Temperature Rise Effect on Winding

Dear all,

First of all apologize me, I'm facing problem to explain theoretically with some formula with I've forgotten when I was in college :-) .We all know that temp rise in alternator could effect gaps between stator and rotor and in extreme ways could be flash over due to fail on insulation OR friction, in ASIA the ambient temp is 35 deg C and our customer need to test the genset with load 110% for 3 hours.

Could you explain to me with formula (it good again to remind me for old guy ;)) the relation between temp rise, gaps, winding ?

Thank you in advance

LS