Hi has anyone measured the temperature of the charge air directly after the turbo? (i.e. after the air has been compressed by the turbo, but before the intercooler - where the charge air would be it's hottest)

I am specifying some materials which need to be able to handle the temperatures generated by the compression of the charge air and need to know what ball park temperatures I should be accommodating for.

Thanks

 

PV=nRT. That should get you in the ballpark. Add 10-20% as a safety factor for the heat picked up from a hot center section.

 

Thanks for the reply,

can you please define your variables? It's been a while since I've done any thermodynamics

 

(P2/P1) = (T2/T1)^(k/(k-1))

Where the pressures and temperatures are in absolute values, and k = ratio of specific heats = 1.4 for air. After you solve for T2, divide (T2-T1) by the efficiency of compressor, so about 0.70. Then add that value to T1. That should get you close.

So for 1.4 bar of boost, (we'll say 1 bar = 1 atm for simplicity), P2 = 2.4 bar, P1 = 1bar, T1 = 295K (~71F).

T2 = ~379K. T2 - T1 = 84. 84/0.70 = 120. So the final temp is about 120+295 = 415K or 288F.

 

I have measured around 5 different turbos. The bigger the turbo the cooler the air will be. The higher the boost the hotter the temp will be. What size turbo and boost level are you running?

 

fairly small turbo for now only running standard boost (10psi)
td04-13g on a 1800cc motor.

 

around 225 degrees.

 

thanks for the replies.

I'm planning on using some hose for the charge piping and it's rated to 212 degrees farenheit.

i know the charge air will exceed this temperature during full boost etc, but this is not (yet) a dedicated race car... so the amount of time spent on boost will most likely be intermittant.

 

I was being a bit of a smarta$$ in my first response. I apologize for that. Follow this link, it will help explain/calculate what you're looking for. About 3/4's of the way down the page.

http://www.enginelogics.com/cmaps.html

 

A large portion of you boost junkies drive them right off the top and right side of the comp maps, spend very little time in any area of decent efficiency, regardless of turbo size. Not that it matters much with modern IC's. Think 430-450+K. 350+F.

 

<just misread equation>

 

Ah I see Isentropic Compression. However this is unfinished and you need to solve for T2 only. I feel like I need to give you a chance to finish what you started.

Using the values in post #4 where gamma is equal to 1.4 since that is ratio of the specific heats of air solve for T2.

 

<just misread equation>

 

Instead of debating theoretical calculations just stick a temp sensor post turbo, which I have done in the past. Somewhere on this forum that data exists for the GTX3576r.

 

you aren't correcting misinformation, you are just proving you suck at algebra. the equation you posted and the equation in post #4 are the same just solved for different variables.