Volvo WAVE piston (for diesel)

[Steven]

I came across this truck engine development from Volvo, thought it might be interesting.
http://www.prnewswire.com/news-releases ... 77411.html
https://www.volvotrucks.ca/en-ca/about- ... upertruck/

Despite the fact that the internal combustion engine has been in existence for 140 years, during which time it has undergone continuous development, it still offers scope for improvement.

Jan Eismark and his colleague Michael Balthasar came up with the new wave design, which has now been patented. However, cutting-edge technology was needed to prove that their initial ideas were correct and to determine the exact design of the piston crown. This entailed using computational fluid dynamics (CFD) and filming the combustion process inside the cylinder at high speed.

In the case of a standard piston, the injector is located at the top of the cylinder and the fuel is sprayed toward the sides of the cylinder through a number of orifices in the injector. The combination of heat and pressure causes the fuel to ignite before it reaches the cylinder wall.

The flame hits the wall of the combustion chamber at a speed of up to 50 meters per second, spreads along the piston bowl wall and then collides with adjacent flames at an angle of 180 degrees, while still traveling at a high speed.

[J.A.W.]

Interesting Steven ta..
& the design almost presents as the inverse application of the much derided 'Singh grooves'..
..which are cut into the cylinder head/combustion chamber ..

[Edis]

Interesting Steven ta..
& the design almost presents as the inverse application of the much derided 'Singh grooves'..
..which are cut into the cylinder head/combustion chamber ..

This is nothing at all like 'Singh grooves'.

The purpose with this design is to increase late cycle soot oxidation for a direct injected diesel engine by changing how the "jet" from each injector nozzle collide with the piston bowl wall. To meet new NOx emissions requirements lower temperatures and higher EGR rates are required, this unfortunately reduce soot oxidation. This piston design increase soot oxidation by avoiding the creation of "stagnant zones" between the jets, after they have collided with the piston bowl wall.

[J.A.W.]

Interesting Steven ta..
& the design almost presents as the inverse application of the much derided 'Singh grooves'..
..which are cut into the cylinder head/combustion chamber ..

This is nothing at all like 'Singh grooves'.

The purpose with this design is to increase late cycle soot oxidation for a direct injected diesel engine by changing how the "jet" from each injector nozzle collide with the piston bowl wall. To meet new NOx emissions requirements lower temperatures and higher EGR rates are required, this unfortunately reduce soot oxidation. This piston design increase soot oxidation by avoiding the creation of "stagnant zones" between the jets, after they have collided with the piston bowl wall.

If you cannot perceive it..
I'd suggest you have a closer look.. since - its quite clearly.. the same concept.. 'cept in 'bas-relief' form..

[Edis]

Interesting Steven ta..
& the design almost presents as the inverse application of the much derided 'Singh grooves'..
..which are cut into the cylinder head/combustion chamber ..

This is nothing at all like 'Singh grooves'.

The purpose with this design is to increase late cycle soot oxidation for a direct injected diesel engine by changing how the "jet" from each injector nozzle collide with the piston bowl wall. To meet new NOx emissions requirements lower temperatures and higher EGR rates are required, this unfortunately reduce soot oxidation. This piston design increase soot oxidation by avoiding the creation of "stagnant zones" between the jets, after they have collided with the piston bowl wall.

If you cannot perceive it..
I'd suggest you have a closer look.. since - its quite clearly.. the same concept.. 'cept in 'bas-relief' form..

http://www.richstaylordporting.com/imag ... Head_2.jpg

Not at all the same concept. The wave-design is specific for diesel engine combustion, and can not be used in a spark ignition engine.

[PlatinumZealot]

I think Ray Charles can tell they are different by feeling them. The wave piston has clear undulations in the bowl, the other one is just a bunch of small ridges. I can't imagine the small ridges influencing the flow in as big a way as the wave.

[J.A.W.]

I think Ray Charles can tell they are different by feeling them. The wave piston has clear undulations in the bowl, the other one is just a bunch of small ridges. I can't imagine the small ridges influencing the flow in as big a way as the wave.

'Grasping at straws'?

Even 'Blind Freddy' can see the "concept" of a geometrically directed gas jet flow path in the combustion chamber..
..whether by channels let into the head, or the obverse, ridges added to the piston bowl - is fundamentally the same..

& with the same expressed intent, being advanced combustion efficiency..