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Comment by Toutouxc | original | Internal Combustion Engine (2021)
[−]Toutouxc · 2026-07-01 Wed 18:07 UTC · link
Not exactly. You do want a deflagration and not a detonation, but "explosion" is more loosely defined and, depending on who you're talking to, a self-sustaining subsonic flame front and a sharp pressure spike are a perfectly valid explosion.
[−]raffael_de · 2026-07-01 Wed 19:20 UTC · link
explosion/detonation causes engine knocking or pre-ignition which is both very bad. a properly working combustion engine is driven by controlled burning.
[−]Toutouxc · 2026-07-01 Wed 19:56 UTC · link
You’re replying to a post that says that “explosion” doesn’t imply “detonation”.
[−]raffael_de · 2026-07-01 Wed 21:10 UTC · link
and that is not strictly correct. it's called combustion engine and not explosion engine for a reason.
[−]kube-system · 2026-07-02 Thu 05:42 UTC · link
But it is strictly correct. Deflagration is the definition of low (i.e. subsonic) explosive.

Combustion is a broader term — combustion just refers to burning. And the reason it is called an internal combustion engine is to contrast it from its predecessor combustion engine designs - the external combustion engine.

More precisely, the type of combustion happening in an ICE engine is (low) explosive.

https://en.wikipedia.org/wiki/Explosive#Low