Thermal problems that exist in airborne structure/ circuit ?

[singhj15]

i think its to with temperature,
, more advanced aircrafts

please help

 

[WimRFP]

Could you take some additional time to describe your problem/challenge better?

 

[singhj15]

Could you take some additional time to describe your problem/challenge better?

I have to do 5 minute talk on this, this is all they have told me.

I think its the thermal conductivity materials that are used on PCB to conduct heat and pass to heat sink. would just like to know how does difffer from sea level to when its airborne

 

[WimRFP]

Air is thinner (barometric height formula), this reduces heat transfer. Other thing related to PCB design is the breakdown voltage, so clearances need to be larger (look for Paschen curve).

 

[dick_freebird]

High performance airframes would prefer to do without
elaborate cooling. Refrigerant / heat pump systems are
a primary point of failure and contribute a lot of weight
(look up SWAP and SWAPC). You can forget forced air
cooling internal to the "boxes" as these tend to be
required to be environmentally sealed for various other
reliability dicta.

So what you are left with, as a minimum, is internal
conductive with -maybe- internal passive heat pipes,
but more usually thermal planes and thermal rails at
the individual board level and an good-as-practical
interface to the box walls where all heat will be shed.

This means the core of each board is an unhappy place
and designers jockeying for the superior peripheral
locations where heat can be better ejected.