Dust Collection Pressure-Flow Calculation Program

[Jim Becker]

Opening up the ports is indeed an involved task and with many "more modern" machines, there's internal duct/hose that plays into the equation. I think that it's too bad that the defacto standard for so many machines is 4" whereas 5"/120mm is a better average for good air flow performance, especially for machines with larger capacities which is a lot more common now, even in small shops. And yes, 6"/150mm can really rock on the larger machines for sure. But "back in the day", dust collectors were a new thing and I guess 4" got the nod, at least in North America, and it's continued to stick. Oh, well...

[Thomas Wilson]

I have placed Dustcollector&DuctBranch dot pdf in my shared folder of Google Drive. I hope this is a link. This is the text of the matlab model file for a single branch. Someone please try the link to see if it opens of an 8 page file of Matlab coding. It should be readable.

https://drive.google.com/drive/folde...Cg&usp=sharing

This is the matlab .m file that could be executed if loaded into Matlab.
https://drive.google.com/drive/folde...Cg&usp=sharing

I am fully aware that this is not easy to follow. I hope to have time to write up and explanation of the calculation soon.

[Chris Parks]

I have placed Dustcollector&DuctBranch dot pdf in my shared folder of Google Drive. I hope this is a link. This is the text of the matlab model file for a single branch. Someone please try the link to see if it opens of an 8 page file of Matlab coding. It should be readable.

https://drive.google.com/drive/folde...Cg&usp=sharing

This is the matlab .m file that could be executed if loaded into Matlab.
https://drive.google.com/drive/folde...Cg&usp=sharing

I am fully aware that this is not easy to follow. I hope to have time to write up and explanation of the calculation soon.

Thomas, I mean no criticism of your efforts with this question, how would someone shopping for a DE use this information to their advantage?

[Thomas Wilson]

I used it for evaluating minimum velocity in my system to determine in my old 2hp portable collector could be used as fixed collector for the whole shop. It was marginal. I upgraded to 5 hp.

There are lots of design comparisons you could make. Just about any what-if question that you might ask can be answered.

[Ole Anderson]

This discussion reminds me of when I designed my dust collection system in 2011, I made good use of the Excel program for duct losses that Bill Pentz had in his dust collection website. Website its still there but the link to the Excel program seems to be missing. It helped that I had a background in civil engineering and spent a lot of time with water flow modelling. Happy to use his calculator as I was not interested in re-inventing the wheel. A lot of good information there, but as in all things, you need to not take everything as a truism. https://www.billpentz.com/woodworkin...g_introduction