you people think too much. Just bolt a turbo on your car and see what happens, who cares about the theory behind it.
Say we extend this to the limit. What if we cooled the cold balloon to the point were the gas inside it is the same pressure as the atmosphere. You hook up the little turbine and you measure zero energy.
So hot balloon produces X Joules of energy, cold balloon produces zero Joules of energy. A third baloon with same mass of air etc. somewhere between the hot and cold balloon temperatures would be Y joules of energy.
So from this, I think it is safe to say that X is greater than Y is greater than 0.
Stirling
you people think too much. Just bolt a turbo on your car and see what happens, who cares about the theory behind it.
I just wanna make mention that the baloon example is flawed. You are measuring the energy stored in the baloon. A baloon full of hot air is stretched further, and has more energy stored. Exhaust pipe is not elastic.
An engine pumps the same amount of exhaust gas (mass) out constantly. Without resistance, the mass throughput at any time is the same. With resistance, it will level out to be the same throughput, but dynamic characteristics may result in a delay while the smaller volume cold air can build pressure. Hot air will occupy more volume and build pressure faster. Flow over a resistance is based largely on pressure differential, and a number of less significant factoes like density etc...
Remote turbos to me sounds like potentially tragic lag. I usppose a 7L v8 isnt poor to start tho. If the throttle bodies are close or direct to head, it would reduce the plenum volume in vacuum, but there is still a lot of volume in lines to fill.
Cheers!
What I thinks y'all fighten about is different applications of the same basic rules - i.e. transfer of energy by mass. E.g. one ton of water following over a waterfall can be made to do the same amount of work whether falling in 1 minute, one hour or one year - it will just take the minute, hour or year to do the work. BUT the water will do more work if the height of the waterfall is greater. I.e. the pressure (or in my example, height of the waterfall) makes a difference, not just the mas involved. Otherwise cars hitting each other at 10kph would do exactly the same amount of damage as cars at 100kph - they have the same mass after all.
The other cause for confusion here is that the exhaust gas is not pushing out the exhaust pipe against nothing (vacuum) but against air pressure, so reduction in pressure before the turbo DOES impact the efficiency of the turbo, equivalent to decreasing the height of the waterfall. Of course, the arguements for resistance etc apply whether the turbo has an additional pressure gradient before or after it, but the flow rate has a large impact on the resistance of the pipe. For the "mass mover" theorists, remember that there's a fairly large mass of air outside the motor which would press in if given the chance, e.g. the air "drawn in" by the turbo is actually pushed in by air pressure.
Steve
2003 Discovery 2a
In better care:
1992 Defender
1963 Series IIa Ambulance
1977 Series III Ex-Army
1988 County V8
1981 V8 Series 3 "Stage 1"
REMLR No. 215
I'll admit this has dragged on a bit, but it's interesting stuff... well, for me anyway. And it's always fun to have a good juicy debate.
Stirling
I was waiting for you to have a dig rovercare.I think the part about 7ltr V8 might mask alot of the problems such as lag etc.I would be nice to have the money to try out a couple of theorys though. Pat
why is there a thums down on my post? i didnt put it there
All of the above. Main problem is owners with high expectations, long pockets, and poor recall of advice and recommendations. Pressure charging engines not designed to be so, is a complex frustrating business. Spend enough time and money and progress can be made but not always to the expectations or needs of the owner. The gear was usually brought to me to fit or fix something bought or started by someone else. Most common are the owners who think bunging a blower or hairdryer on their 10yo supermarket trolley will make it into a supercar. Does not happen!!! For a street car, a blower that puffs max. 8psi over atmospheric will give good low speed torque without too many problems. If you want to get and use 16psi boost then expect big bills and problems. I am speaking of petrol engines.
URSUSMAJOR
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