So back when I first started investigating the Panther , one of the first things I was researching was the crew compartment heater operation .
Simple enough to understand but very tied to the direction of airflow through the fans
I obtained Spielberger's Panther and it's Variants and immediately found confusing , seemingly contradictory info through-out the book .
I had pretty much forgotten about all this until I came across an older thread over at Missing-Lynx late last night concerning the manifold cooling air and concomitant pipes that flank the left exhaust pipe .
The thread was a mess . Full of confusion --- but I understand why .
Does the fan spin counter-clockwise , drawing air through the flanking radiators and blowing the heated air straight up skywards ?
Does the fan spin clockwise and push the air through the heat exchangers ( radiators ) ?
The fans are shaft driven , 2-speed gearbox for winter and summer cooling requirements and incorporate a clutch within the fan hub to absorb rapid torque inputs from engine acceleration .
I can find no text or schematics which indicate rotation direction , so airflow direction must be inferred .
Let's infer :
Page 51 :
So the fan is supplying the work .
We're on the high pressure side of the fan .
The fan is blowing DOWN and we're scavenging some of this air at ambient temperature and pushing it around the exhaust pipes and out the back with all that heat and exhaust .
Classic set-up .
Text-book arrangement .
Now , same page ,
page 51 -52 :
Ah - so now the fan has been reversed .
The fan is blowing UP .
The underside of the fan is now the low pressure side and we are utilizing it to scavenge explosive vapors from the engine compartment .
A decrease in efficiency in the cooling system since we are now reliant on the atmospheric pressure to push cooling air thru our heat exchangers --- the delta-P , difference in pressure ,provided by the fan . Less efficient .
BUT NO MORE FIRES -- good trade-off .
Page 60 :
... this one is push , to me , for fan direction .
It would be better for the fan to be exhausting upward so this does not lower the temperature difference between the coolant and air ... but . whatever .
It's a less than poor way to transfer the heat .
We know there is no air " flow " since the cooling system compartments are fully sealed to be flooded for forging so it's crap conduction at best .
But - there's a war on , you do what do .
Page 125 :
The exact opposite as the text .
This set-up is stupid , contradicts the text and I'm convinced it's a "typo " .
Here of course the fan blows UP , not down , to provide the " suction "
Now - the crew compartment heater just directs a portion of the air heated by the left radiators back down through the engine compartment and thru the fire-wall to the fighting compartment via a dedicated duct .
So the air must be flowing UP for this to work .
If you change the flow direction in that one schematic , you're left with the fans initially blowing DOWN and through the radiators ( ideal situation )
Then changed to blowing upwards to ventilate the engine compartment and provide discharge air for the crew heater .
and then on page 160 :
SO . Uh
so they are blowing downward now and the left side is reversed to blow upward .
The left side blows UP and the right side blows DOWN ?
Of course ,, how ?
Seems fitting a reverse-pitch impeller would be the easiest method .
Maybe they switch out a gear ...
Any and all info and clarification to all this appreciated