Ivan Kostić, Dragoljub Tanović, Olivera Kostić, Ahmed Ali Irhayim Abubaker and Aleksandar Simonović
Unmanned aerial vehicles (UAV) with remote and/or automated flight and mission controls have replaced airplanes with pilots in many important roles. This study aims to deal with…
Abstract
Purpose
Unmanned aerial vehicles (UAV) with remote and/or automated flight and mission controls have replaced airplanes with pilots in many important roles. This study aims to deal with computational fluid dynamics (CFD) analysis and development of the aerodynamic configuration of a multi-purpose UAV for low and medium altitudes. The main aerodynamic requirement was the application of the tandem wing (TW) concept, where both wings generate a positive lift and act as primary lifting devices.
Design/methodology/approach
Initial design analyses of the UAV’s aerodynamic configuration were performed using ANSYS Fluent. In previous work in Fluent, the authors established a calculation model that has been verified by experiments and, with minor adjustments, could be applied for subsonic, transonic and supersonic flow analyses.
Findings
The design evolved through eight development configurations, where the latest V8 satisfied all the posted longitudinal aerodynamic requirements. Both wings generate a substantial amount of positive lift, whereas the initial stall occurs first on the front wing, generating a natural nose-down stall recovery tendency. In the cruising flight regime, this configuration has the desired range of longitudinal static stability and its centre of pressure is in close proximity to the centre of gravity.
Practical implications
The intermediate development version V8 with proper longitudinal aerodynamic characteristics presents a good starting point for future development steps that will involve the optimization of lateral-directional aerodynamics.
Originality/value
Using contemporary CFD tools, a novel and original TW aerodynamic configuration have evolved within eight development stages, not being based on or derived from any existing designs.
Details
Keywords
V.M. Jyothy and G. Jims John Wessley
In this study, 2D density-based SST K-turbulence model with compressibility effect is used to observe the flow separation and shock wave interactions of the flow. The wall static…
Abstract
Purpose
In this study, 2D density-based SST K-turbulence model with compressibility effect is used to observe the flow separation and shock wave interactions of the flow. The wall static pressure and Mach number differences are also evaluated. This study aims to discuss the aforementioned objectives
Design/methodology/approach
This study outlines the evaluation of the performance of a 2D convergent–divergent nozzle with various triangular jet tab configurations that can be used for effective thrust vectoring of aerial vehicles.
Findings
From the study, it is seen that the shadow effect induced by the tab with a height of 30% produces higher oblique wave deflection and higher thrust deflection at the exit nozzle. The numerical calculation concluded that thrust vector efficiency of 30% jet tab is, 0.46%. In the case of 10% jet tab height the thrust vector efficiency is higher, i.e. 1.647%.
Research limitations/implications
2D study.
Practical implications
The optimization will open up a new focus in TVC that can be implemented for effective attitude control in aircrafts.
Social implications
Used in future aircrafts.
Originality/value
The influence of shadowing ratio with different tab heights at different Mach numbers has not been reported in the previous studies. Few of the studies on jet tab are focused on the acoustic studies and not pertaining to the aerodynamic aspects. The multi jet configuration, the combination of location, shapes and other parametric analysis have not been covered in the previous studied.