Patent ID: 8083476

Claim:
A method of designing a multistage turbine for a turbomachine, each stage of the turbine comprising a stator row and a rotor row, each formed by an annular row of airfoils, each stator (or rotor, respectively) row having the same number of airfoils or a number that is a multiple of the number of airfoils of a row of the same type situated upstream, wherein the method consists, for all of the stator or rotor rows: a) modifying simultaneously the shape of the airfoils of the various rows to straighten out the wakes from the trailing edges of said airfoils over substantially the entire radial extent of the airfoils; and then b) angularly positioning the rows relative to one another in such a manner that the wakes from the stator (or rotor, respectively) rows of a stage n impact within a certain angular tolerance on the leading edges of the stator (or rotor, respectively) rows of a downstream stage n+1, so as to achieve multistage aerodynamic coupling simultaneously over the turbine as a whole.