Originally Posted by clm2112
Originally Posted by willwren
TB icing is the concern on cold starts for all vehicles, but it'* also ideally located for SC cooling. I have thermal analysis on the M62 as well as temperature sensors all over mine. The hottest portion of the SC in operation is the inside face of the inlet directly behind the TB.
Good thinking on GM'* part if you ask me.
That makes no sense at all. Where'* the heat coming from? It can't be from the SC, since the heat from that is at the middle and output side where the air is actually being compressed. Is the heat comming from the EGR gasses perhaps?
Some of the heat bleeds over from the nosedrive end from friction. Makes sense.
Some of the heat is produced by compressing air in the rotor housing. Makes sense.
Some of the heat is produced by the needle bearings on the end of the rotors by the TB.
Some of the heat is produced by the EGR valve, but not much.
The bulk of the heat produced under boost is from the inlet of the SC as all that air has to squeeze down to enter the inlet of the SC. This is compounded by the rough-cast surface the Eaton Superchargers have from the factory.
Under normal driving conditions, the SC may not heat up to the point that the coolant would be beneficial, but under high-boost runs at a dragstrip, my research shows the coolant to be beneficial in aiding the cool-down of the SC, as the temps spike very high after a run at WOT. A cooler thermostat with a larger opening helps some with this. The cooldown occurs much more quickly with the right selection of thermostats.
The cooler surfaces are a darker color. The hotter surfaces are lighter. Note the inlet.
This is why I started working on this:
It bypasses the coolant at the LIM and provides a seperate cooler source to continue the flow and remove heat from the inlet area of the SC and TB.
I have not built it, but have done some thermal dynamics testing on the model, and plan to do more. The expense is far more significant in the other work involved to make it fit, rather than the machining.
In this pic, you can see one of my temperature strips. There are a total of 8 of them on the SC and TB so I can track the temp flux through the top end.