For the turbine characteristics expressed by taking the nozzle pressure ratio as the abscissa

the corrected mass flow and efficiency as the ordinate

and differentiated by different equal rotation speed lines

when the turbine works at critical state

the corrected mass flow of this form of turbine characteristics almost remain unchanged

and had the disadvantage of reducing computational efficiency in solving common working point when it was used in aeroengine mathematical model by interpolation of turbine characteristics. According to similarity theory and the corresponding relationship between turbine expansion work and nozzle pressure ratio under isentropic conditions

the calculation formula between turbine nozzle pressure ratio

turbine efficiency and turbine equivalent work was derived; combined with the parabolic interpolation method

a method for transforming turbine characteristics expressed in the above form was presented

the converted turbine characteristics were expressed by the equal rotation speed as the abscissa

the turbine equivalent work and efficiency as the ordinate

and differentiated by different equal corrected mass flow lines. The conversion calculation shows that with the proposed conversion calculation method

the relative error is less than 0.65% between two forms of turbine characteristics

which meets the engineering requirements

and can effectively avoid the disadvantage of previous turbine characteristics.