Camaro XV

[65 347]

Mark
The car looks outstanding! Cant wait to see it this week. The paint is stunning.

Mike

[frojoe]

Originally Posted by Stielow

I had Dewitt’s radiator custom make me a radiator core and intercooler core. The cores nest together to make an efficient package. The assembled the cores with tanks and mounted them togther. I had it made 23 inch tall and 24 inched wide to fit a Cadillac SRX turbo fan and shroud. After a long conversation with C&R they supplied a 10 kW oil cooler for the end tank. Dewitt also built in the power steering and transmission coolers. It maybe a bit overkill but I want to get the temps under control on the new car.



The top two coolers are power steering and transmission. The lower cooler is the engine oil cooler. Using oil to water coolers it will help heat and cool the oil.



Mark

Mark, what is the fan shroud (ei fan blade leading edge) gap from the radiator core? You quote 850W heat rejection for the fan, but is there an equivalent vacuum or airflow (cfm) value that you can attach to that heat rejection rate? Also lastly, what is the core thickness of the radiator?

Thanks!
Joe

[mikels]

Originally Posted by frojoe

Mark, what is the fan shroud (ei fan blade leading edge) gap from the radiator core? You quote 850W heat rejection for the fan, but is there an equivalent vacuum or airflow (cfm) value that you can attach to that heat rejection rate? Also lastly, what is the core thickness of the radiator?

Thanks!
Joe

OEM fans are not typically rated in CFM. 850W is simply (volts x amps).

Obviously, that is not enough to design to for cooling requirements, so a volume flow rate vs. pressure drop is required - this is where many fans fall short as they are rated in CFM @ 0 (zero) pressure drop - which is not how you are using them (And some have dramatic loss in flow with pressure drop).

The SRX turbo fan flows:
~1.0 m^3/sec @ 300 Pa pressure drop (2119 CFM @ 1.2"H2O)
~1.5 m^3/sec @ 225 Pa pressure drop (3178 CFM @ 0.9"H2O)

So pressure decrease of 25% results in flow increase of 50%. Now you can see why flow curve (mass flow vs. pressure drop) is what you are really looking for in fan specifications.

If you extrapolate flow curve for SRX turbo fan, flow @ 0 pressure drop is on the order of ~2.5 M^3/sec (5300 CFM). (not 100% accurate as flow rates become non-linear at very high and low pressure drops)

You really need to know what the pressure drop is through your cores to determine flow rate of fans (that combined with heat exchanger efficiency will give you kW heat rejection).

BTW- Modern high-efficiency cores are WAY more efficient than old-school designs - so not as simple as looking at core thickness, size, etc..

Dave

[clill]

Jesus fricken Christ Mikels.....speak English....

[mikels]

Originally Posted by clill

Jesus fricken Christ Mikels.....speak English....

OK Charlie:

Big fan move sh**load air!

Dave

[Sieg]

Originally Posted by clill

Jesus fricken Christ Mikels.....speak English....

Originally Posted by mikels

OK Charlie:

Big fan move sh**load air!

Dave

Thanks for a good laugh Gents!

[Che70velle]

Have to admit, that's comedy!
Dave, thanks for this info. I'm gonna file this, as I've never found this info anywhere, and I'd say with your credentials, your a trustworthy source of info.

[SlowProgress]

Funny !!

[waynieZ]

Originally Posted by clill

Jesus fricken Christ Mikels.....speak English....

Charlie I think you read my mind!

[frojoe]

Originally Posted by mikels

OEM fans are not typically rated in CFM. 850W is simply (volts x amps).

Obviously, that is not enough to design to for cooling requirements, so a volume flow rate vs. pressure drop is required - this is where many fans fall short as they are rated in CFM @ 0 (zero) pressure drop - which is not how you are using them (And some have dramatic loss in flow with pressure drop).

The SRX turbo fan flows:
~1.0 m^3/sec @ 300 Pa pressure drop (2119 CFM @ 1.2"H2O)
~1.5 m^3/sec @ 225 Pa pressure drop (3178 CFM @ 0.9"H2O)

So pressure decrease of 25% results in flow increase of 50%. Now you can see why flow curve (mass flow vs. pressure drop) is what you are really looking for in fan specifications.

If you extrapolate flow curve for SRX turbo fan, flow @ 0 pressure drop is on the order of ~2.5 M^3/sec (5300 CFM). (not 100% accurate as flow rates become non-linear at very high and low pressure drops)

You really need to know what the pressure drop is through your cores to determine flow rate of fans (that combined with heat exchanger efficiency will give you kW heat rejection).

BTW- Modern high-efficiency cores are WAY more efficient than old-school designs - so not as simple as looking at core thickness, size, etc..

Dave

Thanks Dave, this data is literally exactly what I was hoping for, but being the internet, was not expecting it!

I was also asking for core thickness as a reference for the rough resistance that the fan would be working against statically (not including added resistance of IC in front). Obviously dynamically there are added factors under speed such as ram air effect on some of the frontal area as well as pressure differential across the "cooling stack" due to chin spoiler, etc... just looking for a rough idea of if it's a 2", 3.5", or 17.623578" thick core.

Cheers,
Joe