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Struggling to select the right fin geometry and material, any tips ?

Hey folks, I'm working on a project involving the design of a heat exchanger, and I've hit a bit of a wall. I'm trying to optimize the fin design for maximum thermal efficiency while keeping the pressure drop within acceptable limits. I know the general principles, but I'm struggling with the specifics of selecting the right fin geometry and material.

Any tips or resources you could recommend for tackling this?

Appreciate any advice from those who've been down this road before!

4 comments

j4k3

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Probably way beneath the level you're looking for, as I'm no engineer, but when I've been designing stuff for 3d printing and Maker projects, the only practical info I've found is by searching for HVAC design guides on places like YouTube. When it comes to turbulent flow, that was the only source I could find with rules of thumb and people that are willing to talk about useful information. CFD is full of spam and baiting tactics trying to sell some software, consulting, gold gilded book, or classes.

Achugodblessme

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💯 I have worked with some really seasoned engineers for the past twenty-five years, and what you said right here, its almost like you just took the words right out of their mouths.

Fucking spot on

Kevin

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Thanks for the response! Every bit of info helps, so no worries if it's not exactly what I'm looking for. HVAC design guides on YouTube might actually be a good starting point for understanding some practical design principles. I hadn't considered that angle before.

And yeah, I totally get what you mean about CFD being a minefield of spam and sales pitches. It’s frustrating trying to wade through all that just to find some solid advice.

Appreciate the tip—I'll check out those HVAC guides and see if I can apply any of their insights to my project. If you come across any other resources or have more suggestions, feel free to share!

j4k3

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If you're doing practical design, it is hard to beat empirical observation. While you could get crazy with test setups, it is not necessary.

a bright lighting setup will allow you to capture maximum frame rates, even with your phone.
think about your background and use anything you have on hand like a black tee-shirt, but think about contrast. Most cameras use a point of sharp contrast to focus, so setup with this in mind.
ideally, use a vape pen as your smoke machine. These make an ideal dense smoke source for cheap. Alternatively, an ultrasonic fog setup can do some very small scale stuff, but is a joke next to a vape pen setup.
if you can duct air in a way that partially restricts flow to a fan, you can use the voltage or the RPM to determine how iterations compare to each other without an expensive qualified measurement tool or calibration.

That's what I messed around with when designing and comparing various 3d printer tool head duct designs for part cooling.