SC air temp vs TC air temp
10-18-2009, 08:34 AM
#1
0.0 BAR
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Join Date: Jan 2006
Posts: 43
SC air temp vs TC air temp
Watching 2 of my friends having small debate about this which kind of interesting.
Given SC compressor producing X amount of CFM @ 14psi VS turbo producing the same CFM as SC compressor @ 14psi, will the air temp of both same?
Given SC compressor producing X amount of CFM @ 14psi VS turbo producing the same CFM as SC compressor @ 14psi, will the air temp of both same?
10-22-2009, 03:52 PM
#4
1.5 BAR
Join Date: Jan 2006
Posts: 779
yeah there are more factors than just cfm and pressure ratios. what if you have a decent supercharger running 18psi then you take a small *** 13g and run it @ 18 psi the turbo will heat it up way more. so your argument is pointless with your friend unless you are talking specific s/c and specific turbo on a specific car. there are to many variables to just say one creates more heat than the other
10-23-2009, 02:01 AM
#5
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Well i think that is the reason why he emphasis on CFM alot. I think he is trying to say given 2 same "size" compressor (turbo/SC).
Lets put it this way. A turbo producing 500cfm @ 1bar vs centrifugal compressor generating 500cfm @ 1bar, will they having same air temp? Lets see this w/out IC
Lets put it this way. A turbo producing 500cfm @ 1bar vs centrifugal compressor generating 500cfm @ 1bar, will they having same air temp? Lets see this w/out IC
11-08-2009, 06:22 AM
#8
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If you mean a centrifugal supercharger, and assuming the supercharger and the compressor side of the turbocharger have the exact same specifications, and use the same map, then there should be no difference in heat in an otherwise identical setup.
Same compressor map, same airflow, same pressure ratio, same temperature.
However this would be impossible to acheive in a real life situation.
Same compressor map, same airflow, same pressure ratio, same temperature.
However this would be impossible to acheive in a real life situation.
11-08-2009, 07:19 PM
#9
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If you mean a centrifugal supercharger, and assuming the supercharger and the compressor side of the turbocharger have the exact same specifications, and use the same map, then there should be no difference in heat in an otherwise identical setup.
Same compressor map, same airflow, same pressure ratio, same temperature.
However this would be impossible to acheive in a real life situation.
Same compressor map, same airflow, same pressure ratio, same temperature.
However this would be impossible to acheive in a real life situation.
11-08-2009, 11:35 PM
#10
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Join Date: Nov 2009
Posts: 2
tl;dr version: Roots type superchargers blow lots of hot air.
Full version with evidence:
Roots type superchargers are only efficient at low supercharger RPMs. Just look how the map is shaped:
The horizontal axis is airflow, vertical axis is boost pressure, the percentages are efficiency. The less efficient, the hotter the air. As you can see, at 15psi its only 55% efficient. So the air would be quite hot.
Here's a turbo map:
Notice that the lowest percentage is 65%, and for a given airflow around 8-18psi boost its 72% efficient!
Turbos and centrifugal superchargers are much more efficient than a roots type blower. Screw type blowers are somewhere inbetween.
Full version with evidence:
Roots type superchargers are only efficient at low supercharger RPMs. Just look how the map is shaped:
The horizontal axis is airflow, vertical axis is boost pressure, the percentages are efficiency. The less efficient, the hotter the air. As you can see, at 15psi its only 55% efficient. So the air would be quite hot.
Here's a turbo map:
Notice that the lowest percentage is 65%, and for a given airflow around 8-18psi boost its 72% efficient!
Turbos and centrifugal superchargers are much more efficient than a roots type blower. Screw type blowers are somewhere inbetween.
