Diesel turbo questions.

[KiwiBacon]

Originally Posted by UncleBob

how the turbo works is off of pressure differential. There must be more flow over the turbine than the compressor is producing....otherwise you have what we like to call "perpetual motion"

Although PSI does not equal flow directly, its definitely related.

The energy driving a turbine isn't just the pressure, it's also the temperature. The greater temperature differential you can get (i.e. very hot exhaust into turbine, cooler exhaust out) the less pressure differential you need.

It's not a perpetual motion machine until the compressor is doing more work than the turbine is creating.

I've got a spare thermocouple lying around, but I haven't yet measured the temp drop across the turbine.

[UncleBob]

Originally Posted by KiwiBacon

It's not a perpetual motion machine until the compressor is doing more work than the turbine is creating.

uh....thats exactly what I said.

[KiwiBacon]

Originally Posted by UncleBob

uh....thats exactly what I said.

You neglected the temperature part. It's entirely possible to have more boost than backpressure if the temps are high enough.

Work is pressure and temperature. Not pressure alone.

[UncleBob]

Originally Posted by KiwiBacon

You neglected the temperature part. It's entirely possible to have more boost than backpressure if the temps are high enough.

Work is pressure and temperature. Not pressure alone.

flow is flow. As I said, pressure is one portion of the equation