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<DIV>Jim, </DIV>
<DIV> </DIV>
<DIV>I think Rex Lesher modified a True Turn spinner to have 'inlet slits' to
pull air into the spinner and back thru the motor. I don't know if there
were any tests to indicate if was effective. Maybe Rex can comment
here.</DIV>
<DIV> </DIV>
<DIV>I also believe there are some NASA airflow studies that indicate the area
around the prop hub and some small amount of the prop as well as the spinner
create an cone like airflow around that area that basically prevents air from
entering the spinner slots, etc.</DIV>
<DIV> </DIV>
<DIV>Hacker has a fan like attachment on the back of the large outrunners than
creates a negative pressure area inside the motor and draws air in thru the
front of the motor for cooling. there have been some tests retrofitting a
similar fan on the back of other outrunners with similar success.
Basically a trade off in weight for cooling effectiveness.</DIV>
<DIV> </DIV>
<DIV>As you know, I run an AXI 5330/F3A with the chin cowl opening ducted to
divert incoming air upward across the AXI. It seems to work even on the
hottest summer days. No air from the cheek cowls is ducted toward the
motor, it just passes thru toward the ESC and batteries.</DIV>
<DIV> </DIV>
<DIV>Don</DIV>
<DIV> </DIV>
<DIV>In a message dated 12/15/2006 4:14:26 P.M. Pacific Standard Time,
joddino@socal.rr.com writes:</DIV>
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<DIV>It would seem the best way to cool outrunners that have holes in the case
on the end that faces the nose ring, would be to bring air in through the
spinner and through holes in the backplate. Wondering if anyone has
really thought about the optimum design. I can picture internal vanes
but perhaps cutting off the nose of the spinner and leaving a big hole would
be adequate. Anyone tried anything like this?</DIV>
<DIV> </DIV>
<DIV>Jim
O</DIV><BR><BR>_______________________________________________<BR>NSRCA-discussion
mailing
list<BR>NSRCA-discussion@lists.nsrca.org<BR>http://lists.nsrca.org/mailman/listinfo/nsrca-discussion</FONT></BLOCKQUOTE></DIV>
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