Common HPA nozzles performances repository

Hi, OpenAg community!
In the past few weeks, my concept for a small size grow box has evolved from soakaponic to proper HPA, thanks in great part to this forum and its members’ experiences and insights.

The trickiest part of the planning seems to be the selection and setup of the nozzles. I’ve seen countless builds that, while operating at high pressure and with proper nozzles, uses way too many nozzles to achieve the proposed “1mL per 100L root chamber volume”, even with ridiculously short spraying timings.

I get where true HPA can be misleading, even for a seasoned grower. We’re drying out entire rivers to water crops, while here the plan is to pretty much have them run on air. That’s part of the beauty of this system.

Other threads touched the subject in the past, but I believe that a proper repository of true and tested nozzles and real performances reports should help make the whole process more deterministic.
On top of that, info regarding the nozzles are also overlooked in most BOMs or build guides, even if these are, probably, among the most important ones.

While I do understand that there are countless variables, I believe we will all end up running in comparable conditions (no draft in root chambers, similar fluid temps, viscosity and surface tensions) as plants are the performance benchmark for our systems and they can be fairly picky in terms of conditions they thrive in.

Most likely, the major source of variables here is related to the “piping”. But even then, barring major issues causing serious loss of pressure/flow, most results should be comparable (please, correct me if I am mistaken) between slightly different setups and real outlier would be easily identified.
We might end up creating a basic “nozzle testing guideline”, to sidestep major build related variables.

The goal is to establish a baseline of nozzles performances to aid chambers designs. Right now I bet I’m not alone in being unable to “visualize” how the spray pattern will turn out to be.

I took the freedom to create this spreadsheet. It is openly editable by users with the link (this setting can be restricted as needed).

Please, have a look at the spreadsheet, let me know if it should be edited (to add/remove columns or clarify something) and what do you think about the whole idea.

Would be great if it could be populated with a good number of different nozzles models and even more performance data.

Sorry for the hugely long first post. Hopefully, my idea is sound and doesn’t turn out wasting everybody’s time :slight_smile:

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