GENENG : A generic turboprop engine model

This report describes GENENG, a code developed t o model the performance of a generic turboprop engine. Using published data from various sources, a database of 7 turboprop engines suitable for General Aviation, Commuter & Regional transport aircraft was developed. This database consists of the values of the SHP available, Fuelflow, and Jet Thrust produced by the engines at specific altitudes between sea-level and 35000 ft and forward speeds between 0 and 350 knots (TAS), at max. take-off, max. Climb & max. Cruise ratings. GENENG can then be used to obtain realistic estimates of any of these three parameters for a generic engine that lies within this database at any operating condition, i.e. altitude, forward speed, and engine rating. The user has to specify the ball-parking criterion, i.e. the desired value of any one of the three parameters at a specific operating condition. The generic engine is then positioned in the database, by identifying the nearest two engines at the ball-parking criterion. The fractional ratio of the location of the generic engine from these two engines is then calculated. Assuming that the same fractional ratio would also apply at all the other data points, the values of all the parameters at all engine ratings are then generated at specific combinations of forward speed and altitude. Using Bicubic Spline interpolation routines, the value of any of the three parameters at any forward velocity and altitude can then be obtained.