A review of advanced turboprop transport aircraft

Aerodynamic Performance and Static Stability Characteristics of Aircraft with Tail-Mounted Propellers

“…The relatively large propeller diameter compared with tailplane span leads to a change of the tailplane root vortex that causes the tailplane effectiveness to reduce with an inboard-up rotating propeller. M ODERN propellers are an attractive means of aircraft propulsion for short-to medium-range missions because of their inherent high efficiency compared with technology-equivalent turbofans [1][2][3][4][5][6][7][8][9][10][11]. Block fuel savings up to 20% have been anticipated for missions that are climb and approach dominated [4,[12][13][14].…”

“…The distribution of the overall sound pressure level inside the cabin is less concentrated because of various transmission mechanisms [30,34], and the highest interior noise level is typically located approximately one diameter downstream of the propeller rotation plane, near the wing-fuselage junction [25,30,34]. Alternatively to the passive shielding methods that have been investigated for these configurations [5,31,35], a larger reduction in perceived airborne and structureborne noise can potentially be achieved by mounting the propeller propulsion system to the tailplane or a pylon, as already proposed in the 1980s [1,4,6,9,21,30,36]. For such a aft-mounted propulsion arrangement, several additional advantages have been identified from an aerodynamic-efficiency perspective, such as the potential of an extended region of laminar flow on the wing [37], and reduced adverse compressibility effects on the wing and nacelle at flight Mach numbers up to 0.8 [38].…”

“…The wing had zero quarter-chord sweep, a taper ratio of 0.40, and an aspect ratio of 8.46. This aspect ratio of the model is relatively low compared with existing and envisioned turboprop aircraft, with aspect ratios ranging between 8 and 14 [1,9,[65][66][67][68][69]. The implication is that the downwash gradient of the aircraft model is relatively high.…”

Prediction of burning performance and emissions indexes of a turboprop motor with artificial neural network

“…The power generated in this type is transmitted by the drive shaft to the gearbox connected to the propeller that creates the thrust. This second type of turboprop engine is called a free turbine turboprop engine (Lange, 1986;Saravanamuttoo, 1987;Kerrebrock, 1992;Mattingly, 2006;Boyce, 2011).…”

Numerical simulation for the differences between FTN/WPN engine models aerodynamic influence on BWB300 airframe

“…FTN simulates only the outside shell with no power, and the air can flow through it, while WPN is used to simulate the powered engine's inflow and outflow influences by setting the appropriate inlet and outlet boundary conditions. The research of the engine influences on conventional transport aerodynamic by using FTN/WPN models has been going for decades now (Lange, 1986;Stankowski et al, 2017), but the corresponding research on BWB only emerged in the last few years. Recently, Boeing/NASA in its Environmentally Responsible Aviation (ERA) project has performed a series of research on the Ultra-High Bypass integration of HWB (Hybrid Wing Body, also referred to as the BWB) using both FTN/WPN models (Deere, Luckring, McMillin, Flamm, & Roman, 2016;Flamm, James, & Bonet, 2016;Schuh et al, 2016).…”