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Article
Publication date: 1 February 2022

Premkumar P.S., Nadaraja Pillai S. and Senthil Kumar C.

Pusher configured turbo-prop aircraft receive inadequate ram air cooling due to the lack of propeller slipstream, particularly during ground operations. However, flow entrainment…

Abstract

Purpose

Pusher configured turbo-prop aircraft receive inadequate ram air cooling due to the lack of propeller slipstream, particularly during ground operations. However, flow entrainment can be exploited to a greater extent by placing the oil-cooler duct close to downstream of the propeller at a suitable radial location. But this method has a detrimental effect on the propeller thrust. The purpose of this paper is to discuss the results of numerical simulations carried out to simulate the performance of the propeller with and without oil cooler.

Design/methodology/approach

In this paper, three-dimensional (3D) numerical simulations are carried out to simulate the propeller in a rotating domain using an unstructured grid. A computational fluid dynamics solver is put forward to analyze the effect of thrust loss by solving 3D Navier-Stokes equations using a second-order upwind finite-volume scheme. In this study, the impact of thrust loss incurred in the propeller flow field with and without oil cooler duct for three different locations at various rotational speeds is carried out to assess the propeller performance and to identify the optimum position to get a sufficient mass flow rate.

Findings

The findings from this study are simulated thrust values of an uninstalled five-bladed propeller of light transport aircraft (LTA) match well with original equipment manufacturer propeller thrust data. The tip speed velocities simulated for different operating conditions are in good agreement with the theoretical calculations. The influence of oil-cooler effect on the propeller flow field is less in low velocity to high-velocity operating condition due to flow transition from laminar to turbulent. The presence of the oil cooler, which influences the thrust loss, is studied at propeller upstream and downstream locations in detail for 30%, 40% and 50% of propeller radius cases.

Research limitations/implications

Simulations with finer and structured hexa grids can be applied to this problem to get closer results and save solver time as future work.

Practical implications

The recommended system is installed in the production standard aircraft of LTA. After installation oil cooler performance is better compared to the previous arrangement.

Originality/value

Research work about pusher aircraft is very limited. The problem addressed in this study is unique which resolves the major issue of pusher aircraft. This work highlights the difficulty involved in LTA engine oil cooling, and solution methodologies are also provided. Numerical simulation with oil-cooler assembly is a new area of research that gave the solution for this oil-cooling issue through various oil-cooler case studies.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 11 May 2015

Waqas Khan and Meyer Nahon

The purpose of this paper is to develop a physics-based model for UAV propellers that is capable of predicting all aerodynamic forces and moments in any general forward flight…

1066

Abstract

Purpose

The purpose of this paper is to develop a physics-based model for UAV propellers that is capable of predicting all aerodynamic forces and moments in any general forward flight condition such as no flow, pure axial flow and pure side flow etc.

Design/methodology/approach

The methodology adopted in this paper is the widely used Blade Element Momentum Theory (BEMT) for propeller model development. The difficulty arising from the variation of induced flow with blade’s angular position is overcome by supplementing the BEMT with the inflow model developed by Pitt and Peters. More so, high angle of attack aerodynamics is embedded in the simulation as it is likely for the blades to stall in general forward flight, for example during extreme aerobatics/maneuvers.

Findings

The validity of the model is demonstrated via comparison with experiments as well as with other existing models. It is found that one of the secondary forces is negligible while the other is one order of magnitude less than the primary static thrust, and as such may be neglected depending on the level of accuracy required. On the other hand, both secondary moments must be considered as they are of similar order of magnitude as the primary static torque.

Research limitations/implications

The paper does not consider the swirl component of the induced flow under the assumption that it is negligible compared to the axial component.

Originality/value

This paper fulfills the identified need of a propeller model for general forward flight conditions, and aims to fill this void in the existing literature pertaining to UAVs.

Details

International Journal of Intelligent Unmanned Systems, vol. 3 no. 2/3
Type: Research Article
ISSN: 2049-6427

Keywords

Article
Publication date: 10 June 2021

Witold Artur Klimczyk

This paper aims to present a methodology of designing a custom propeller for specified needs. The example of propeller design for large unmanned air vehicle (UAV) is considered.

Abstract

Purpose

This paper aims to present a methodology of designing a custom propeller for specified needs. The example of propeller design for large unmanned air vehicle (UAV) is considered.

Design/methodology/approach

Starting from low fidelity Blade Element (BE) methods, the design is obtained using evolutionary algorithm-driven process. Realistic constraints are used, including minimum thickness required for stiffness, as well as manufacturing ones – including leading and trailing edge limits. Hence, the interactions between propellers in hex-rotor configuration, and their influence on structural integrity of the UAV are investigated. Unsteady Reynolds-Averaged Navier–Stokes (URANS) are used to obtain loading on the propeller blades in hover. Optimization of the propeller by designing a problem-specific airfoil using surrogate modeling-driven optimization process is performed.

Findings

The methodology described in the current paper proved to deliver an efficient blade. The optimization approach allowed to further improve the blade efficiency, with power consumption at hover reduced by around 7%.

Practical implications

The methodology can be generalized to any blade design problem. Depending on the requirements and constraints the result will be different.

Originality/value

Current work deals with the relatively new class of design problems, where very specific requirements are put on the propellers. Depending on these requirements, the optimum blade geometry may vary significantly.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 4 May 2012

Mengmeng Zhang and Arthur Rizzi

The goal for this paper is to bring the easy‐to‐use geometry drawing software RDS to a “solid” mesh, which could be analyzed and simulated in CEASIOM, to enhance both CEASIOM and…

Abstract

Purpose

The goal for this paper is to bring the easy‐to‐use geometry drawing software RDS to a “solid” mesh, which could be analyzed and simulated in CEASIOM, to enhance both CEASIOM and RDS's capabilities.

Design/methodology/approach

The RDSSUMO interface is developed based on the feature that both RDS and SUMO define their geometric model using cross‐sectional information, i.e. their “universe” shapes are close to each other.

Findings

The translation is automated and allows the engineer to easily modify and augment the geometry in the process. Two test cases are shown, with their high quality Euler mesh and CFD computations. The A321‐look‐alike test case tests the mesh quality for transonic aerodynamics, such as high‐speed trim and drag divergence; the twin‐prop asymmetric aircraft is a “diffi+cult” non‐conventional configuration analyzed for yaw stability in one‐engine out mode.

Practical implications

This paper shows that the CFD solutions based on solid grids could be obtained once the design is proposed and the RDS wire‐frame model is available. The aerodynamic properties can then be predicted in early design stage, which is very efficient for preliminary aircraft design.

Originality/value

This fast meshing tool could obtain “working” grids of a new design within hours.

Details

Aircraft Engineering and Aerospace Technology, vol. 84 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 8 February 2022

Mohamed Awad and Eike Stumpf

This research aims to present an aero-propulsive interaction model applied to conceptual aircraft design with distributed electric propulsion (DeP). The developed model includes a…

Abstract

Purpose

This research aims to present an aero-propulsive interaction model applied to conceptual aircraft design with distributed electric propulsion (DeP). The developed model includes a series of electric ducted fans integrated into the wing upper trailing edge, taking into account the effect of boundary layer ingestion (BLI). The developed model aims to estimate the aerodynamic performance of the wing with DeP using an accurate low-order computational model, which can be easily used in the overall aircraft design's optimization process.

Design/methodology/approach

First, the ducted fan aerodynamic performance is investigated using a low-order computational model over a range of angle of attack required for conventional flight based on ducted fan design code program and analytical models. Subsequently, the aero-propulsive coupling with the wing is introduced. The DeP location chordwise is placed at the wing's trailing edge to have the full benefits of the BLI. After that, the propulsion integration process is introduced. The nacelle design's primary function is to minimize the losses due to distortion. Finally, the aerodynamic forces of the overall configuration are estimated based on Athena Vortex Lattice program and the developed ducted fan model.

Findings

The ducted fan model is validated with experimental measurements from the literature. Subsequently, the overall model, the wing with DeP, is validated with experimental measurements and computational fluid dynamics, both from the literature. The results reveal that the currently developed model successfully estimates the aerodynamic performance of DeP located at the wing trailing edge.

Originality/value

The developed model's value is to capture the aero-propulsive coupling accurately and fast enough to execute multiple times in the overall aircraft design's optimization loop without increasing runtime substantially.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 27 September 2018

Miodrag Milenković-Babić

This paper aims to present the new information about propeller thrust force contribution to airplane longitudinal stability analysis.

Abstract

Purpose

This paper aims to present the new information about propeller thrust force contribution to airplane longitudinal stability analysis.

Design/methodology/approach

The method presented in this paper is empirical, shows how propeller thrust force derivative can be obtained and gives some additional information about misinterpretation of the propeller thrust effects that are present in the current literature.

Findings

New information about propeller thrust force contribution to airplane longitudinal stability analysis has been presented. This information should enable more precise insight in aircraft stability analysis and better understanding of the physical process that occurs during maneuver flight.

Practical implications

The information presented in this paper is new and specific to the propeller aircraft configuration. The methods used here are standard procedure to evaluating propeller thrust force derivative.

Originality/value

The information in this paper presents theoretical results. The method for calculating thrust force contribution to the airplane longitudinal stability is given depending on the propeller type and should enable good engineering results.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 9
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 March 1953

EUGENE B. JACKSON

Aeronautical research scientists of the National Advisory Committee for Aeronautics have in the last six years indexed 7,070 non‐security classified NACA research reports under…

Abstract

Aeronautical research scientists of the National Advisory Committee for Aeronautics have in the last six years indexed 7,070 non‐security classified NACA research reports under 458 different subject classification headings for a total of 18,619 subject entries. They further face the task of subject classifying over 400 similar research reports per year, plus the large number of security classified reports issued annually.

Details

Aslib Proceedings, vol. 5 no. 3
Type: Research Article
ISSN: 0001-253X

Article
Publication date: 1 June 2000

Hui Ma

This paper discusses the elimination of failure of Y12(IV) inconstant propeller speed, which prevented the aircraft manufacturer from being able to receive effective data which…

Abstract

This paper discusses the elimination of failure of Y12(IV) inconstant propeller speed, which prevented the aircraft manufacturer from being able to receive effective data which the FAA was going to inspect. Furthermore, it analyses the trouble and introduces three methods to eliminate it.

Details

Aircraft Engineering and Aerospace Technology, vol. 72 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 December 1959

Svetopolk Pivko

The operating conditions of a conventional aerofoil type propeller or helicopter rotor in both subsonic and supersonic regions are separately considered, in the absence of direct…

Abstract

The operating conditions of a conventional aerofoil type propeller or helicopter rotor in both subsonic and supersonic regions are separately considered, in the absence of direct shock and blade interference effects and other disturbances. The performance of a propeller or rotor is approximately predicted by applying the conventional strip‐type analysis and the results of the two‐dimensional aerofoil theory.

Details

Aircraft Engineering and Aerospace Technology, vol. 31 no. 12
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 December 1957

J.T., P.A.T.C., E.T., A.E.J. and D.B.S.

There are sixteen papers in the present volume, of which three are on photoelasticity, five on other means of making strain measurements, three on the use of electrical resistance…

Abstract

There are sixteen papers in the present volume, of which three are on photoelasticity, five on other means of making strain measurements, three on the use of electrical resistance strain gauges in structures and mechanisms, three connected with testing machines and two reviews.

Details

Aircraft Engineering and Aerospace Technology, vol. 29 no. 12
Type: Research Article
ISSN: 0002-2667

1 – 10 of 458