Hi all,

I am a student in engineering and as part of senior design project I need to know some information for my project model. Pretty much what it comes down to is I need to know the difference in temperature of exhaust gas before and after the turbo. Let's assume we are talking about cruising speed of 60 in overdrive in standard conditions (approximately 70 F), what ever that rpm may respond to. I know, it changes based on turbo and from truck to truck, but I just need a decent estimation to see if the project idea is worthwhile. So if some of you run gages pre-turbo, please let me know what kind of temperatures you are seeing. Same for post turbo. Also, do you guys happen to know if you would see similar temperatures in spark ignition engines?

The help is really appreciated. Thank you!

 

Had pre and post pyro on my 89, though not at the same time. At typical cruising speeds, as you describe, the temps differed by about 300 degrees F, give or take. Hope this helps

 

Yup, that definitely helps, that's the difference I was expecting to see. Now, I just have to figure out how much of that goes to potential work and how much is due to heat transfer. Thank you for the reply!

 

You want to get a sample at higher boost, when the turbine will actually be doing more work. 5 psi isn't a high workload when it could be running 45+.

 

Yes, I understand that. The current goal is to see what is the potential to do work (ie find the exergy) at normal driving conditions. The next step would be performing similar analysis at various conditions. I will have to develop an algorithm that will take into account all these variables once I am certain that I can get what I need at cruising conditions. Thanks.

 

When I had two gauges the temp was usually 300°F different but at higher boost could go as much as 500° higher pre turbo.

 

How are you going to estimate the properties of the air moving through the engine bay to estimate loss due to convective heat transfer?