orr-S。 ommerfeld equation (U-C)(Φ”-a2①)-U"Φ= (aRe)("-2a2Φ"+a4Φ) bc y=0u=v′=0=>Φ=0Φ′=0 y=∞u′=v=0=>Φ=0Φ′=0Orr-Sommerfeld equation (U-c)(’’ -2)-U’’= -i/( Re)(’’’’-2  2’’+  4) bc: y=0 u’=v’=0 => =0 ’=0 y= u’=v’=0 => =0 ’=0