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ddawson

engine temp and cowl flaps

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Hi everyone, I have been beginning to mess about with XML guages, and have accoplished a few little things I needed, but now I have run into something that has me really stopped. The subject of my current current project has thermostatically controlled cowl flaps, so now I am trying to make a guage that will open and close the cowl flaps in relation to the engines temperature. The hotter the engine gets, the more they open etc. I think I am in over my head though, hehe.Does anyone have any ideas on how I could go about making something like this?Thanks in advance for any suggestions. Cheers

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If you wanted your cowl flaps to start opening at say 500 degrees and be completely open by 650 degrees (I'm picking numbers here...) then you have a formula that went something like:cowl_flap_pos1 = (egt - 500) / 150if cowl_flap_pos1 < 0 then cowl_flap_pos1 = 0if cowl_flap_pos1 > 0 then cowl_flap_pos1 = 1(K:COWLFLAP1_SET,cowl_flap_pos1)Same sort of routine for engine 2.Anyway, subtract your minimum temperature from your actual temperature. Divide the difference by the difference between minimum and maximum temperatures.As to the actual XML coding, I won't misguide you by making suggestions :-rollDoug Dawson

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Hi again. I know this post is old now, but after taking a break from sims for a bit I am now back at it again. I understand the idea behind the above formula, but my ability to put it into correct XML structure isnt so great.So I am wondering if someone can help me format it correctly?In the meantime, I did try doing it this way. (A:Eng1 cylinder head temperature,celsius) s0 110 > l0 300 < and if{ (>K:INC_COWL_FLAPS1) } els{ (>K:DEC_COWL_FLAPS1) }Basically this works, but the problem with doing it this way is that the moment the engine temp goes over the threshold the cowls instantly open fully.thanks again, I greatly appreciate the help.

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Hello Nautilus This is the code I am using to control Radiator doors on the cowls for Merlins.----------------------- (A:Recip eng1 radiator temperature,celsius) sp0 (L:Lgill,bool) if{ l0 115 > if{ 16383 (>K:COWLFLAP1_SET) } els{ l0 109 < if{ 0 (>K:COWLFLAP1_SET) } els{ l0 int 109 - 2731 * (>K:COWLFLAP1_SET) } } } els{ 16383 (>K:COWLFLAP1_SET) }--------------------------The (L:Lgill,bool) is the control switch 1= Auto and 0= Fully open.The range is 6 Celsius degrees with a door opening angle of 30 degrees and this equates to 6 steps of 17 KeyFrames in FSDS [0 to 102 really but make the last Keyframe '100' ], 5 angular degs. per. frame.It is still jerky but in smaller steps.If you want the whole gauge to play with, send me an e-mail.Regards Ted

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