平壁一维稳态热传导 at、2ta2t2t a a0 ax a az k A ax 00 t=t:x=lt=t kA平壁一维稳态热传导 L t2 ( ) 0, ; , 0 1 2 1 2 2 2 t t L k A q x t t x L t t x t = − = = = = =   t1 A q k q z t y t x t t * ( ) 1 2 2 2 2 2 2 +   +   +   =    