Donald H Locker wrote:
>
> Actually, I would expect pushing to work better -- the turbulence
> generated by the fan will break down the stagnant layer of air near
> the heat transfer elements and effect a higher heat transfer
> coefficient. (M.E. and E.E. from U of Michigan)
I think the difference between pushing and pulling has to do more with the use
and type of shroud in the equation.
If no shroud is used and you are using a puller fan, the air is capable of
hitting all the front of the radiator.
If you put a pusher fan in front of the rad, it will only blow air through that
portion that the fan covers. Since no radiator is
round and no fans are square, that leaves some of the radiator not receiving
air from the fan.
This is where shrouds come in to play. If you surround the fan with a shroud
(whether it is behind or in front of the rad, it will
tend to pull or push sir through the entire radiator. Theoretically, you are
generating more force than is relieved by the area
immediately in front of (or behind) the fan.
I used two 10" fans on my Spit race car and mounted them in front with a shroud
that ensures that all air is directed at the radiator
and no air escapes around the fans. With that arrangement, I achieve the best
coverage possible.
I opted for the in front location mainly for ease of access for service.
Regards,
Joe
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