Which of the black triangles produce less drag?

which of the black triangles produce less drag?

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God fucking damn.

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it's not laziness it's human ingenuity

also, is ellipse, the one i get for just squashing a circle in paint one of the most aerodynamic shapes there is?

Human ingenuity would be finding the font used, moving the rest of the sentence to the left and then typing the letter s using the font so that it doesn't look hideous.

Also,I don't know shit about physics boi.

top

is that shit handdrawn?

no

Bottom. The air approaching the sharp corners may have a chance of staying laminar if the Reynolds number is low enough (see flow around a square) however for the top one, flow coming off a sharp corner always results in eddy currents.

Complete misunderstanding of aerodynamics here.

This guy has it right.

Could you demonstrate this by making a cone and dropping it through air to see how it orients itself?

>tfw self taught RC aircraft enthusiast
I feel all warm and fuzzy inside. I'm actually going to start a mech eng degree in a month however, take my passion further. Good to know that I taught myself correctly.

I understood nothing of what you just said, but I have the desire to increase my intelligence in various subjects. How can i learn what you know? Classes, books, etc

"Knowledge" not "intelligence"
You can use MIT courses
ocw.mit.edu/index.htm
And if you have problems with English words I suggest you to search on Facebook some engineering groups from your country. At least you have some material in your native language

They aren't the same thing but are synonymous. Is it that wrong to use them interchangeably?

Less drag force: bottom

Less net resistive force: Top

Knowledge is the collection of skills and information a person has acquired through experience. Intelligence is the ability to apply knowledge

lol moron

Oh.
Thanks user. I was born here(US) and English is my first language but I guess my evident lack of knowledge is why I want & need to learn more.
Good luck with what you're doing.

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Thank you and good luck you too.
Never stop learning

It really doesn't take a rocket scientist to answer OPs question.
Actually i imagine that a person who cannot answer this question has ultimately lost his connection to the real world.

No. Form drag is far greater than skin drag

RC guy here. I just picked up a copy of "fluid mechanics for dummies" from my library no joke. I didn't understand most of the maths but the concepts I could follow.
I am not

No sorry "fluid mechanics demystified"

Obviously depends on the fluid properties, speed and surface properties.

If that's room temp 1 bar atmosphere it's obviously the top arrow.

Top, given enough time.

Ever looked at a missile, rocket, aircraft, bullet? All of them were invented in the past. Past inventions improve over time and after an amount of time the shape will rotate 180 due to an amount of periodic changes, as inventions are given periodic changes over an amount of time (see spoken language (black African languages improved with the 180 skin tone of white European language)).

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I would say the top one produces less drag as it is sorta a bullet

Source? Neither Google nor TinEye give me anything and iqdb only gives hentai.

>2min in photoshop
The terms for the shapes should be correct

just google "rocket nose cone design" it is one of the pics that comes up, to my knowledge it is atleast mostly true.

That picture is false. The circle is obviously way bigger in cross section than the airfoil

> I don't know whay C_d is

>air moving at 100 km/h

L2Read

Hi /k/! Just here to tell you bc != cd, or even 1/cd for that matter! Oh wait... /k/ doesn't understand bc either. Never mind.

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the upper

The top one. The bottom one not only faces the full momentum of the free stream, the resulting upward velocity at the edge almost guarantees flow separation in the rest of the wedge.

If these were cars, I'd much rather drive behind the top one.

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what did he meme by this

bump

I gotta check out iqdb more often!

The lower black triangle.

Bottom

Looks more like how an airfoil is supposed to look
Less head on surface area

The wedged shape at the bottom does jackshit in this situation, so the top one

>being this autistic.

top is better for any supersonic flow while bottom is better for subsonic and transonic flow.
top will have greater form drag as boundry layer seperation hits a point of stagnation and reverses at the end causing low pressure behind to drag it back in a subsonic flow, but the tip is needed to cut through a pressure wave to reduce wave drag when going supersonic.

skin drag being negligible of course

>100 kmh
>supersonic
You just learnt about the Prandtl–Meyer function didn't you

>not reading the rest of the sentence.
you just learnt about clauses didn't you

>not reading the rest of the sentence.
I did, but supersonic flow is completely irrelevant so i wondered why you brought it up

meh. probably would have made sense not to but reading some of these comments shows
that people are not making that distinction when they talk about missiles, bullets, or planes.
>also Reynolds number

>also Reynolds number
Yeah, that's a big one. It can be any number depending on the size