Achates Power Heavy Duty Diesel Program Review

Question

Achates Power Heavy Duty Diesel Program Review

RodRico (Automotive)

(OP)

14 Jun 21 18:24

Not a lot of detail, but more than I've seen anywhere else to date... https://youtu.be/Az16WAfzZbI

gruntguru (Mechanical) · Answer 1 · 2021-06-14 21:37:23

Impressive. The combination of 50% TE and ultra low emissions is unprecedented in an engine this size.
Seems Hugo Junkers was on the right track 100 years ago.

je suis charlie

enginesrus (Mechanical) · Answer 2 · 2021-06-15 04:24:14

Yes all the good old school stuff works great, nothing new in this design.

TugboatEng (Marine/Ocean) · Answer 3 · 2021-06-15 06:44:43

That's what they want you to believe, engines. They want their competition barking up the wrong tree.

gruntguru (Mechanical) · Answer 4 · 2021-06-15 21:10:38

The uniflow scavenged OP 2 stroke was always known to have numerous thermodynamic advantages.

According to Achates, they have discovered other ideal characteristics, in particular ready control of excess air and internal EGR. As a result, combined with modern external EGR, exhaust aftertreatment and turbo/mechanical supercharging/scavenging, Achates are achieving very good results across the emissions drive cycle with minimal compromise to TE (and therefore CO2).

je suis charlie

RodRico (Automotive) · Answer 5 · 2021-06-17 00:58:14

I heard they put a lot of work into oil control to overcome the tendency to shed oil out ports (a well known issue with opposed-piston two-strokes), but it turns out they weren't all that clever... at 57:50 in the video, they mention they're using "Oerlikon Likon spray bore coating" which sounds just like the technique used by Mann and Wärtsilä in their big marine engines.

TugboatEng (Marine/Ocean) · Answer 6 · 2021-06-17 04:42:48

Man and Wartsila have OP engines?

Are coated bores a band-aid?

RodRico (Automotive) · Answer 7 · 2021-06-17 16:52:21

Quote (TugboatEng)
Man and Wartsila have OP engines?

No, I got opposed-piston happy. It's been corrected.

Bore spray isn't a band-aid, it's just complex and seldom used in small engines AFAIK.
I thought Achates was injecting oil through micro-passages between the ports when the ports are open and letting the pistons drag it down the bore. That's what I do.

Interestingly, Volvo cut a patent in 2017 for an opposed piston. I wonder what they plan.
See https://worldwide.espacenet.com/patent/search/fami...

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Achates Power Heavy Duty Diesel Program Review