The turboshaft engine performance is closely related to the helicopter’s design,
and because of its location beneath the helicopter’s main rotor, it has unique
features that distinguish it from other families of gas turbine engines. The
impact of the engine suction and main rotor’s blow in different flight regimes
and climatic conditions lead to variations in speed, pressure, and temperature
at the inlet of the turboshaft engines, which, in turn, will affect the design
of the engine cycle. Therefore, in this article, the equations governing the
airflow for turboshaft engines are enhanced to incorporate these effects. The
equations in this article are derived using aerodynamics, flight dynamics,
helicopter, and turboshaft design to lend the inlet velocity of the engine. In
order to validate the analytical outcomes of these equations, a computational
fluid dynamics (CFD) analysis is carried out to evaluate the turbulent flow at
the T700-GE turboshaft inlet. The analytical and numerical results comparisons
show a promising match that would allow future turboshaft engine designs to take
advantage of the proposed solution for the turboshaft engine’s inlet
velocity.
