Throttle wins system

[mort]

Originally Posted by jakobnev

It seems you and i disagree on whether air is compressible or not.

(Clue: Your formula is accurate for hydro power)

Hi jakobnev,
I guess that's sarcasm.
In the case of the automotive engine, we don't need to know about the compressability or heat capacity or any other characterisics of the fluid. Neither does the actual shape of the restriction matter. We don't need to CALCULATE the force required to move the air through the throttle. We simply measure that force. Power is equal to the force times rate of flow.

-mort

[drmiller100]

To summarize, the members are arguing pumping losses are insignificant for a gasoline engine, and turbo chargers work off of only the mass of the exhaust gasses passing through them (and heat doesn't matter), and variable vane turbos are too far in the future to be worth worrying about.

[mort]

Originally Posted by drmiller100

To summarize, the members are arguing pumping losses are insignificant for a gasoline engine, and turbo chargers work off of only the mass of the exhaust gasses passing through them (and heat doesn't matter), and variable vane turbos are too far in the future to be worth worrying about.

Hi drmiller,
as Homer says, "Your ideas are intriguing to me and I wish to subscribe to your newsletter."

Merry Christmas to all.
-mort

[dcb]

Are you designing a new crack pipe?

[pete c]

not just any crack pipe, a super efficient crack pipe.

[mwebb]

1.pumping losses are not Insignificant in gasoline engines
2. variable vane turbos have been in production and use in VWs for many years
3.gasoline engines with direct injection still use throttle plates or variable lift intake valve to control air flow to the intake and by so doing
MUST have suction throttling loss es / pumping losses

AFR in gasoline engines is controlled to be near 14.7 to 1 much but not all of the time in direct injection gasoline engine systems and it could NOT be controlled if air flow were to be UN controlled as it is in a older diesel engine / remembering that air flow is regulated / controlled in newer diesel systems by a
throttle plate , primarily used to
increase EGR flow by increasing pressure delta betwixt exhaust and intake ,
also
throttle plate is used to stop the diesel engine right now when key is switched to off in current production diesel engines with direct injection, assuming there is a "key" .

the throttle plate in newer diesel engines does increase pumping losses / suction throttling loss and the throttle plate in the exhaust (also used to increase EGR flow ) does not help in that regard either

to winterize

Originally Posted by drmiller100

To summarize, the members are arguing pumping losses are insignificant for a gasoline engine, and turbo chargers work off of only the mass of the exhaust gasses passing through them (and heat doesn't matter), and variable vane turbos are too far in the future to be worth worrying about.

[mwebb]

could you / is it possible
to spin a shaft using suction throttling loss at cruise ?


YES
any energy so acquired would be "free" as the loss has already been incurred assuming the value of the energy exceeds the amount lost to "friction" of one form or another in the contraption used to get the energy

[Frank Lee]

I think depending on configuration of the turbine it might need a throttle plate besides in order to achieve a low idle?

[mwebb]

yes it would and
hardware and software to control when the two switch back and forth

as well
it is a bad idea to take heat from the exhaust as that will screw up exhaust flow , especially when there is plenty of extra heat and some pressure available from ducting the back side of the radiator ala
Meredith effect ...

gains would be small , but gains are gains

Originally Posted by Frank Lee

I think depending on configuration of the turbine it might need a throttle plate besides in order to achieve a low idle?

[dcb]

Originally Posted by mwebb

[COLOR="Blue"]...
3.gasoline engines with direct injection still use throttle plates or variable lift intake valve to control air flow to the intake and by so doing
MUST have suction throttling loss es / pumping losses

I don't think the ecoboost has a throttle, I don't know why it would need one either. The original (i.e. 50 years ago) direct injection schemes had a throttle, but I don't think it is a requirement these days. What am I missing here?