Today I did my ‘morning after’
check and cross check on my analysis of the flow data I presented yesterday. My
calculation of the flow through the core based on the exit velocity profile
wasn’t consistent with a check of diffuser ratio and average velocity . .
. short story is – I had made a mistake. I had compensated for the flow
area taken up by the tubes twice; once in each of two steps of the
calculations.
Making that correction, if the data is
to be believed, is that the calculated flow through the core is 93% of the air
approaching the entrance of the scoop. The flow distribution isn’t
the greatest, but considering that the outside two rows of fins where the flow
is slow have a tube on only one side, there isn’t much to be gained by a
better distribution.
I’ll be looking further into what
is then the mystery of why the cooling capacity is lower than expected.
Meanwhile, it appears that the oil/coolant heat exchanger is the plan of choice.
Maybe the reason the Lyc oil cooler
install worked so well was that the Lyc didnt need much cooling in the first
place
Not convinced that its a
useful reference point unless he did what you did and actually measured
pressure differential across the cooler.
Mike Wills
Mike;
I agree with your assessment. I
was looking forward to meeting you last Wed. Sorry you couldn’t make
it. Another time.
Al