Method and apparatus for electronically determining nozzle throat area and harmonics

摘要

A method of determining the throat area between adjacent airfoils in a nozzle set among a plurality of nozzle sets of a machine involves providing a plurality of inspection points on a suction side of a first airfoil and a pressure side of a second airfoil, the second airfoil being adjacent to the first airfoil. A plurality of inspection points are provided on each of an outer sidewall and an inner sidewall, respectively, of the nozzle set. Positions of each of the first and the second airfoils, and the outer and inner sidewalls are determined by measuring the positions of the inspection points. The measured positions of each of the first and second airfoils, and the outer sidewall and the inner sidewall are compared with corresponding predetermined values. A finite area deviation of each of the suction side of the first airfoil, the pressure side of the second airfoil, the outer sidewall, and the inner sidewall are determined, and the individual components are combined to compute a total finite area deviation. A total known throat area is adjusted to offset for the total finite area deviation in order to determine a net total throat area.