Speed of Heat

On Fri, 18 Mar 2005 at 23:27:50 in message
.net, Mike Rapoport
wrote:

I have flight manuals that give a correction for airspeed and altitude and
the numbers are much higher than 3C even though the speeds are below M0.5.
In the MU-2, the temp sensor is in the tail section where the cross section
of the fusilage is actually decreasing.. Is there both a compression and a
friction heating of surfaces due to airflow?

Of course; but I don't think the driving temperature can get higher than
the stagnation temperature. Let's try it for Concorde:

At 55,000 ft the outside standard air temperature is 217 deg K

So Ts = To(1 + (2.05^2)/5) = 408 == 126 C

That is very close to the value quoted in Brian Trubshaw's book about
Concorde. The chart on page 34 shows the nose temperature at 127 C, the
leading edge of the wing at 105 C, pilots cockpit area skin temperature
at 97C decreasing towards the rear fuselage at 91 C. Mind the fuel in
the wings kept down their temperature from rising too high!

It does not show the fins or air intakes but I doubt they were much
higher than the forward fuselage section just behind the nose at 100 C.
--
David CL Francis