How Much Nitrogen Vaporizes Daily from a Superinsulated Liquid Nitrogen Tank?

[walaa1989]

A certain superinsulation material having a thermal conductivity of 2*10[-][/4] w/m.c is used to insulate a tank of liquid nitrogen that is maintained at -196 c, 199 Kj, is required to vaporize each kilogram mass of nitrogen at this temp. assuming that the tank is sphere having an inner dia. (0.52) m, estimate the amount of nitrogen vaporized per day for an insulation thickness of 2.5 cm and an ambient temp. of 21 c, assume that the outer temp. of the insulation is 21 c.

 

[walaa1989]

need help?

 

[fresh_42]

Welcome to PF!

This thread is meant to be an introduction to yourself. It is not required that you use it at all.

However, your question looks like homework or some textbook exercise. In either case you are requested to use our homework section and the template there which automatically is inserted at the start of a post. It is important to do so, because it tells us which kind of solution you're after, i.e. which kind of formulas are allowed to use (part 2), and where exactly you got stuck (part 3, important!), so we could explain it specifically.
This is necessary as it certainly wouldn't make much sense to retype entire sections of textbooks.