39 正2 u-udu 12 (△u)pu)→(△u,) 正4 ∑n=∑1(u)p)→( 式(231)3N2/p(u灿 倒3 2N 3N 40 式(2-34) 2u 2u( ) ( ) ( ) ( ) i i 2u u 2u u 2 i i 2 q i u p u 121 n p u u u d u i i i i = − =  +− p39 正2 正4 式(2 -31) 倒 3   ( ) ( ) = = = =  N i 1 i i N i 1 2 q qi u p u 121 N n ( ) −   = vv p u du dy dx 3 NV N 2 22 q 2 2 q NV N = 2 2 NV −VV ( ) u i p40 式(2 -34) 1 ( ) u eu 2 e 1 p u − = 2 3 ( ) u i 2 3 2 3 2 u e 2 u e