Digital Simulator for Steady-State Performance Prediction of Military Turbofan Engine

Abstract

The signie cance of propulsion system steady-state performance prediction has been identie ed. The digital simulation techniques have been described for steady-state performance prediction, with component maps and a controller. In addition to performance prediction, the application of a simulation code has been demonstrated to an engine cycle redesigning case study without major modie cations in already existing hardware. As per the current military application trends, the twin-spool turbofan with a mixed exhaust has been chosen as the propulsion concept. The proposed formulation can easily be modie ed to simulate the steady-state performance of the twin-spool turbojet engine and also to generate the control schedules in the early design stage. Nomenclature A = area ALT = altitude CD = nozzle e ow blockage factor Cp = specie c heat F = thrust g = gravitational constant H = enthalpy J = Joule’ s constant M = e ight Mach number N = rotational speed P = total pressure PR = nozzle pressure ratio p = static pressure R = gas constant T = total temperature t = static temperature V = e ow velocity W = mass e ow rate D = change in quantity g = ratio of specie c heats h = component efe ciency u = nozzle petal angle Subscripts