heat transfer under tank

[monopoly]

Hi all,
We design foundations of the oil tanks (diameters vary from 30-55m, height 12-13m) sitting on gravel foundation. and the problem come to decide if we use geotextile as a secondary liner of the tank below 5 feet depth of gravel fill, if the tank bottom temperature constantly 90 degree celcius, which temperature can geotextitle experience for chosing the right type of geotextile?
Any sugestion for solution of the 1D axisymetric heat transfer since I am not familiar with HT problem? or any experience with this kind of configuration. And I guess I have to know the thermal resistance of the gravel fill, right? any range of value can be use?

 

[prex]

A simple google with e.g. 'gravel fill heat thermal resistance' will give you a lot of references, calculation methods and values. See for example thermal conductivity of gravel (close to 2.5 w/m°C). A slightly lengthier google (that I hope you'll do yourself next time ) gives the heat resistance of an object on the surface of a semi infinite body.

prex

http://www.xcalcs.com

: Online engineering calculations

http://www.megamag.it

: Magnetic brakes for fun rides

http://www.levitans.com

: Air bearing pads

 

[chicopee]

Based on the links by prex, I got a geotextile temperature of 183.8 dF or 84.4 dC for a 55m dia tank