Orr-Sommerfeld equation (u-c)("-a2d)-U= -i/(ae)(-2a2"+a4) bc: y=0u=v=0=>=0=0 y=∞=v=0=>Φ=0=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