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mgh

XML Brake TEMP?

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>It's the same formula to calculate heat generated. Identical.> Yet his is accurate and mine is not.>>By all means, explain.The point isn't the structure of the formula itself (three values multiplied together). It's which values get multiplied together... and how to interpret the result. To get a physically meaningful result, the middle value has to be a force, and the result should be interpreted as power.Alternatively, we can drop strict physics and introduce a "fudge factor" constant in place of the coefficient of friction, but we then need to be mindful that we can't attach any real physical meaning to this constant.Cheers,Martin

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Yea high, right I'm the guy with the question.As far as what is helping the original poster - me - Ed and Bill and Martin in order from greatest to least are the ONLY ones helping so everyone else being this my post I'd ask unless you can give me the XML code that I can put in or better than there is no need for everyone to become self proclaimed moderators of my thread. Thx but no thx.And yet I'm still left without a diffient answer can I put a formula into XML code so that FS gives me a partical figure I'm not looking for perfection but something believable.The funny thing is every where I asked for panel help they always told me one thing: Avsim Panel Design Forms - they're great you'll get the best help and they're really awesome people. For the most part it's all a big let down.2nd Lt. Engjell BerishaGood Day!


Good Day,

Engjell Berisha

 

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Hi Engjell,good to see you're still around -- I thought we'd lost you! ;)Sorry, I can't contribute any actual XML code -- all of the gauge programming I've done has been in C. But I'm sure someone else will be able to help you out -- this is a great place with great technical discussion, which is the reason I come here. It's rare that a thread derails like this one has in places...Cheers,Martin

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Perhaps Bill can offer XML based on Martin's completed formula.


Ed Wilson

Mindstar Aviation
My Playland - I69

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>And yet I'm still left without a diffient answer can I put a>formula into XML code so that FS gives me a partical figure>I'm not looking for perfection but something believable.>>The funny thing is every where I asked for panel help they>always told me one thing: Avsim Panel Design Forms - they're>great you'll get the best help and they're really awesome>people. For the most part it's all a big let down.Enjell,Perhaps if you could state what the output of the brake temp variable should look like, in other words, how does the value behave, it would be much easier to cobble together some XML code that will present a reasonable facsimile of the 'real deal.'Some type of description similar to the B757 example would be most helpful... ;)


Fr. Bill    

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>>Some type of description similar to the B757 example would be>most helpful... ;)>The B757 does not have a direct reading of brake temp but instead uses the energy added (liberated) by a single stop, measured in millons of foot pounds, and directly translates this value to an index from 0 to 9, which can be readed in lower EICAS. Also there is a cooling time that derives from the same table (actually there are two tables, one for steel and another for carbon brakes). Mostly depends on gross weight, ground speed, autobrake status and other variables, a really complicated stuff to port into an XML formula, unless an XML 2Dtable is coded with the most significant values for each variable. Maybe something of this kind could be adapted to what is needed in this case.Tom

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As for what I need the C-17 display gives an exact temperature reading in Celcius.


Good Day,

Engjell Berisha

 

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Okay I found the answer on my own. I decieded to take out my A310-304ET by HNAC and dust it off a bit because I hadn't flown it in a while. So I took it out for an approach at Telluride, CO. Anyway while I taxi I was going a bit fast for a turn so I gave it a little brake and at the corner of my the right ECAM screen turns to the wheels page and there I have EXACTLY what I was looking for the brake temperature in degrees celcius, a perfect hit. So I go to the panel folder and I find the file: Status.xml - from HNAC. And here's the code I found on the brake part:----- Brakes Indication ----- %((L:BrakeTemp_L,celsius))%!3.0d!%((L:BrakeTemp_L,celsius))%!3.0d!%((L:BrakeTemp_L,celsius))%!3.0d!%((L:BrakeTemp_L,celsius))%!3.0d!(A:BRAKE LEFT POSITION,percent) 5 > (A:LEFT WHEEL RPM,rpm) 30 > & if{ (L:BrakeTemp_L,celsius) (A:LEFT WHEEL RPM,rpm) 500 / + (>L:BrakeTemp_L,celsius) } els{ (A:AMBIENT TEMPERATURE,celsius) (L:BrakeTemp_L,celsius) < if{ (L:BrakeTemp_L,celsius) 0.1 - (>L:BrakeTemp_L,celsius) } els{ (A:AMBIENT TEMPERATURE,celsius) (>L:BrakeTemp_L,celsius) } } (A:BRAKE RIGHT POSITION,percent) 5 > (A:RIGHT WHEEL RPM,rpm) 30 > & if{ (L:BrakeTemp_R,celsius) (A:RIGHT WHEEL RPM,rpm) 500 / + (>L:BrakeTemp_R,celsius) } els{ (A:AMBIENT TEMPERATURE,celsius) (L:BrakeTemp_R,celsius) < if{ (L:BrakeTemp_R,celsius) 0.1 - (>L:BrakeTemp_R,celsius) } els{ (A:AMBIENT TEMPERATURE,celsius) (>L:BrakeTemp_R,celsius) } } %((L:BrakeTemp_R,celsius))%!3.0d!%((L:BrakeTemp_R,celsius))%!3.0d!%((L:BrakeTemp_R,celsius))%!3.0d!%((L:BrakeTemp_R,celsius))%!3.0d!- So that's that I'll put it into my C-17 panel in the Surfaces page of the MFD once I've got it properly tweaked down.The only issue I have right now is that the brakes change very quickly, so they'd cool and heat real quick. Also I tried gunning the engines and holding the brakes with no reaction on the temperature for about ten minutes I held it and the brake temp remained constant. Also the C-17 has more gear than the A310 so I'm gonna have to figure that out also.Anyway any help on the above and nothing more is appreciated.2nd Lt. Engjell BerishaGood Day!


Good Day,

Engjell Berisha

 

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If the brakes are heating too quickly, try increasing the "500" in the following piece of code to a greater value (for both the left and the right brake, of course).If the brakes are cooling too quickly, try reducing the "0.1" to a smaller value.

	<Value>(A:BRAKE LEFT POSITION,percent) 5 > (A:LEFTWHEEL RPM,rpm) 30 > & if{ (L:BrakeTemp_L,celsius)(A:LEFT WHEEL RPM,rpm) 500 / + (>L:BrakeTemp_L,celsius) } els{(A:AMBIENT TEMPERATURE,celsius) (L:BrakeTemp_L,celsius) <if{ (L:BrakeTemp_L,celsius) 0.1 - (>L:BrakeTemp_L,celsius) }els{ (A:AMBIENT TEMPERATURE,celsius) (>L:BrakeTemp_L,celsius)} }		   (A:BRAKE RIGHT POSITION,percent) 5 > (A:RIGHTWHEEL RPM,rpm) 30 > & if{ (L:BrakeTemp_R,celsius)(A:RIGHT WHEEL RPM,rpm) 500 / + (>L:BrakeTemp_R,celsius) }els{ (A:AMBIENT TEMPERATURE,celsius) (L:BrakeTemp_R,celsius)< if{ (L:BrakeTemp_R,celsius) 0.1 -(>L:BrakeTemp_R,celsius) } els{ (A:AMBIENTTEMPERATURE,celsius) (>L:BrakeTemp_R,celsius) } }	</Value>

>Also I tried>gunning the engines and holding the brakes with no reaction on>the temperature for about ten minutes I held it and the brake>temp remained constant.Hm, not sure what you mean here... was the aircraft moving while you were doing this, or was it standing still? If it was standing still, you wouldn't expect the brake temperature to increase...Cheers,Martin

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Hi,You can also try something like, (not tested, no functioning flightsim on my computer anymore, always complete crash!): (A:BRAKE LEFT POSITION,percent) 5 > (A:LEFTWHEEL RPM,rpm) 30 > and if{(L:BrakeTemp_L,celsius) C + (A:LEFT WHEEL RPM,rpm) 500 / min (>L:BrakeTemp_L,celsius) } els{(L:BrakeTemp_L,celsius) C - (A:AMBIENT TEMPERATURE,celsius) max (>L:BrakeTemp_L,celsius) }Experiment with C, 0.1 --> 0.01(?)Jan"Beatus ille qui procul negotiis..."

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>>- So that's that I'll put it into my C-17 panel in the>Surfaces page of the MFD once I've got it properly tweaked>down.>Well, this is a perfect example for what a simple solution that is completely out of reality indeed suits the programmer's requeriments.After all, this in nothing more than a simulation :-)Glad you finally found what you were looking for.Tom

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As for the stand still gunning the engines I would expect the brakes to get hot because they're is heat being created because the plane is trying to go forward at max power but the brakes are applied and preventing this so that thrust is being converted to head via the brakes I just don't know how to fix that.


Good Day,

Engjell Berisha

 

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Guest jahman

> As for the stand still gunning the engines I would expect the brakes to get hotEnergy is force times distance.This means if the wheels don't move (the distance is zero) the energy released will also be zero and the brake temperature will remain unchanged (or keep tending towards OAT, depending on the degree of realism implemented by your model).Cheers,jahman.

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"a simple solution that is completely out of reality indeed suits the programmer's requeriments"No further comment.

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