Unconventional Propeller−Airframe Integration for Transport Aircraft Configurations

It is envisioned that the future generations of regional and short to medium-range aircraft employ a high level of propeller integration to achieve low-emission flight. The objectives of unconventional propeller installations include the enhancement of the airframe aerodynamic efficiency, increasing the propeller efficiency, improving cabin...

Aerodynamic Model Identification of the Flying V from Sub-Scale Flight Test Data

This paper presents the identification of the aerodynamic model of the "Flying-V", a novel aircraft configuration. The aerodynamic model is estimated using flight test data from a 4.6\% sub-scale model. The dataset includes longitudinal and lateral-directional maneuvers performed by both the pilot and the autopilot to excite the aircraft dynamic...

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

In this combined experimental and numerical study, the propeller–airframe aerodynamic interaction is characterized for an aircraft configuration with propellers mounted to the horizontal tailplane. The contributions of the propeller and airframe to the overall loading are distinguished in the experimental analyses by using a combination of...

Experimental Investigation of Over-the-Wing Propeller–Boundary-Layer Interaction

This experimental study focuses on the aerodynamic interaction between an over-the-wing (OTW) propeller and a wing boundary layer. An OTW propeller is positioned above the hinge line of a wing with a trailing-edge flap. Measurements are carried out with and without axial pressure gradients by deflecting the flap and by extending the flat upper...

Numerical Investigation of Propeller–Flap Interaction in Inclined Over-the-Wing Distributed-Propulsion Systems

In this study, unsteady RANS simulations are performed to investigate the effect of over-the-wing (OTW) propeller inclination on the aerodynamic interaction with a wing featuring a plain flap. A comparison to experimental data shows that the numerical approach is capable of modeling the wing and propeller separately and can capture the effect of...

Aerodynamic interaction between propellers of a distributed-propulsion system in forward flight

This article describes an experimental investigation of the aerodynamic interaction that occurs between distributed propellers in forward flight. To this end, three propellers were installed in close proximity in a wind tunnel, and the changes in their performance, flow-field characteristics, and noise production were quantified using...

Aerodynamic Performance of Wingtip-Mounted Propellers in Tractor and Pusher Configuration

Wingtip-mounted propellers are a promising solution for advanced propulsion integration on future (hybrid-)electric aircraft. Previous work has confirmed the favorable aerodynamic interactions between the propeller and the wing that occur for wingtip-mounted propellers in both tractor and pusher configuration. However, a direct comparison of the...

Engineering method to estimate the blade loading of propellers in nonuniform flow

Advances in aerodynamic and propulsive efficiency of future aircraft can be achieved by strategic installation of propellers near the airframe. This paper presents a robust and computationally efficient engineering method to estimate the load distribution of a propeller operating in arbitrary nonuniform flow that is induced by the airframe...

Aerodynamic Loads on an Aft-Mounted Propeller Induced by the Wing Wake

This paper presents an experimental and numerical study of the aerodynamic in-plane and out-of-plane loads of a propeller which are induced by the wake of an upstream wing impinging on the lower half of the propeller disk. A propeller was installed behind a wing model in a low-speed wind-tunnel and measurements were taken with an external...

Wingtip-Mounted Propellers: Aerodynamic Analysis of Interaction Effects and Comparison with Conventional Layout

Wingtip-mounted propellers installed in a tractor configuration can decrease the wing induced drag by attenuating the wingtip vortex by the propeller slipstream. This paper presents an aerodynamic analysis of the propeller-wing interaction effects for the wingtip-mounted propeller configuration, including a comparison with a conventional...

Aerodynamic Interaction Between an Over-the-Wing Propeller and the Wing Boundary-Layer in Adverse Pressure Gradients

This experimental study focuses on the aerodynamic interaction effects that occur between an over-the-wing (OTW) propeller and a wing boundary-layer. An OTW propeller is positioned above the hinge-line of a wing featuring a plain flap. The measurements are carried out with and without axial pressure gradients by deflecting the flap and by...

Aerodynamic Performance of an Aircraft Equipped with Horizontal Tail-Mounted Propellers

This paper presents an experimental and numerical study of the aerodynamic interaction between horizontal tail-mounted propellers and the airframe. A representative aircraft model was installed in a low-speed wind-tunnel and measurements were taken with an external balance to determine the effect of propeller installation on integral forces...

Aerodynamic Performance of a Wingtip-Mounted Tractor Propeller Configuration in Windmilling and Energy-Harvesting Conditions

Wingtip-mounted tractor propellers enhance aerodynamic performance by attenuating the wingtip vortex with the propeller slipstream and inducing a favorable upwash on the wing. However, the close coupling between propeller and wing means that wing performance may be degraded when the propeller produces negative thrust. This paper analyzes the...

Validation and comparison of RANS propeller modeling methods for tip-mounted applications

This paper examines the capability of a commercial RANS solver for the simulation of wingtip-mounted propellers. The applicability of actuator-disk and actuator-line models to reduce the cost of propeller modeling is investigated in its most accurate form, by extracting and applying propeller blade loading from full-blade simulations. The...

Aerodynamic interaction effects of tip-mounted propellers installed on the horizontal tailplane

This paper addresses the effects of propeller installation on the aerodynamic performance of a tailplane featuring tip-mounted propellers. A model of a low aspect ratio tailplane equipped with an elevator and a tip-mounted propeller was installed in a low-speed wind-tunnel. Measurements were taken with an external balance and surface pressure...

Design and Analysis of an Installed Pusher Propeller with Boundary Layer Inflow

Boundary Layer Ingestion is an integrated propulsion concept in which a propulsor operates in boundary layer flow instead of the free streamflow with the goal to reduce the fuel flow for a given operating condition. The objective of this thesis is to obtain a better understanding of the power benefit of an installed pusher propeller at the aft...