Being an x-miata owner and now "S" owner, I currently am trying to obsorb and learn all I can about turbo's and supercharger's as I hope to go FI one day. I still get on M.Net and currently there has been a debate going on that blossomed from a question to a full scale debate riot.
To me, you guys seem to be the most knowledgable about both of these systems, and I thought that you would enjoy taking a break and reading this. Parts of it are pretty funny.

http://forum.miata.net/vb/showthread.php?t...96&page=1&pp=25

 

turbos tend to cause more engine damage. I should join there just to flame

 

I read three posts, and then couldn't stand the ignorance any longer.

 

lol they both have their ups and downs but i didnt know that the miata guys were so biased lol....

 

Since you are a former miata guy you know who BRP was and now that they are called Stage One Tunning (SOT). There are a couple s2k owners runnign there MP62 based supercharger for the S2000.

Me included as the first AP2 Beta tester


some home work for you


Some light reading about the MP62 roots
https://www.s2ki.com/forums/index.ph...f=142&t=625078

Some heaving reading about the MP62 Roots
https://www.s2ki.com/forums/index.ph...f=142&t=467853





you should not have many questions after reading all of these threads



https://www.s2ki.com/forums/index.ph...f=142&t=647816
https://www.s2ki.com/forums/index.ph...f=142&t=620328
https://www.s2ki.com/forums/index.ph...f=142&t=645463
https://www.s2ki.com/forums/index.ph...f=142&t=629708
https://www.s2ki.com/forums/index.ph...f=142&t=625086
https://www.s2ki.com/forums/index.ph...f=142&t=611081
https://www.s2ki.com/forums/index.ph...f=142&t=610640
https://www.s2ki.com/forums/index.ph...f=142&t=586141
https://www.s2ki.com/forums/index.ph...f=142&t=560371

 

I can not believe that

screen name "Corky Bell" even if it is truly him and "Stephanie Turner" who is also supposedly known over on Miata net as knowledgeable both said


absolute wrong....


turbos run on pressure differential and mass flow accost the turbine. The temperature difference between the inlet and outlet on the turbine is not a function of work done to turn the driving shaft it is a function of surface area and radiated heat out of the housing.

If and only if the housing was insulated so it would not transfer/extract heat out of the exhaust gas then and only then could you accurately calculate how much of this so called heat work (AKA energy) was lost (AKA used according to them) to turn the turbine..

the temp difference between the inlet and outlet on a turbine is part of the equation to determine how much work ( or more accurately the efficiency of the work ) has been applied to the turbine wheel. Not what was the mechanism by which the work was applied.

AS an example in a stem turbine the temperature in and out is taken into account because of a phase change in the medium that is applying the work to the turbine.

That same process/theory can not be applied to a turbo because the exhaust gases are not going through a phase change. The difference in temp ( even thought minimal) is because of conduction through the turbine housing not the so called work done by the heat.


I have never seen a turbo spin by placing it in an oven........

the mass flow, exhaust velocity, and the pressure differential along with the turbine design parameters trim, AR ect. determine how well a turbo operates not the heat it is subjected to.


Sorry guys but the statement "Turbos run on heat: all ways bothers me.

 

Thanks for the laugh, LOL.. so true

 

i lol'ed a lil bit on that one myself lol....

 

Don't want to get in an Internet fanboi argument, but it is certainly true, if overly simplified.

The turbine in a turbocharger certainly is a heat engine and uses the heat from the exhaust gas to do work.

And that guy over at the Miata forum truly is Corky Bell, and he has written a few books on the subject of FI.

 

neither do I.
And I have read KBs books

If you want to get very very technical then you can say that the temp difference that is not lost to conduction is enery supplied to the turbine and is work acting upon the turbine. It must be used/go some where ( law of conversation of energy)

However that energy (heat ) used to do work is so small in comparison to the work performed by the pressure diff and mass flow that this heat energy part of the equation is usually dropped from the work calculation for turbines specifically the design in the turbines of turbos for internal combustion engines.

You can not just apply the calculations for work applied to a turbine where there is a phase state change in the working fluid ( aka steam turbines) to turbine calculations for turbos uses on internal combustion engines.

A turbo is not a heat (energy) recovery system it is a mechanical system.

even wikipedia has that aspect wrong.

Again
If it was infact a heat engine and the housing was insulate to prevent temperature from escaping through the housing, once everything has reached steady state conditions the temperature of the working fluid coming in is going to be very close to the temperature of the working fluid coming out. Which again means that the none of this heat ( energy) was recovered ( aka used to perform work) on the turbine and spin the shaft.


End the end if

Car A is putting down 300/200 at 5.5 psi with a supercharger

And

Car B is putting down 300/200 at 5.5 psi with a turbo.

With the same exact area under both the TQ and HP curve

then

Both Car A and Car B are equally efficient at producing power at the same CFM/boost level.


In the end believe what you want.....turbos run on heat or they don