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This paper aims to guide the implementation of noise reduction measures in hoistway and reduce the aerodynamic noise generated by elevator operation, this paper aims to propose an aerodynamic noise analysis method that can solve the flow field in hoistway.

A turbulence-acoustic model solving the flow field in a hoistway and a numerical wind hoistway model of the ultra-high-speed elevator were established by using large eddy simulation (LES) and Curle acoustic theory.

The characteristics of pulsating flow field and aerodynamic noise around ultra-high-speed elevator are analyzed. The asymmetric characteristics of the flow field could be observed using the turbulent kinetic energy and the instantaneous vortexes in the wind hoistway model. Vortex shedding, air flow separation and recombination around the car were the key factors for aerodynamic noise generation. The sound pressure level was approximately linear to the logarithm of car speed. The increase of car deflection angle in a certain range would reduce the peak frequency of wake noise and increase the sound pressure level (SPL) value.

This paper provides important guidance for researches studying the aerodynamic noise in the hoistway and the technical personnel that look for the reduction measures, which greatly improves the shortcomings in the numerical simulation of the aerodynamic noise of the hoistway.

The purpose of this paper is to present a fast, economical and practical method for mathematical modeling of aerodynamic characteristics of rectangular wing in ground (WIG) effect.

Reynolds averaged Navier–Stokes (RANS) equations were converted to Bernoulli equation by reasonable assumptions. Also, Helmbold’s equation has been developed for calculation of the slope of wing lift coefficient in ground effect by defining equivalent aspect ratio (ARe). Comparison of present work results against the experimental results has shown good agreement.

A practical mathematical modeling with lower computational time and higher accuracy was presented for calculating aerodynamic characteristics of rectangular WIG effect. The relative error between the present work results and the experimental results was less than 8 per cent. Also, the accuracy of the proposed method was checked by comparing with the numerical methods. The comparison showed fairly good accuracy.

Aerodynamic surfaces in ground effect were used for reducing wetted surface and increasing speed in high-speed marine and novel aeronautical vehicles.

The proposed method is useful for investigation of aerodynamic performance of WIG vehicles and racing boats with aerodynamic surfaces in ground effect.

The proposed method has reduced the computational time significantly as compared to numerical simulation that allows conceptual design of the WIG crafts and is also economical.

The sandy environment is one of the typical environments in which helicopters operate. Air-sand two-phase flow in sandy environments may be an important factor affecting flight safety. Taking a typical example, this paper aims to investigate the aerodynamic and rotor trim characteristics of the UH-60 helicopter in sandy environments.

A computational study is conducted to simulate the air-sand flow over airfoils based on the Euler–Lagrange framework. The simulation uses the S-A turbulence model and the two-way momentum coupling methodology. Additionally, the trim characteristics of the UH-60 rotor are calculated based on the isolated rotor trim algorithm.

The simulation results show that air-sand flow significantly affects the aerodynamic characteristics of the SC1095 airfoil and the SC1094R8 airfoil. The presence of sand particles leads to a decrease in lift and an increase in drag. The calculation results of the UH-60 helicopter rotor indicate that the thrust decreases and the torque increases in the sandy environment. To maintain a steady forward flight in sandy environments, it is necessary to increase the collective pitch and the longitudinal cyclic pitch.

In this paper, the aerodynamic characteristics of airfoils and the trim characteristics in the air-sand flow of the UH-60 helicopter are discussed, which might be a new view to analyse the impact of sandy environments on helicopter safety and manoeuvring.

The purpose of this paper is to describe the effects of characteristic geometric parameters on parafoil aerodynamic performance by using computational fluid dynamics (CFD) technique.

The main characteristic geometric parameters cover the planform geometry, arc‐anhedral angle, basic airfoil and leading‐edge cut. By using the CFD technique, a large number of numerical parafoil models with different geometric parameters are developed to study the correlations between these parameters and parafoil aerodynamic performance.

The CFD technique is feasible and effective to study the effects of characteristic geometric parameters on parafoil aerodynamic performance in three‐dimensional (3‐D) flowfield condition. The planform geometry can affect the aerodynamic performance obviously. An increase in arc‐anhedral angle decreases the lift of a parafoil but has little effect on lift‐drag ratio. The model with smaller leading‐edge radius and thinner thickness of parafoil section achieves larger lift‐drag ratio. The leading‐edge cut has little effect on lift but increase drag dramatically; meanwhile, its effect on flowfield is confined to the nearby region of leading edge.

The presented 3‐D numerical simulation results of parafoil models are shown to have good agreement with the tunnel test data in general trend; meanwhile, considering its relatively low‐cost, the CFD method could be further used to predict coefficients in pre‐research or at non‐experimental conditions.

The paper can form the foundation of further studies on parafoil aerodynamic performance with different geometric parameters.

This paper aims to deal with the experimental estimation of both longitudinal- and lateral-directional aerodynamic characteristics of a new twin-engine, 11-seat commuter aircraft.

Wind tunnel tests have been conducted on a 1:8.75 scaled model. A modular model (fuselage, wing, nacelle, winglet and tail planes) has been built to analyze both complete aircraft aerodynamic characteristics and mutual effects among components. The model has been also equipped with trailing edge flaps, elevator and rudder control surfaces.

Longitudinal tests have shown the goodness of the aircraft design in terms of aircraft stability, control and trim capabilities at typical clean, take-off and landing conditions. The effects of fuselage, nacelles and winglets on lift, pitching moment and drag coefficients have been investigated. Lateral-directional stability and control characteristics of the complete aircraft and several aircraft component combinations have been tested to estimate the aircraft components’ interactions.

The experimental tests have been performed at a Reynolds number of about 0.6e6, whereas the free-flight Reynolds number range should be between 4.5e6 and 9.5e6. Thus, all the measured data suffer from the Reynolds number scaling effect.

The study provides useful aerodynamic database for P2012 Traveller commuter aircraft.

The paper deals with the experimental investigation of a new general aviation 11-seat commuter aircraft being brought to market by Tecnam Aircraft Industries and it brings some material on applied industrial design in the open literature.

The purpose of this paper is to investigate the unsteady aerodynamic characteristics in the deflection process of a morphing wing with flexible trailing edge, which is based on time-accurate solutions. The dynamic effect of deflection process on the aerodynamics of morphing wing was studied.

The computational fluid dynamic method and dynamic mesh combined with user-defined functions were used to simulate the continuous morphing of the flexible trailing edge. The steady aerodynamic characteristics of the morphing deflection and the conventional deflection were studied first. Then, the unsteady aerodynamic characteristics of the morphing wing were investigated as the trailing edge deflects at different rates.

The numerical results show that the transient lift coefficient in the deflection process is higher than that of the static case one in large angle of attack. The larger the deflection frequency is, the higher the transient lift coefficient will become. However, the situations are contrary in a small angle of attack. The periodic morphing of the trailing edge with small amplitude and high frequency can increase the lift coefficient after the stall angle.

The investigation can afford accurate aerodynamic information for the design of aircraft with the morphing wing technology, which has significant advantages in aerodynamic efficiency and control performance.

The dynamic effects of the deflection process of the morphing trailing edge on aerodynamics were studied. Furthermore, time-accurate solutions can fully explore the unsteady aerodynamics and pressure distribution of the morphing wing.

This paper aims to present a literature review on analytical research on the prediction of aircraft spin and recovery characteristics, as it progressed from the early years of aviation to current state of the art spin technologies.

Aerodynamic model development approaches that have been generally used in past spin studies are presented. Past contributions in application of these analytical techniques to predict spin and recovery characteristics on various fighters, general aviation and airliners are discussed, thus providing useful reference for researchers embarking aircraft spin research. An overview of the development of spin prevention and spin recovery technologies to mitigate stall/spin susceptibility is presented.

The challenges associated with the presented techniques that prompt possible future research directions are discussed.

Despite considerable progress in the recent years, no comprehensive review on the analytical and computational research techniques to predict aircraft post-stall/ spin characteristics has been undertaken in the recent years.

The purpose of this paper is to present the preliminary design of a medium altitude long endurance (MALE) unmanned aerial vehicle (UAV), focusing on the interaction between the aerodynamic and the structural design studies.

The classic layout theory was used, adjusted for the needs of unmanned aircraft, including aerodynamic calculations, presizing methods and CFD, to estimate key aerodynamic and stability coefficients. Considering the structural aspects, a combination of layout, finite element methods and custom parameterized design tools were used, allowing automatic reshapes of the skin and the internal structural parts, which are mainly made of composite materials. Interaction loops were defined between the aforementioned studies to optimize the performance of the aerial vehicle, maximize the aerodynamic efficiency and reduce the structural weight.

The complete design procedure of a UAV is shown, starting from the final stages of conceptual design, up to the point where the detail design and mechanical drawings initiated.

This paper presents a complete view of a design study of a MALE UAV, which was successfully constructed and flight-tested.

This study presents a complete, synergetic approach between the configuration layout, aerodynamic and structural aspects of a MALE UAV.

The purpose of this paper is to understand the natural wind field characteristics of the tunnel entrance section and analyzing the aerodynamic performance of high-speed railway trains (HSRTs) under natural winds.

Three typical tunnel entrance section sites, namely, tunnel–bridge in a dry canyon (TBDC), tunnel–bridge in a river canyon (TBRC) and tunnel–flat ground (TF), are selected to conduct a continuous wind field measurement. Based on the measured wind characteristics, the natural winds of the TBDC and TF sites are reconstituted and imported into the two corresponding full-scale computational fluid dynamics models. The aerodynamic loads of the HSRT running on TBDC and TF with reconstituted winds are simply analyzed.

The von Kármán spectrum can be used to describe the wind field at the tunnel entrance section. In the reconstituted natural wind condition, a time-varying feature of wind speed distribution and leeward side vortex around the HSRT caused by the wind speed fluctuation is found. The fluctuating amplitude of aerodynamic loads at the TBDC infrastructure is up to 97.9% larger than that at the TF infrastructure.

The natural wind characteristics at tunnel entrance sections on the high-speed railway are first measured and analyzed. A numerical reconstitution scheme considering the temporal and spatial variation of natural wind speed is proposed and verified based on field measurement results. The aerodynamic performance of an HSRT under reconstituted natural winds is first investigated.

Development of the Lockheed supersonic transport has followed the basic philosophy that an advance in air travel in terms of speed and economics should be accompanied by similar advances in aeroplane safety and flying qualities. To achieve these objectives, Lockheed's SST design work has been concentrated for many years on the development of a fixed‐wing design. The present configuration—called a double delta—provides a simple high lift system with low wing loading, excellent low speed stability and control, and large favourable ground effects in landing, with inherent advances in operational simplicity and safety.