Off-design characteristics of low-fuel consumption gas turbine engine for long-range UAV

UAVs are becoming of always greater importance, both for civil and military uses. Some UAV missions require a flight length of many hours, sometimes lasting more than two days. In these cases, the engine fuel consumption characteristics become of primary importance. In this sense, it is interesting to study the effects of some techniques, as intercooling and regeneration, on the engine power and fuel consumption, in particular in a turboprop engine, commonly used for this kind of missions. These effects have been studied by means of a thermodynamic numeric program that simulates the behavior of a turboprop engine with intercooling and regeneration, or with regeneration only. The program allows to do a parametric study, computing the main engine characteristics, as thermal efficiency, specific power and specific fuel consumption, for different operating conditions. After the parametric study, an off-design analysis has been performed, to see how the main engine parameters change.