 linear flow dissoci ga linear flow dissoci ga equat planar two-dimension steadi flow ideal dissoci ga linear assum small disturb free stream chemic equilibrium exampl solut flow sharp corner superson stream evalu variat flow properti relax zone numer illustr provid 'oxygen-like' ideal ga comparison characterist solut flow sharp corner studi convent shock tube verifi theori experiment prove feasibl measur reaction rate ga mixtur 