Combustion engine web-based simulator

https://combustionlab.net

by mytuny • 17 days ago

235 80 17 days ago

combustionlab.net

BeefySwain• 12 days ago

Am I missing something? Setting the throttle to 0% seems to do nothing?

snug• 12 days ago

All the gauges on the top right except the RPMs move

chris_money202• 12 days ago

"How it Works" -> "Idk" OP probably

monkellipse• 12 days ago

I see no declaration that this is a machine generated site, but the aesthetic is a dead giveaway. The language on the “how it works” page is unmistakably LLM output. As a total novice in engines this site had the potential to educate me, but did the author vet the data at all? If the author doesn’t bother telling me they checked any output on this, what assurance do I have anything is accurate on the site at all? If I knew an actual engineer put their focus on this tool I’d feel much better about trying to learn something from it. Short of that it’s just a pretty (but predictable) interface.

btrettel• 12 days ago

I'm a mechanical engineer who has written similar tools for work and hobbies. Producing pretty pictures does not mean that the model is physically accurate. Unfortunately, such tools seem be evaluated much more on flashiness and not on more reliable and objective criteria like physical accuracy based on verification and validation test suites. I'm seeing that in the comments here. I don't think LLMs make what I do irrelevant, but I have thought that I'm going to have to improve how flashy my simulations look to compete better with non-experts who use LLMs.

Waterluvian• 12 days ago

The aesthetic is what I get any time I ask for something UI-like in Claude. But gosh darn it I like the look.

Geee3• 12 days ago

3638 kW / 4878 hp is the most powerful engine I could build with this.

jstanley3• 12 days ago

How do you tell how much power it is making?

Geee3• 12 days ago

On the dyno panel you see "pk" which is peak power. If you don't see the dyno panel on the right, you'll have to scroll down to see it.

CrimsonRain• 12 days ago

3765 kW / 5049 hp is the max I could do.

V Twin Bank, Turbocharged with Intercooler. And Fuel is Hydrogen!

Geee3• 12 days ago

I was using Supercharged, thought that was better. :) Now I got it tuned up to 3767 kW / 5051 hp, that must be the maximum.

jandrese2• 12 days ago

I imagine such an engine would instantly blow itself apart in real life. Basically the simulated version of those tractor pull cars where the engine survives for about 500 rotations before it has to be rebuilt.

userbinator4• 12 days ago

Depends on the displacement and other factors. Huge engines in that power range like the https://en.wikipedia.org/wiki/EMD_710 are used in locomotives and other applications like power generation where they run 24/7 at 100% load.

quantumHazer• 12 days ago

Probably llm slop

zuzululu5• 12 days ago

if its useful and entertaining i dont think many ppl care especially evident that you cannot be certain with your accusations

jenniferhooley3• 12 days ago

How is it useful? I'm no expert in combustion engines, so I'd hesitate to rely on a slop graphic like this to learn about them as I doubt the creator has any idea about them either.

It's like a friend - he was like "Look at this awesome set of categorized interactive animations from claude to learn geometry!".

And like 60% of the animations were technically just wrong. Very pretty though, and the effects were cute... I guess...?

Retr0id• 12 days ago

I'm certain.

perssontm• 12 days ago

I was hoping for a two stroke mode as well!

bwestergard• 12 days ago

I don't understand how the throttle and RPM can be modified independently. Surely the RPM depends on the throttle?

jstanley3• 12 days ago

In principle you can instantaneously set the throttle opening to some position and set the RPM to whatever you want. In time the RPM will rise or fall until the engine is at equilibrium, but throttle position and RPM aren't like mechanically interlocked. Otherwise how could the engine speed up when you go down a hill?

mikestorrent2• 12 days ago

When you press the gas pedal in your car down (which used to just be a cable to the throttle body), does your car instantaneously increase in speed to match the pedal position?

All you're doing is letting more air in - the RPM is a function of the power the engine generates; more fuel and air than is currently needed for the current load at the current speed = increasing RPMs.

If you put the clutch in, a little blip of the gas is all that's needed to get the RPM quite high very quickly. The moment there's load on there, the same blip will not do very much at all.

jandrese2• 12 days ago

Imagine your vehicle is pulling a heavy load up a hill vs. going flat out on a track. Your throttle position may be the same but the RPMs are likely to be quite different, even when you account for the transmission.

topspin• 12 days ago

Surely the RPM depends on the throttle?

Partly. Another factor in the equation is load.

amaze_28• 12 days ago

this is really impressive. actual movements with live diagrams looks great. you can consider adding sound to take it to another level.

seafisher• 12 days ago

really interesting project - would be good to see a link to a repo

Lwerewolf• 12 days ago

187 N/A BSFC @ 2000rpm and open throttle. Tried emulating a DI 2GR-FXE. Seems a bit optimistic, but still fun to play with.

kristiandupont• 12 days ago

Very nice! Reminds of this classic, focused mostly on the sounds: https://github.com/ange-yaghi/engine-sim

huydotnet• 12 days ago

If you're looking for a carefully crafted/written work to explain internal combustion engines, look no further than this one https://ciechanow.ski/internal-combustion-engine/ (the Mechanical Watch article from the same author was featured on HN a while ago).

boppo1• 12 days ago

I wish he was still making posts.

aosaigh• 12 days ago

He isn't? What happened?

askvictor• 12 days ago

It's been a year and a half since the last one, compared to 1 or 2 posts per year. Here's hoping he's taking some extra time to make something amazing

IshKebab• 12 days ago

How can I instantly tell this is slop?

lwansbrough2• 12 days ago

- //

- letter spacing

butlike2• 12 days ago

So if I set the animation speed to 1:1 and set the RPM to 3000, that's what it would look like inside the engine when I'm ready to shift gears? Seems WAY faster than what I expected in real life

mikestorrent2• 12 days ago

3000? Here I am wishing there was some Wankel Rotary representation and you're shifting at 3000? What are you driving, a Peterbilt?

butlike2• 9 days ago

I might be confused here. In the manual car I drive, I shift when the tachometer says 3, which I understand it as being 3000 RPMs?

brotchie• 12 days ago

3000 RPM is 50Hz right?

steve918• 12 days ago

Calling this AI slop would be generous. If we made a list of the things wrong with it we would be here all day. Nothing has an effect on redline RPM, you can create compression and turbo combos that would instantly grenade an engine, the preset “super car” has 200hp?

The only thing it illustrates is the authors lack of understanding.

minusLik• 11 days ago

I fed the technical data of my motorcycle into the model and it told me right away that this build would destroy a real engine because the piston speed would be too great.

The real thing has been running for 56,000 miles, so it can't be that bad. *g

leetbulb• 11 days ago

"Supercar" has 670hp 500lb-ft @ 5297rpm which seems reasonable. After configuring the tool with my car's specs, it was fairly close on the dyno; though, I'm very far from an expert. Imho, pretty cool, nonetheless.

all22• 12 days ago

@AngeTheGreat on youtube is worth mentioning here, I think.

He has a whole series on building out engine simulators of various types, and even published a Steam game for steam engine simulation.

His work is notable because he leans heavily into generating sound directly from the simulations.

suprjami• 12 days ago

Yes, seriously everyone should watch this:

https://www.youtube.com/@AngeTheGreat

Other engine simulators work by approximating the engine.

Ange's engine simulator works by approximating physics of air fluid dynamics through a combustion chamber and exhaust, sound propagation, etc and then putting an engine into that simulation.

It's incredible how productive and precise he is.

CobrastanJorji• 12 days ago

Absolutely insane.

Also, I love that it was open sourced. Although it sounds like from the GitHub page summary that there was some shenanigans involving a "certain very high profile game studio" that I'd love to hear more tea about.

LoganDark3• 12 days ago

He published it as open-source for like 5 seconds before taking the repository down in order to charge for it on Steam! I'm a little weirded out by that pattern of open-sourcing it and then just changing his mind.

onestay42• 12 days ago

I think what happened was that it became his full time job, and he started to need to be able to make money from it. At least, that's what I remember; I haven't seen much about it as of late.

leetrout• 11 days ago

I have a podcast interview with Ange where we talk a bit about the first time this blew up on HN

https://music.youtube.com/watch?v=bi6bLSCnjcY&si=r4atSKfsBEQ...

lwansbrough2• 12 days ago

From the pre-slop era: https://www.youtube.com/watch?v=RKT-sKtR970

glouwbug• 12 days ago

Gave it my own spin once: https://github.com/glouw/ensim4

Makes audio too

burnt_toast• 12 days ago

Nice little project, I inputted the dimensions of a engine I've been building (b20-vtec) and it estimated 160whp which sounds low but I also can't set up my cams properly because it looks like this was designed for SOHC engines.

Very cool either way.

mtr• 12 days ago

Exhaust temp increase with decreasing lambda, and peaks at 0.7 lambda. That part of the model is likely incorrect.

zuzululu5• 12 days ago

would be awesome if it could generate sounds like how lfs does it

deadcatfound• 12 days ago

Sounds would be pretty cool.

noefingway• 12 days ago

So i'll throw this out there. When I was a growing up back in the 50's (yeah, way back then) I was given a model of a v-8 engine to build. It was clear plastic, had pistons, crankshaft, valves, and little red lights for the spark plugs. Small battery powered motor (I think in the starter motor) made everything go round and rounds. One of the coolest models I ever built as a kid.

dmwood• 12 days ago

This was the Revell 'Visible V8', first released in 1958. https://macsmotorcitygarage.com/revisiting-the-visible-v8/

userbinator4• 12 days ago

While fairly realistic in function, the Visible V8 is not a replica of a specific production engine, though it most resembles an early Cadillac or Studebaker V8.

...but that transmission definitely looks like the early 4-speed Hydramatic: http://www.1954advance-design.com/Hydra-Matic-rebuild/index....

JackFr• 12 days ago

The Visible V-8. That made it well into the 70s.

userbinator4• 12 days ago

They're still making that model today.

AtomicOrbital• 12 days ago

we have all heard of V8 ... now visualize a W12

... two pairs of V3 in a Bentley

goodmythical• 12 days ago

Airplanes do (did?) v16s and v24s as well, if memory serves.

There's also a build out there where someone did a "v12" vw beetle with a v6 for each axle.

ranger_danger• 11 days ago

Don't the Veyron/Chiron have a W16?

yunnpp• 12 days ago

I am genuinely curious why OP thinks this slop post should be of interest to others. Nobody cares how you're prompting an LLM, guys.

FrostKiwi• 12 days ago

Interesting, I had Fable generate me a summary using an identical style, with the same square design, bg and yellow highlights

other_herbert• 12 days ago

I had just been daydreaming about a v12 with tiny pistons and wondering how that would behave … now I can find out … turns out it would be terrible at low speed

userbinator4• 12 days ago

Why have a kW/Nm - HP/lbf setting, but no metric/US option for the bore and stroke?

Others here are suspicious of the numbers, but at least for the actual engine in my daily driver which I've dyno'd before, it seems reasonable with around 400HP and 450lbf for a 400ci NA V8.

jdw64• 12 days ago

If LLMs had come out when I was younger, I would have been able to understand things this easily. There are some incorrect implementations, but they're incredibly helpful for grasping the concepts.

h2aichat• 11 days ago

I like It, no matter what

mwexler• 11 days ago

I wish this had a stepper so I could see how things change at each point in the cycle. But even without, quite cool to play with.

lohith1710• 11 days ago

Whether it's AI generated or not. It's pretty cool for beginners. Only issue is there would be a problem if we think this is how real engines work as there would be lot of tweaks.

Combustion engine web-based simulator

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