Heat Transfer and Determining the Proper Gap

AI Thread Summary
The discussion revolves around calculating the minimum distance between a hot pipe at 1100°F and a tank that must remain below 258°F, using convective heat transfer principles. The user references the heat transfer equation and seeks guidance on how to incorporate the distance between the pipe and tank into their calculations. They have consulted a fire protection expert and shared relevant equations but remain uncertain about the relationship between heat transfer from the pipe to the air and from the air to the tank. Key parameters such as air temperature, thermal conductivity, and heat transfer coefficients are provided, but the lack of a system diagram complicates the analysis. Overall, the user is looking for assistance in applying these concepts to ensure the tank's temperature remains safe.
DjDriftX
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I am struggling a bit with this problem:

I have a pipe with a constant surface temperature of 1100F.
I also have a tank which cannot reach a temperature higher than 258F.

I am trying to figure out the minimum distance between the two (in 80F air, which will be moving at a minimum of 5 ft/sec) to keep the tank below 258F.

I remember a little from my previous thermo class, but I haven't taken heat transfer yet.
Im assuming that the pipe to air heat transfer is convective defined by:

\stackrel{.}{Q} = h * A(Tenv - T(t))

However I'm not sure how the heat transfer from the pipe to the air will relate to the heat transfer from the air to the tank.
Any guidance would be really helpfulEDIT:
So i conferred with a fire protection friend who led me to these equations:
http://imgur.com/EvQPF.png
EvQPF.png


However I'm not sure how to involve the distance between the objects, or if its even possible.Relevant Information
Air (80 Deg F)--------------- 300 K
Thermal Conductivity (k)------0.025 W/(m*K)
Density----------------------1.1839 kg/m^3
Thickness (2in)---------------0.0508 m
R-value----------------------2.032
heat transfer coefficient (h)---50 W/(m2K)
(Range 10 - 100)
Surface Area-----------------0.00064516 m^2

Pipe Surface (1100 Deg F)-----866 K
 
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Without a diagram of the actual system, it seems impossible to address these questions.
 
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