Diffuser design

Anything aero-related (wings, under-trays) etc. Separate from "Wind Management", which deals with protection from wind buffeting.
Midlana1
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Diffuser design

Postby Midlana1 » 17 May 2018, 11:22

This article is very educational for explaining what they are and how they work, http://www.trackcarperformance.com/2017/08/willem-toet-explains-motorsport-diffusers/. Most online discussions about diffuser design are completely wrong.

This was found when searching for the answer to: is a flat (fixed angle) diffuser more effective than a gradually increasing (curved) diffuser? Seems that only flat-plate designs are discussed in both this and the other article below.

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Re: Diffuser design

Postby Midlana1 » 17 May 2018, 15:05

A very helpful article by Simon McBeath, which starts on page 56.
http://porschecarshistory.com/wp-content/old/lib/magazines/RE/2014/RE2014-10.pdf

I realize the ground clearances involved in these examples are on the order of 50mm/2", but it's still very educational.

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Re: Diffuser design

Postby Midlana1 » 04 Jun 2018, 10:05

I posted these to my blog but are being added here for completeness. The diffuser is a 24" x 48" aluminum panel, stiffened with angle aluminum.

Image

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Image

Image

Image

Note the last picture, showing the melted fin after just one test drive and my too-smart-for-my-own-good decision to go with HDPE for the vertical fins... They're being replaced with aluminum. Really though, plastic is the right material; I just don't know what material would be correct. It's unknown how hot it gets at the exhaust outlet and honestly, I don't feel real motivated to measure it. As a result, I thought that with plenty of air rushing by, the plastic would be fine - oops. Separately, the exhaust will be trimmed flush, mostly for aesthetics, but also to help air flow.

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Re: Diffuser design

Postby Castrol » 05 Jun 2018, 15:04

Keep the updates going! I haven’t seen a lot of action on the forum since I started following about 3 weeks ago, but even though I’m not yet ready to start my build, reading what others are doing is awesome. Keep it up!!!


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