http://www.fluidyne.com/pl_theoc.html 

 

 Really liked the DB 30517 (3.75" thick double pass model)  Will probably use this one on my -8.   

 

 Tracy   

 

Perhaps you mean use “two” instead of “this one”.  I looked closely (longingly) at the fluidyne when I was in the market for a cooler; but they just don’t make on with the capacity for the 20B.  One DB 30517 would handle neither the flow nor heat rejection needed; however 2 in parallel would do it.  At least that’s what my analysis says.

 

Al

 

 Nope, at least I don't think so.   Here's my take on it.  

 

The Mazda cooler has 180 CU In. core area and gives me enough cooling for the 13B.  I'm assuming for now that the dimensions for the Fluidyne are core area (must check) which give it 275 cu in, which is 153% of the Mazda.  Pretty good match, at least on paper.   The "effectiveness quotient"  for the Fluidyne at almost double the thickness is not as good but I'm hoping the much better ducting and pressure recovery on the -8 will cancel that out.  The higher delta T air temp will give less cooling drag, at least in my universe : )

 

In any case,  the main -8 mission calls for 100 HP at  >=18,000 ft.  It'll work.

 

 Tracy   (please don't ask me to define "effectiveness quotient")

 

I was over stating it a bit suggesting two to make the point; and it has a little more volume than I thought.  My old notes say about 230 cu. in. for that one; I think the dimensions they give include the end tanks.  Yeah; it’ll work at 100hp and 18000, but might be marginal getting up there.

I once had pressure drop flow data from Fluidyne, but guess I tossed it.  Might be worth checking.

 

Al