The two main tools are:
Actuator disc code - relates the thrust and power for an actuator disc in an incompressible fluid using momentum theory:
[P,etaProp,Vi,etaIdeal] = actuatordisc('computeP',T,rho,A,V,etaDisc)
[T,etaProp,Vi,etaIdeal] = actuatordisc('computeT',P,rho,A,V,etaDisc)
Specific fuel consumption code - calculates gas turbine power specific fuel consumption as a function of altitude, Mach number, and throttle setting:
[PSFC,eProd,e] = CALCULATEPSFC(h,M,throttle,assumptions)
In addition, an example engine deck function is provided with an included example:
[Tavail,TSFC,fuelFlow,etaProp,eCoreTotal,eCore] = DEMOENGINEDECK(Pshaftsls,fanArea,h,M,Treq,assumptions)
Finally, three assumptions functions are included that provide reasonable estimates for variations in efficiency and power lapse. These assumption function are straightforward to modify to incorporate your own assumptions:
POWERLAPSE determines the amount of power available from a gas turbine engine as a function of flight altitude and Mach number.
ALTITUDEEFFICIENCY estimates change in gas turbine core thermal efficiency as a function of altitude.
THROTTLEEFFICIENCY estimates change in gas turbine efficiency as a function of throttle setting.