.jpg?dl=0



All times are GMT -4. The time now is 02:06.