Engineers
Elite HDF Member
Joined: Nov 2010
Posts: 3,846
Likes: 173
From: Simi Valley, CA
First I would suggest that your cooler is designed for 100% open area and the screens you have proposed will be taking away your coolers ability to cool the oil. I don't see where you have identified the wire Guage or dimeter but have specified opening sizes with 25% to 52% open area. Imagine if you will that your oil is a huge heat sink and the more restrictive you cooler screen is the less the cooler is able to cool the oil. Also the oil will continue to have heat added by the motor and eponentially the heat stored in the oil will overtake the coolers abilities... but I would really think about the disadvantages of restricting your coolers air flow.
Stellar HDF Member
Joined: Aug 2012
Posts: 2,664
Likes: 184
From: Indiana, USA
Did you read post 18 by chance? Your post seems perfectly logical and is exactly what I would expect, but the testing I did says otherwise. My testing led me to the conclusion that the oil cooler's mechanical design is a much bigger contributor to the cooler's efficiency than moderate increases or decreases in airflow.
Elite HDF Member
Joined: Nov 2010
Posts: 3,846
Likes: 173
From: Simi Valley, CA
In my testing I measured oil temperatures with airflows between 31.2 and 52.5 CFM, a 68% increase from low to high, and saw no measurable oil temperature change under otherwise exactly identical test conditions.
Like I said, before conducting my testing I thought exactly as you. I fully expected the increase in airflow to have an effect on cooler efficiency, but it did not. And the results I'm reporting are not simply observations I made while riding my bike down the road (where there are many uncontrollable variations present). They are the results of highly controlled, laboratory quality test processes.
Last edited by 2black1s; Mar 28, 2013 at 01:27 PM.
Road Master
Joined: Oct 2009
Posts: 785
Likes: 2
From: SE TN
2black1s, just curious, did you notice any temperature difference in the cooler fins? Mathematically, did you expect any measurable change?
Elite HDF Member
Joined: Nov 2010
Posts: 3,846
Likes: 173
From: Simi Valley, CA
Measuring cooler fin temperature was outside the scope of my testing.
As for mathematical expectations, I didn't really have any. The testing wasn't done to validate any preliminary mathematical modeling.
Road Warrior
Joined: Nov 2008
Posts: 1,296
Likes: 3
From: Cheltenham, UK
I size up air blast coolers for hydraulic applications regularly. What you are saying is quite right, but it also depends on which region of the coolers heat dissipation capacity you were working, as the correlation between dissipation and air flow is certainly non linear. When you get to the top end you can throw as much air as you want but it won't make a blind bit of difference. Equally so you can double oil flow and you may even start going backwards as the heat generated by the pressure drop across the cooler is great than the increased capacity you hope to achieve.
Road Warrior
Joined: Nov 2008
Posts: 1,296
Likes: 3
From: Cheltenham, UK
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Supporter
Joined: Mar 2008
Posts: 4,419
Likes: 90
From: Vermont
Setting aside why you feel the need for an engineer or an oil cooler, where is this being installed on your bike? Can we have a photo or link, so we can size up the problem? deflecting debris using baffles is more desirable than part covering the cooler with a screen, I suggest.
