demand on turbocharged air flows

[MBT]

on some modern diesel engines there is the suction butterfly valve, on the filter airbox
I don't know though if it is used for "egr"istic purposes or just to turn off the mud gently

 

[Goticaa85M]

There had been some studies on the 1.9 mjet 16v (year 2002/2003) to check what the butterfly valve insertion involved, especially in the widening range of egr intervention: in practice we wanted to choke the aspiration also of diesel so as to increase the deltap exhaust collector/suction manifold and thus increase the scope of egr even to the higher loads.
I had carried out theoretical simulations at the control level together with other colleagues for the crf, perhaps they had also made some evidence at the counter, I lost a little the wrist of the thing and I don't know if it was ever adopted as a standard solution. the risk if I do not remember badly was to go to "rovinare" combustion with too many inerts, as well as other repercussions on the dynamics of the turbo precisely.
I came out quite "pretty" from the motor field:frown:

bmw engines have been inserted, they are an example... they are developing on engines with fap to adjust the temperatures on the catalyst and bring it first in temperature to start. the egr, in addition to ruining the combustion, greatly harnesses the intake collectors and valves, with everything that follows...I should have some photos of the collectors with egr... :smile:

 

[MBT]

to say that there is no stenchiometric relationship is a force... it exists.
the diesel engine is made to operate in excess of air, in particular fixes a minimum value of excess under which you try not to go down to avoid bad combustion and problems on the engine (the most obvious is smoking, but there are others...). As far as the maximum of excess is regulating, there is no limit (well, if you push too far the combustion does not happen) but depends strongly on the emissions of pollutants. to give you an idea consider these two points:
1. so much air = production of a few hc and co, but very nox;
2. little air = contained production of nox but many hc and co.

Yes, it's a force. I know.
but it is to explain to large lines the substantial difference between disel and gasoline
while in gasoline if you exit the stenchiometric ratio the motor does not turn, in diesel the only limit is higher
both statements written above are incorrect, but make the idea good

 

[Goticaa85M]

Yes, it's a force. I know.
but it is to explain to large lines the substantial difference between disel and gasoline
while in gasoline if you exit the stenchiometric ratio the motor does not turn, in diesel the only limit is higher
both statements written above are incorrect, but make the idea good

I know they're not exactly correct. In fact, I wrote "to get an idea..."

However the butterfly is inserted mainly for reasons of egr...close the aspiration to favor the entry of exhausted gases in aspiration.

ps. paulpaul I attach you a photo of an aspiration conduit with egr after 100k km... was an alpha 1.9 jtdm 150 mounted on a...

 

[snaroz]

Perfect, guys!
the concept is essentially this:
1) turbo petrol, constant speed, constant power. I press the accelerator to the maximum, opens the butterfly and all the air out of the compressor goes into the engine. the injectors adapt and increase the flow to the optimal ratio. The machine starts to accelerate. immediately after the engine does not "push" more: the exhaust gases that go into the turbine, due to the mass and inertia of the impeller, take some time to accelerate it, and consequently the compressor takes time before increasing its speed of rotation. the result of this is that you have to wait for seconds before the compressor can force even more the air in the cylinders;
2) td. ignite the accelerator, the injectors increase the flow to the maximum value reached with that amount of air in the cylinders. the power therefore increases almost instantly, but for a short time: in fact, the new exhaust gases will take some time to speed up the compressor, with the result that you cross a phase of a few seconds in which the engine does not seem to "push" properly. are there (at least intuitive)?

 

[MBT]

Perfect, guys!
the concept is essentially this:
1) turbo petrol, constant speed, constant power. I press the accelerator to the maximum, opens the butterfly and all the air out of the compressor goes into the engine. the injectors adapt and increase the flow to the optimal ratio. The machine starts to accelerate. immediately after the engine does not "push" more: the exhaust gases that go into the turbine, due to the mass and inertia of the impeller, take some time to accelerate it, and consequently the compressor takes time before increasing its speed of rotation. the result of this is that you have to wait for seconds before the compressor can force even more the air in the cylinders;
2) td. ignite the accelerator, the injectors increase the flow to the maximum value reached with that amount of air in the cylinders. the power therefore increases almost instantly, but for a short time: in fact, the new exhaust gases will take some time to speed up the compressor, with the result that you cross a phase of a few seconds in which the engine does not seem to "push" properly. are there (at least intuitive)?

kit in red
1) turbo petrol, constant speed, constant power. I press the accelerator to the maximum, opens the butterfly and all the air out of the compressor goes into the engine. the injectors adapt and increase the flow to the optimal ratio. The machine starts to accelerate. increases the amount of exhaust gas that are expelled from the engine and that go in turbine due to the mass and inertia of the impeller the compressor takes time before increasing its rotation speed. the result of this is that you have to wait for seconds before the compressor to the new balance regime;

2) td. ignite the accelerator, the injectors increase the flow to the maximum value reached with that amount of air in the cylinders. increases the amount of exhaust gas that are expelled from the engine and that go in turbine due to the mass and inertia of the impeller the compressor takes time before increasing its rotation speed.In fact, the new exhaust gases will take time to speed up the compressor, with the result that you cross a phase of a few seconds in which the engine does not receive enough air and power increases but associated with exhaust smoke.

If you've ever driven a turbo car, you'll notice that you wrote inaccuracies.
there is never a "botta" followed by a vacuum
If you accelerate from the low regimes, you will feel a "empty" (relative, the engine still starts pushing. ..) followed by a bang when the turbine accelerated and arrived at regime

 

[Goticaa85M]

kit in red
1) turbo petrol, constant speed, constant power. I press the accelerator to the maximum, opens the butterfly and all the air out of the compressor goes into the engine. the injectors adapt and increase the flow to the optimal ratio. The machine starts to accelerate. increases the amount of exhaust gas that are expelled from the engine and that go in turbine due to the mass and inertia of the impeller the compressor takes time before increasing its rotation speed. the result of this is that you have to wait for seconds before the compressor to the new balance regime;

2) td. ignite the accelerator, the injectors increase the flow to the maximum value reached with that amount of air in the cylinders. increases the amount of exhaust gas that are expelled from the engine and that go in turbine due to the mass and inertia of the impeller the compressor takes time before increasing its rotation speed.In fact, the new exhaust gases will take time to speed up the compressor, with the result that you cross a phase of a few seconds in which the engine does not receive enough air and power increases but associated with exhaust smoke.

If you've ever driven a turbo car, you'll notice that you wrote inaccuracies.
there is never a "botta" followed by a vacuum
If you accelerate from the low regimes, you will feel a "empty" (relative, the engine still starts pushing. ..) followed by a bang when the turbine accelerated and arrived at regime

I was answering, but mtb anticipated me! :biggrin:

 

[snaroz]

thanks:finger:
I had an idea, but, of course, I've been studying.

 

[Enigma]

If you accelerate from the low regimes, you will feel a "empty" (relative, the engine still starts pushing. ..) followed by a bang when the turbine accelerated and arrived at regime

maybe now I go ot.....to avoid these "empty" and "bows" that are typical of the motors turbo so many motors (aspirated) adopt a system of "variable phase of valves"
This system optimizes the power supply (refacing the camshaft) and makes the engine under a certain speed of turns more "soft" (by reducing consumption) while at high turns the engine "urla" (consuming like a v2 missile experience that I live every day with my celica toyota:finger. .

enigma
http://www.youtube.com/watch?feature=endscreen&v=h-zhbnj3zti&nr=1

 

[Goticaa85M]

maybe now I go ot.....to avoid these "empty" and "bows" that are typical of the motors turbo so many motors (aspirated) adopt a system of "variable phase of valves"
This system optimizes the power supply (refacing the camshaft) and makes the engine under a certain speed of turns more "soft" (by reducing consumption) while at high turns the engine "urla" (consuming like a v2 missile experience that I live every day with my celica toyota:finger. .

enigma
http://www.youtube.com/watch?feature=endscreen&v=h-zhbnj3zti&nr=1

mic only aspired....there are also turbos that vary the pressure of the valves, especially the suction ones: do you know the miller cycle for td engines?

 

[Enigma]

mic only aspired....there are also turbos that vary the pressure of the valves, especially the suction ones: do you know the miller cycle for td engines?

I don't know him, in my deep ignorance I thought that the "variable phase" was applied only to "aspired" engines. . .

enigma

 

[Goticaa85M]

I don't know him, in my deep ignorance I thought that the "variable phase" was applied only to "aspired" engines. . .

enigma

is also used in turbos...one of the greatest benefits lies in the variation of overlapping time: it increases to high loads so you get a better washing and a May cooling of the room, while it is reduced to low to avoid negative washing.

 

[paulpaul]

I know they're not exactly correct. In fact, I wrote "to get an idea..."

However the butterfly is inserted mainly for reasons of egr...close the aspiration to favor the entry of exhausted gases in aspiration.

ps. paulpaul I attach you a photo of an aspiration conduit with egr after 100k km... was an alpha 1.9 jtdm 150 mounted on a...

:smile:
In his time they told me that on the first versions of the 16v mjet the butterfly was mounted but blocked open... waiting for further investigations on his behavior. I don't know how much this corresponds to the real and I don't know which series they started to run it instead! I'm talking about the end of 2003, then as I said, I lost a little bit of the tour.

However, I see that the subject is always very successful, especially when it is intertwined with the subject overpowered! !

 

[snaroz]

Hello guys: who of you here graduated in mechanical engineering? with what specialization?
Thank you!

 

[Goticaa85M]

:smile:
In his time they told me that on the first versions of the 16v mjet the butterfly was mounted but blocked open... waiting for further investigations on his behavior. I don't know how much this corresponds to the real and I don't know which series they started to run it instead! I'm talking about the end of 2003, then as I said, I lost a little bit of the tour.

However, I see that the subject is always very successful, especially when it is intertwined with the subject overpowered! !

Well, for now, I'd say that my feet are the present and the next future, so it's normal that it's a constantly evolving field!

even if they have intrinsically a limit that they will never exceed..

 

[paulpaul]

Well, for now, I'd say that my feet are the present and the next future, so it's normal that it's a constantly evolving field!

even if they have intrinsically a limit that they will never exceed..

for example you will never have any returns from electric motors from a mci!!!

 

[Paolo Molniya]

for the problem of low power to low regimes, you have only talked about the solution of the turbo with variable geometry, but as a fan of lance I would like to quote the volumetric coupling with turbocharger present on the legendary abarth s4 lance.
http://youtu.be/e-lu4oqsf-a?t=50severy time I get my tears down:biggrin:

 

[MBT]

maybe now I go ot.....to avoid these "empty" and "bows" that are typical of the motors turbo so many motors (aspirated) adopt a system of "variable phase of valves"
This system optimizes the power supply (refacing the camshaft) and makes the engine under a certain speed of turns more "soft" (by reducing consumption) while at high turns the engine "urla" (consuming like a v2 missile experience that I live every day with my celica toyota:finger. .

enigma

is also used in turbos...one of the greatest benefits lies in the variation of overlapping time: it increases to high loads so you get a better washing and a May cooling of the room, while it is reduced to low to avoid negative washing.

exact
the variable timing is, however, a "pagliativo" (cit.... :biggrin that reduces the problem
much more performing is the v-tec system, but it is patent and home honda.

If one day they gave birth to a v-tec turbo there will be really fun.
mortgage rata stuff for a "sporty" ride, but extremely fun!

for the problem of low power to low regimes, you have only talked about the solution of the turbo with variable geometry, but as a fan of lance I would like to quote the volumetric coupling with turbocharger present on the legendary abarth s4 lance.
http://youtu.be/e-lu4oqsf-a?t=50severy time I get my tears down:biggrin:

It's a beautiful beast. .

About superpower
Do you know this?

 

[Paolo Molniya]

It's a beautiful beast. .

About superpower
Do you know this?

the patent tablet of the "brown boveri"

 

[Paolo Molniya]

If one day they gave birth to a v-tec turbo there will be really fun.
mortgage rata stuff for a "sporty" ride, but extremely fun!

the subaru if not mistaken won the prize "motor of the year" (or something similar) in 2006 when he presented the new ej22 2500cc four opposing cylinders, turbo, almost 40 kilogrammeters of pair and 280 horses, with avcs system (active valve control sistem) that is a variable fasatura on the only suction valves. . road:biggrin:


p.s.: who remembers this attached? You still see some golf around...