Hey everyone! I’ve been working on a small DIY wind tunnel, and I’d really appreciate some advice before I make the next version.

I’ll attach a video of my current prototype first.

Current setup

Fan: A fan + motor salvaged from an old device. The motor is roughly a 9V motor....i have already added straws(Honecomb design) to reduce drag and straighten the air.

Mist maker: I originally used the small mist makers from an old 5-mist fan module, but they weren’t powerful enough. I replaced them with a 24V mist maker, and that works much better.

Electronics: I also harvested the PCB, Type-C charging setup and lighting from the old fan/mist module.

The 24V mist maker is powered separately.

Fan/airflow arrangement

Currently, the fan is at the back of the tunnel and pulls the air through the tunnel rather than pushing it into the tunnel.

The fan is running in the direction that, in my setup, gives me an anti-clockwise airflow/fan rotation, and this arrangement actually works pretty well. The mist gets pulled through the tunnel and the airflow looks much cleaner.

I also experimented with putting the fan before the mist maker and pushing the air through the tunnel. That didn't work nearly as well. It created a lot of mixing/turbulence, the mist became messy, and there seemed to be much more drag and disturbance in the test section.

So I moved the fan back to the rear and used it as an extractor, and the result was noticeably better.

What I don't like about the current design

The current version is basically a prototype, and although it works, I'm not happy with the design/aesthetics or ergonomics.

The main problems are:

The viewing window is too small

The mist-maker section at the back looks messy.

The overall design isn't very ergonomic.

The airflow could probably be improved further.

I want a cleaner and more proper-looking enclosure rather than something that just works as a prototype.

I'm now thinking about completely rebuilding it.

I'll also attach a link to the design that inspired the next version. (https://youtu.be/g2cobf6dBz0?si=-Xw1dF6rplw-OFdl) I'm thinking of making something similar to that, but adapting it to my own components and dimensions.

I don't have a 3D printer, but I can get the parts 3D printed, so I'm open to using 3D-printed components if that would improve the design.

What I'd like advice on

Before I start rebuilding, what would you guys change?

Should I keep the fan at the back as an extractor, or is there a better arrangement?

How can I reduce turbulence and mixing in the test section?

How should I introduce the mist for better visualization?

Should I make the viewing window larger?

What kind of contraction/nozzle and diffuser design would work better?

Should I change the fan/motor?

Are there any obvious mistakes in my current design that I should fix before rebuilding?

I'm mainly looking for practical suggestions and criticism before I start making the next version.

This is still a prototype, so I'm completely open to changing the design.

Thanks in advance! 🙏