Greetings ,

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 ?
Or
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 .
Great .
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 :


Great ,
The exact opposite as the text .
Exactly
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

The crew heater tower on panther g is closed off with pie slice panels when the crew heating is in effect. So it is not using atmosphere pressure, but using Fan induced pressure. Of course this has to reduce the effectiveness of the radiators it is attached to.

Yeah .
I didn't say that .
I said what you described

I'm not a Panther expert so bash me over the head if I am completely wrong.
The first page 51: The only suspect word is 'drawn', the rest is very clear about the fan pushing air through the pipe. Fan sucks air downward.

The second page 51 and page 52: I find this section unclear concerning the air direction. Where does the "already warmed" cooling air from the exhaust jackets come from ? Did the fans push air through the radiators before some of it went into the cooling jackets??
The later section implies that the fans are sucking air out from the bottom of the engine compartment. Fan is blowing upwards, at least in the later part of the text. First section describes the unwanted situation before reversing the fans ?

Page 60: Heat buildup was drawn off through rectangular channels ending in the right fan compartment.
I read this to mean that the fans are pulling air from the brakes -> fan is blowing upward ( at least the right side fan)

Page 125, diagram: Fan is sucking air through the jacket and blows it upwards. Does this apply to both fans at this time? Exhaust jacket is only connected to one of the fans (right or left ??) Diagram seems to indicate fan on the right side.

Page 160: The end situation is that the fan is blowing upward (warm air is produced by pulling air through the radiators and then directing a portion of it into the fighting compartment).
The main issue here is which situation the word 'reversed' refers to.
1. Was only the right side fan reversed to solve the engine room issues and exhaust jackets?
2. Does the text refer to the initial situation, i.e before solving the engine room issues ? Both fans blowing down

Point 1 or 2 could explain the confusing text.
This happens quite often, something is introduced in one part of the text and then a later section refers to the situation before the changes in the earlier section.

/ Robin

Thanks for responding , Robin

All I can say is I was very succinct in the breakdown of the text .
Respectfully ,
many of your conclusions contradict the text .

In a nutshell - the isometric drawing of the exhaust manifold cooling air flow direction is WRONG .

If we assume the air flow was changed from flowing DOWN and through the radiators and out the rectangular grates ,
to UP to provide " suction " for engine compartment scavenging and later heating air for the crew ,
What is the last paragraph about changing the direction on the LEFT fan for the heater operation if flow was already in that direction ?

Hard to align this rear end with the drawing of the exhaust jacket ......

I just gave my reading of the text and I agreed with your interpretation of it, even though I phrased it differently.

The question about the last paragraph assumes that the text is consistent with itself. If the word 'reverse' refers to the original design, i.e. before any of the other changes had been made then it makes some kind of sense, if we assume that the last paragraph has taken the first reversal of the air flow into consideration then it gets strange.
Is it certain that both fans had their rotation changed when the exhaust jacket flow was changed ? I assume that the exhaust jacket, being on only one side of the tank is connected to only one fan (the one on the left side, drawing is incorrect).

"In doing so, the fan wheel of the left fan group was driven in the reverse direction"
What is the 'reverse direction' in this case? Opposite to the original, as designed, direction or reverse in relation to the redesigned direction ?

In which order were the changes introduced ? Heater before exhaust jacket change, the other way around or both at the same time?

/ Robin

Yep ,
Those are the questions .
The chronology of it all

I'm waiting for a Panther Overlord to chime in

I think we agree the drawing is back-wards with the air-flow ?
. .. I'm sure that thing is plastered all over the internet .
adding to the confusion

and I don't understand why the cooling jacket would be only on one manifold - seems those exhaust pipes flanking the left tail-pipe would be coming from each side , no ?
That set-up was for testing ? It got fielded that way didn't it ?

I don't trust that drawing .
I've banished it from my mind

I think we can agree the crew compartment heater tower on panther G can only work when the left hand fan blew upwards.

The heating arrangement on panther A in my humble opinion works as the diagram indicated, where ambient air is drawn through the rabbit ear ducts on either side of left hand exhaust stack, and sent through the counter flow heat exchanger that is the manifold jacket. How the suction is developed to draw the ambient air in is harder to say as it is not illustrated. But I think it could be drawn in using Venturi suction on the blown side of the fan. Part of the air blown downwards by the fan can be drawn off into a Venturi tube. The air accelerates through a narrow constriction. This uses Bernoulli principle to drop air pressure, which creates the Venturi effect to draw air in.

Since we're talking German hardware, original documentation was in German. Therefore we always must take into account the possibility of translation issues. If you have some original texts in German, I'm willing as a German native speaker - to translate them...
Cheers

Chuk4 - that's not a crew heater .
There ain't no venturi on the Panther (except the pitot tubes used for the air-speed gauges - - -and some venturi flow in the carburetors )

Nicholas ,
I have taken into account translation issues -- I'm thinking a lot of the book's issues are a result of the translation and re-formatting ,
But this line of questions isn't dependent on that .

The fans blow upwards according to this-https://www.youtube.com/watch?v=WH2IYgTJc-E

Hummmmmm

Surviving Panzer V Panther Tank at the German Tank Museum.
Why has it got the cooled exhaust on the right side ?




Has one of the images above been mirrored or not ?
Look closely at the small openings/covers.
Somehow someone has moved the cooled exhaust pipe from one side to the other.

From WW II In color:


/ Robin

The rabbit ear intakes on either side of left hand exhaust? My understanding is those are intakes for a counter flow heat exchanger that utilizes the exhaust to heat the incoming air which are used to warm the fghting compartment.

The loader's hatch is still on the right ...
and the hull penetrations are the same . Not mirrored

They probably screwed up during the restoration. Or it was done as an in-joke.

I like the oil stain under the engine. It shows the thing can run.

NO
the applicable text is in the OP

If the OP text is correct and the rabbit ear pipes are for cooling exhaust manifold, why does only one manifold need cooling? It's a V-12 and should have separate exhaust manifold for each cylinder bank. The diagram show the flow covers only one manifold.

Did you read anything that I wrote ?

Maybe this could be of interest
http://www.motorbooks.at/lkw/militaria/panzerkampfwagen-panther-werkstatthandbuch-zum-maybach-motor-hl-230-p-30-und-hl-210-p-30

But maybe it doesn't say anything about the rest of the installations .......

/ Robin

Maybe this image from Twitter (someone restoring an engine) could give some information??


https://twitter.com/sturmi1975/status/592422811232292866
But maybe it's the wrong engine ? Seems to have exhaust cooling jackets on both sides ....

That's just an engine manual , Robin

I'm having a hard enough time with the German on all the included drawings in Spielberger's book -- I don't want a full German-text book

... but that reminds me , I asked in the forum in the past - What does the 30 in the P 30 represent ?

You could e-mail me scans and I'll translate

P30 vs P45:
"Die HL 230 Variante P45, wie sie aus dem Tiger bekannt ist, unterscheidet sich durch andere Nebenaggregate vom P30 und es war möglich, einen P30 zum P45 oder einen P45 zu einem P30 umzubauen. Charakteristisch für den P45 sind die runden Wirbelöl-Luftfilter."

Different auxiliary equipment. Swapping stuff would turn a P30 into a P45 and vice versa. P45 had circular (or round) air-filters

P45


P30





Images located on this German page:
http://www.fahrzeuge-der-wehrmacht.de/Artikel/Motoren.html

.. So it's like an ASTM # or the like ?
The 30 or 45 don't represent a quantity like the 210 and 230 do for displacement ?

I'll take you up on the translation offer !

Same engine (bore & stroke et.c), only some of the bolted on stuff was different ...

PM me for e-mail adress.
/ Robin

Well, why would only one manifold need cooling by active circulation?

The other engines seems to have had cooling on both sides so the question is why did the one version have cooling on only one side? Maybe something to do with where the fuel lines are?
Both exhausts get hot. Check
Fuel on hot exhaust pipe = bad idea. Check
Do we need to fix both exhausts? Maybe not absolutely necessary ... Hey guys! Lets do a quickfix for the most urgent problem.

Just guessing, ... but there was a war going on and the Panthers were wanted at the front in a reasonably working condition.

/ Robin