Cooling system test lab

[TChronos]

I wonder if anyone could point me to a test lab in the US that can do heat rejection testing on automotive radiators. I'm trying to decide between three sample designs, and could use some actual measurements.

 

[MintJulep]

Could likely be accomplished by any half-way decent lab, or even in a simple home-made test contraption.

One name would be

http://www.intertek.com/

 

[patprimmer]

Hmm

Not at all my area, but I would think controlled flow of coolant and air as well as temperature in, temperature out measurements for coolant and air would yeild a lot of data. The ability to also measure and control flow rates of each would be all that was required I would think.

Coolant flow rate is easy. Measure time to fill a container of known volume.

Air flow is harder. I guess an aircraft air speed indicator along with pressure readings would do. Heck, it could be roughly calibrated by strapping it to the roof of a car and taking it for a drive on a calm day with a few runs each way and repeat until you get a stable average. Use sat nav or known accurate mileposts to calibrate car speed.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[1gibson]

Ff determining relative performance is the only objective, use the same fan and shroud for each radiator, use the same flowrate, measure temp in, temp out, and ambient temp (keep constant if possible.)

 

[IceStationZebra]

The testing isn't too complicated, but how you set up the test will be.

If you use the same fan set-up, as 1gibson suggests, you will most likely have different air flow rates between the three. Then you are comparing apples to oranges. I would think it would be more informative to take 3 or 4 flow points and get the flow/pressure vs. heat rejection curves. If you have the rig set up it would only take more time.

Same goes for coolant flow. Different designs will have different gpm vs. water pressure. If you have a specific engine in mind you could use its water pump driven by an electric motor.

You will need to regulate the water temperature going into the radiator to a constant temp.

ISZ

 

[1gibson]

The same fan/shroud setup generating different airflow through the different radiators is very likely. It is also a real world factor that needs to be considered when looking for "the best" radiator. Same for coolant flow. All other things constant, a radiator that can flow more air and water should have an advantage that will be reflected in the temperature drop. I am assuming he will also be looking for "the best" fan and water pump, which is beyond the scope of this question. Also assuming they are the same or very similar physical dimensions.

Comparing apples to oranges is fine in a number of scenarios. If you want to fit the maximum weight of fruit in an existing crate, you aren't going to check apples in one size crate and oranges in another. You're going to fill the crate with apples, put the lid on, weight it, then do the exact same with oranges. You're not going to change the dimensions of the crate from one fruit to the other.

Check idle conditions (fan only for airflow, water supply characteristics to emulate waterpump curve at idle engine rpm) and see which is best. You may be able to simplify things even further if you can maintain constant ambient temps. I assume the main objective is to avoid overheating at idle? Run a closed loop water system and log the temp rise until stable, and what the max temp is.

If this is for a research paper on radiator design, instead of a real world application, ignore these comments.