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Internal Combustion Engine (2021)

ciechanow.ski

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Re: Internal Combustion Engine (2021)

#71

Post by Sohcahtoa82 »

zuzululu wrote: post #63
Sohcahtoa82 wrote: post #58

Earlier quoted context omitted.

The carbon footprint of producing an EV is higher than an ICE. Nobody disputes that. But the lower carbon footprint of operating the an EV makes the EV have a lower footprint over the life of the vehicle. This is true even if your electricity comes purely from coal, as a coal power plant gets an economy of scale that an ICE doesn't achieve. If your power comes from a renewable source, then the trade-off happens even…

the problem is where these lithiums are sourced from and that raises the costs of human rights

Questioning the lithium source is valid, but also a red herring when we're talking about environmental impact.

But yes, battery minerals can involve human rights abuses. But ICE vehicles are also built from steel, aluminum, copper, rubber, electronics, and metals that can involve forced labor, unsafe mining, land displacement, pollution, or exploitative labor. The ethical issue is supply chain due diligence across the whole auto industry, not just lithium.

Funny how some people (Mostly anti-EV folks) only discover supply chain ethics only when the car has a battery.

Re: Internal Combustion Engine (2021)

#72

Post by dotancohen »

calmbonsai wrote: post #24
WalterBright wrote: post #17

Earlier quoted context omitted.

That's the point of all uses of oil, other than rust prevention.

Some engines are also substantially cooled by oil, but those are either older designs (think “air-cooled” Porche) or industrial prime-movers.

Some engines, especially high mileage engines from Detroit, are also substantially fueled by oil. In a sense.

Re: Internal Combustion Engine (2021)

#73

Post by dotancohen »

nablaone wrote: post #33
WalterBright wrote: post #27

Earlier quoted context omitted.

You are quite right, the oil also serves to transport the heat away.

It's a solvent also.

Oil also keeps the gaskets (e.g. valve cover gasket, water pump) and seals (front and rear mains) pliable.

Re: Internal Combustion Engine (2021)

#74

Post by TacticalCoder »

OptionOfT wrote: post #65
londons_explore wrote: post #25

Worth noting the design of the internal combustion engine hasn't changed much in 50 years. The thing that has changed is the control systems. What used to be a primitive mechanical way of mixing fuel and air (the carburettor), is now an electronic fuel injection system, with the fuel air ratio very carefully matched to reduce pollution (fun fact: modern cars release so little carbon monoxide, you won't kill yourself…

What I am surprised by is that cams are still used to operate the valves. Given to how precise these need to be these days, I would've guessed they would've switched to electronically actuated valves.

> What I am surprised by is that cams are still used to operate the valves.

Kinda, it's all continuous variable valve lift now:

https://en.wikipedia.org/wiki/Variable_valve_lift

Re: Internal Combustion Engine (2021)

#75

Post by userbinator »

MarkusWandel wrote: post #12

Wonderful but it irritates me that so many descriptions of internal combustion engines refer to "explosions" of the fuel. You don't want that. It causes knocking and pinging and engine damage. You want a controlled burn that generates heat smoothly.

There are videos on YouTube of what the combustion actually looks like in slow motion. It's fast, but far less violent than an "explosion".

Re: Internal Combustion Engine (2021)

#76

Post by userbinator »

While they look perfectly round, piston skirts are actually slightly oval.

...something which has been the case for at least 80 years:

https://news.ycombinator.com/item?id=15397926 (the article in that link has now moved to https://www.web.imperialclub.info/Repair/Lit/Master/003/inde... )

Re: Internal Combustion Engine (2021)

#78

Post by yunnpp »

plasticeagle wrote: post #66

Who is this person. A beautifully written and illustrated explanation of a fascinating machine. A website filled with other explanations of other things, also wonderfully written and clearly explained. An instagram filled with beautiful landscape photographs, an "X" page consisting only of links back to this blog, and a Patreon with hardly any more information that that. I love this. Fantastic content. Zero ego. And…

There is no AI use here. I'm somewhat offended by the suggestion even though I have no relation to the author. Bartosz has been shredding for a long time now. His javascript is also unminified and perfectly readable, making it a great reference for study despite not being advertised on his pages. The animations are all hand-made. The guy is cooking. To suggest that any of it is AI is an utter blasphemy. AI is for noobs, grifters, and low-effort content farmers and Bartosz isn't any of those things.

Re: Internal Combustion Engine (2021)

#79

Post by left-struck »

OptionOfT wrote: post #65
londons_explore wrote: post #25

Worth noting the design of the internal combustion engine hasn't changed much in 50 years. The thing that has changed is the control systems. What used to be a primitive mechanical way of mixing fuel and air (the carburettor), is now an electronic fuel injection system, with the fuel air ratio very carefully matched to reduce pollution (fun fact: modern cars release so little carbon monoxide, you won't kill yourself…

What I am surprised by is that cams are still used to operate the valves. Given to how precise these need to be these days, I would've guessed they would've switched to electronically actuated valves.

It’s because of the good enough precision at low cost that we use cams, it’s extremely difficult to get precise movement and the forces and speeds required when an engine is operating at >5000 rpm. It’s not impossible but the trade offs are rarely worth.

The exact valve timing isn’t really a big factor in emissions as much as temperature control and exact AFR control. I mean valves need precise timing to avoid coming into contact with pistons but if you’re already at that level of precision then you gaining more precision won’t really reduce your emissions.

Of course being able to change the timing of your valves helps with both efficiency and emissions, but VVT does that pretty well.

Re: Internal Combustion Engine (2021)

#80

Post by left-struck »

londons_explore wrote: post #25

Worth noting the design of the internal combustion engine hasn't changed much in 50 years. The thing that has changed is the control systems. What used to be a primitive mechanical way of mixing fuel and air (the carburettor), is now an electronic fuel injection system, with the fuel air ratio very carefully matched to reduce pollution (fun fact: modern cars release so little carbon monoxide, you won't kill yourself…

> fun fact: modern cars release so little carbon monoxide, you won't kill yourself by starting one in a garage

Modern cars still release as much CO2 as older cars… which is still incompatible with human respiration.

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