27,467 research outputs found
K. S. Wing #4
No full textOne of four basic K. S. Wing designs. Stainless steel wire core covered with molded natural rubber. No cervical threads. In this design, the arms have been extended from the bulbed ends of design #2. "Wing" is stamped into the rubber on the stem
Optimal design of a composite wing structure for a flying-wing aircraft subject to multi-constraint
No full textThis thesis presents a research project and results of design and optimization of a composite wing structure for a large aircraft in flying wing configuration. The design process started from conceptual design and preliminary design, which includes initial sizing and stressing followed by numerical modelling and analysis of the wing structure. The research was then focused on the minimum weight optimization of the /composite wing structure /subject to multiple design /constraints. The modelling, analysis and optimization process has been performed by using the NASTRAN code. The methodology and technique not only make the modelling in high accuracy, but also keep the whole process within one commercial package for practical application.
The example aircraft, called FW-11, is a 250-seat commercial airliner of flying wing configuration designed through our MSc students Group Design Project (GDP) in Cranfield University. Started from conceptual design in the GDP, a high-aspect-ratio and large sweepback angle flying wing configuration has been adopted. During the GDP, the author was responsible for the structural layout design and material selection. Composite material has been chosen as the preferable material for both the inner and outer wing components. Based on the derivation of structural design data in the conceptual phase, the author continued with the preliminary design of the outer wing airframe and then focused on the optimization of the composite wing structure. Cont/d
Effect of wing flexibility on aircraft flight dynamics
No full textThe purpose of this thesis is to give a preliminary investigation into the effect of wing deformation on flight dynamics. The candidate vehicle is FW-11 which is a flying wing configuration aircraft with high altitude and long endurance characteristics. The aeroelastic effect may be significant for this type of configuration. Two cases, the effect of flexible wing on lift distribution and on roll effectiveness during the cruise condition with different inertial parameters are investigated.
For the first case, as the wing bending and twisting depend on the interaction between the wing structural deflections and the aerodynamic loads, the equilibrium condition should be calculated. In order to get that condition, mass, structure characteristics and aerodynamic characteristics are estimated first. Then load model and aerodynamic model are built. Next the interaction calculation program is applied and the equilibrium condition of the aircraft is calculated. After that, effect of wing flexibility on lift parameters is investigated. The influence of CG, location of lift and location of flexural axis are investigated.
The other case is to calculate the transient roll rate response and estimate the rolling effectiveness of flexible aircraft, and compared with the rigid aircraft’s. A pure roll model is built and derivatives both for the rigid wing and the flexible wing are estimated. It has been found that flexible wing leads to the loss of control effectiveness, even cause reversal when reduces the structure natural frequency. The influence of inertia data for flexible roll is also investigated
K. S. Wing #2
No full textOne of four K. S. Wing designs. Stainless steel wire core covered with molded natural rubber. No cervical threads. Bulbed ends. The arms are notched. "N S-2" is stamped into the rubber on the stem. We assigned the #2 based on the order of images in the Population Report in which it was described
allison-wing/RCEMIP-II: v1.1
No full text<p>This repository contains analysis scripts needed to reproduce the figures in Wing, A. A., Silvers, L. G., and Reed, K. A.: RCEMIP-II: Mock-Walker Simulations as Phase II of the Radiative-Convective Equilibrium Model Intercomparison Project, Geosci. Model Dev. Discuss. [preprint], https://doi.org/10.5194/gmd-2023-235, in review, 2023 which describes the RCEMIP-II protocol.</p>
<p>The anaylsis code is written in Matlab, compatible with Matlab version R2019b. </p>
Optimal design of a flying-wing aircraft inner wing structure configuration
No full textFlying-wing aircraft are considered to have great advantages and potentials in
aerodynamic performance and weight saving. However, they also have many
challenges in design. One of the biggest challenges is the structural design of
the inner wing (fuselage). Unlike the conventional fuselage of a tube
configuration, the flying-wing aircraft inner wing cross section is limited to a
noncircular shape, which is not structurally efficient to resist the internal
pressure load. In order to solve this problem, a number of configurations have
been proposed by other designers such as Multi Bubble Fuselage (MBF),
Vaulted Ribbed Shell (VLRS), Flat Ribbed Shell (FRS), Vaulted Shell
Honeycomb Core (VLHC), Flat Sandwich Shell Honeycomb Core (FLHC), Y
Braced Box Fuselage and the modified fuselage designed with Y brace
replaced by vaulted shell configurations. However all these configurations still
inevitably have structural weight penalty compared with optimal tube fuselage
layout. This current study intends to focus on finding an optimal configuration
with minimum structural weight penalty for a flying-wing concept in a preliminary
design stage.
A new possible inner wing configuration, in terms of aerodynamic shape and
structural layout, was proposed by the author, and it might be referred as
‘Wave-Section Configuration’. The methodologies of how to obtain a structurally
efficient curvature of the shape, as well as how to conduct the initial sizing were
incorporated.
A theoretical analysis of load transmission indicated that the Wave-Section
Configuration is feasible, and this was further proved as being practical by FE
analysis. Moreover, initial FE analysis and comparison of the Wave-Section
Configuration with two other typical configurations, Multi Bubble Fuselage and
Conventional Wing, suggested that the Wave-Section Configuration is an
optimal design in terms of weight saving. However, due to limitations of the
author’s research area, influences on aerodynamic performances have not yet
been taken into account
Influence of wing kinematics on aerodynamic performance in hovering insect flight
No full textThe influence of different wing kinematic models on the aerodynamic performance of a hovering insect is investigated by means of two-dimensional time-dependent Navier–Stokes simulations. For this, simplified models are compared with averaged representations of the hovering fruit fly wing kinematics. With increasing complexity, a harmonic model, a Robofly model and two more-realistic fruit fly models are considered, all dynamically scaled at Re = 110. To facilitate the comparison, the parameters of the models were selected such that their mean quasi-steady lift coefficients were matched. Details of the vortex dynamics, as well as the resulting lift and drag forces, were studied. The simulation results reveal that the fruit fly wing kinematics result in forces that differ significantly from those resulting from the simplified wing kinematic models. In addition, light is shed on the effect of different characteristic features of the insect wing motion. The angle of attack variation used by fruit flies increases aerodynamic performance, whereas the deviation is probably used for levelling the forces over the cycle.Aerospace Design, Integration and OperationsAerospace Engineerin
allison-wing/RCEMIP-II: v1.2
No full text<p>This repository contains analysis scripts needed to reproduce the figures in Wing, A. A., Silvers, L. G., and Reed, K. A.: RCEMIP-II: Mock-Walker Simulations as Phase II of the Radiative-Convective Equilibrium Model Intercomparison Project, Geosci. Model Dev. Discuss. [preprint], https://doi.org/10.5194/gmd-2023-235, in review, 2023 which describes the RCEMIP-II protocol.</p>
<p>The anaylsis code is written in Matlab, compatible with Matlab version R2019b. </p>
<p>v1.2: Updated plot_mockwalker.m to correct daily precipitation plotting error.</p>
Conceptual design and optimization methodology for box wing aircraft
No full textA conceptual design optimization methodology was developed for a medium range box
wing aircraft. A baseline conventional cantilever wing aircraft designed for the same mis-
sion and payload was also optimized alongside a baseline box wing aircraft. An empirical
formula for the mass estimation of the fore and aft wings of the box wing aircraft was
derived by relating conventional cantilever wings to box wing aircraft wings. The results
indicate that the fore and aft wings would use the same correction coe cient and that
the aft wing would be lighter than the fore wing on the medium range box wing aircraft
because of reduced sweep.
As part of the methodology, a computational study was performed to analyze di erent
wing/tip n xities using a statically loaded idealized box wing con guration. The analy-
ses determined the best joint xity by comparing the stress distributions in nite element
torsion box models in addition to aerodynamic requirements. The analyses indicates that
the rigid joint is the most suitable.
Studies were also performed to investigate the structural implications of changing only
the tip n inclinations on the box wing aircraft. Tip n inclination refers to the angle the
tip n makes to the vertical body axis of the aircraft. No signi cant variations in wing
structural design drivers as a function of tip n inclination were observed.
Stochastic and deterministic optimization routines were performed on the baseline box
wing aircraft using the methodology developed where the variables were wing area, av-
erage thickness to chord ratio and sweep angle. The conventional aircraft design showed
similar performance and characteristics to the equivalent in-service aircraft thereby pro-
viding some validation to the methodology and the results for the box wing aircraft.
Longitudinal stability investigations showed that the extra fuel capacity of the box wing in
the ns could be used to reduce trim drag. The short period oscillation of the conventional
cantilever wing aircraft was found to be satisfactory but the box wing aircraft was found
to be unacceptable hence requiring stability augmentation systems. The eld and
ight
performance of the box wing showed to be better than the conventional cantilever wing
aircraft. Overall, the economic advantages of the box wing aircraft over the conventional
cantilever wing aircraft improve with increase in fuel price making the box wing a worthy
replacement for the conventional cantilever wing aircraft
Preliminary fuselage structural configuration of a flying-wing type airline
No full textThe flying-wing is a type of configuration which is a tailless airplane accommodating all of its parts within the outline of a single airfoil. Theoretically, it has the most aerodynamic efficiency. The fuel consumption can be more efficient than the existed conventional airliner. It seems that this configuration can achieve the above mentioned requirements.
According to these outstanding advantages, many aircraft companies did a great deal of projects on the flying-wing concept. However, the application was only for sport and military use; for airliner, none of them entered production.
FW-11 is a flying-wing configuration airliner which is a design cooperation between Cranfield University and Aviation Industry Corporation of China (AVIC). Aiming the spatial economic and environmental needs, this 200-seat airliner would attract attention from airline companies for cost saving and environmental protection.
Before start, this program is designated for a new generation commercial aircraft to compete with the existing same capability airliner, such as Airbus A320 and Boeing 767. As the first team of this program, the aim is to finish the conceptual design and prepare the relevant document for next two teams that will perform preliminary and detail design.
As a member of FW-11 program and as part of the GDP, the author has been through the four conceptual design stages: engine manufacturers, aircraft family issues, structure design and the establishment of 3-D CAD model.
The aim of IRP study is to focus on the initial fuselage design
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