The Bajulaz engine

[GregLocock]

Makes the usual claims for prototype novel engines, 50% efficiency in particular. So, who understands it? What is its weakness?

http://www.bajulazsa.com/Site/sixstroke.html

Cheers

Greg Locock

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[R1100S]

The surface area is huge, the compression ratio is low, and the amount of pumping working is increased. It is more complicated and expensive to produce.

 

[SomptingGuy]

Looks a bit like an IDI diesel. Would like to see some plots of BSFC etc.

 

[GregLocock]

The 'hot' intake valve would live a very exciting life.

Cheers

Greg Locock

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[BrianPetersen]

... and probably an exciting *short* life. Thermal losses through that valve will likely be enormous.

 

[franzh]

I see two additional crank revolutions and corresponding valve reactions for no additional power strokes. To me this is a net loss of efficiency. Adding heat to the intake air charge should also drop efficiency.

Franz

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[EdDanzer]

I don’t see how they can get the listed efficiency when they exhaust the burnt gasses. The heat stored in the metal components is what will be available for expansion during the sixth power stroke.

I’m sure the high temperature valve and guide would have to be special in order to live 150,000 miles without increasing pollution levels as will be required in the upcoming regulations.

Ed Danzer

http://www.danzcoinc.com

http://www.dehyds.com

 

[MikeHalloran]

I wish the animation had more frames.

I see a regular intake and exhaust valve on the right. That much I understand.

The unique part of the hardware is an annular air gap around the prechamber/remote chanber, with the connections between the cylinder and the annulus and between the cylinder and the chamber individually valved.

But I'm not understanding all of the valve timing/ injection timing and gas dynamics.



Mike Halloran
Pembroke Pines, FL, USA

 

[GregLocock]

Just as an addendum, I spent far too long thinking about this last night.

One other issue is that the dead space in the system is large, and the poppet valves will need further dead space in which to operate. This gives you permanent EGR.

Obviously power for a given bore stroke and rpm will at best be 2/3 that of a 4 stroke.

fmep will be higher by 50% as well.

My guess is that it would show better sfc at part load than a 4 stroke, if anywhere, but that at full load (ie 66%) it would not.

The valve life is the killer.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.