The maneuverability of the Sukhoi Su-30 at very high angles of attack (AoA) was remarkably appealing. Canard angle, in cooperation with aircraft wing, created a flow pattern whereby, in that position, the fighter still had as much lifting force as po...
Wind turbine blades experience excessive load due to inaccuracies in the prediction of aerodynamic loads by conventional methods during design, leading to structural failure. The blade element momentum (BEM) method is possibly the oldest and best-kno...
The continuous increase in wind turbine blade length raises a serious question about how to effectively reduce the blade mass. As one of the solutions, recently, some wind turbine manufacturers are moving towards longer blades with thicker airfoils....
Experiments with elastic flaps applied on a common airfoil profile were performed to investigate positive effects on lift and drag coefficients. An NACA0020 profile was mounted on a force balance and placed in a wind tunnel. Elastic flaps were attach...
Rotational effects are known to influence severely the aerodynamic performance of the inboard region of rotor blades. The underlying physical mechanisms are however far from being well understood. The present work addresses this problem using Reynold...
In this study, a new aerodynamic surface concept is introduced, which is a powerful vortex generator (PVG). It can delay the stall point in a low-wing aircraft. This delay leads to a significant increase in the CLmax of an aircraft. The results of th...
The surfing performance of two shortboard fin types with surface features were compared to a standard (control) fin with a smooth surface using dynamic computational fluid dynamics (CFD) simulations. The fins with surface features included designs wi...
The flow control capability (especially for separation control) of a dielectric-barrier-discharge plasma actuator (DBD-PA) has been investigated extensively. However, these studies have been conducted under ideal conditions, such as wind tunnels and...
A preliminary study of a horizontal-axis wind turbine (HAWT) design is carried out using a wind tunnel to obtain its aerodynamic characteristics. Utilization of data from the study to develop large-scale wind turbines requires further study. This pap...
This study explores the aerodynamic behavior of bioinspired airfoils under extremely low Reynolds number conditions, simulating those found in the Martian atmosphere. Modified NACA 0018 profiles with sinusoidal leading-edge tubercles were tested to a...
This study investigates dynamic stall mechanisms of a pitching NACA 0012 airfoil through high-fidelity computational fluid dynamics (CFD) simulations. The improved delayed detached eddy simulation (IDDES) method based on a sliding mesh system is cons...
Dynamic stall is a critical limiting factor for airfoil aerodynamics and a challenging problem for active flow control. In this experimental study, dynamic stall was measured by high-frequency surface pressure tapes and pressure-sensitive paint (PSP)...
In this paper, a thorough 2D unsteady computational fluid dynamic analysis was performed on a pitching airfoil to properly comprehend the dynamic stall and aerodynamic forces. The computational software ANSYS Fluent was used to solve the unsteady Rey...
Numerical study on flow separation control is conducted for a stalled airfoil with steady-blowing jet. Stall conditions relevant to a rotorcraft are of interest here. Both static and dynamic stalls are simulated with solving compressible Reynolds-ave...
It is well known that sail-assisted propulsion works under gradient wind conditions in the atmospheric boundary layer, and is an energy-saving device for fuel consumption. In order to study the aerodynamic characteristics of a wingsail in the atmosph...
Canard configuration on fighter planes is essential for regulating flow and the occurrence of vortex interactions on the main wing, one of which is to delay stall. Stall delays are useful when the aircraft is making maneuvering or short-landing. This...
Based on phase space reconstruction and fractal dynamics in nonlinear dynamics, a method is proposed to extract and analyze the dynamics of the rotating stall in the impeller of centrifugal compressor, and some numerical examples are given to verify...
The effects of leading edge radius on the static and dynamic stall characteristics of rotor airfoils are investigated. Initially, a parametric airfoil (PARFOIL) method is employed to generate four morphed airfoils with different leading edge radii ba...
Passive vortex generators (VGs) have been widely applied on wind turbines to boost the aerodynamic performance. Although VGs can delay the onset of static stall, the effect of VGs on dynamic stall is still incompletely understood. Therefore, this pap...
The purpose of this study was to investigate the effect of the air permeability of ski jumping suit fabric on aerodynamic characteristics. In the study, four types of fabric with different air permeabilities were installed onto a fabric-clothed ellip...
Rotational augmentation and dynamic stall have been extensively investigated on horizontal axis wind turbines (HAWTs), but usually as separate topics. Although these two aerodynamic phenomena mainly determine the unsteady loads and rotor performance,...
This work focuses its attention on possibilities to enhance the stability of an axial compressor using a casing treatment technique. Circumferential grooves machined into the case are considered and their performances evaluated using three-dimensiona...
A high-speed centrifugal pump is the key facility to deliver oil in an aero-engine. The stable operation is quite important to the safety of the engine. High-speed pump stability is essentially caused by the transient pressure pulsations excited by t...
This paper investigates the effect of the Dynamically Morphing Leading Edge (DMLE) on the flow structure and the behavior of dynamic stall vortices around a pitching UAS-S45 airfoil with the objective of controlling the dynamic stall. An unsteady par...
The symmetric flying wing has a simple structure and a high lift-to-drag ratio. Due to its complicated surface design, the flow field flowing through its surface is also complex and variable, and the three-dimensional effect is obvious. In order to v...
The humpback whale flipper tubercles have been shown to improve the aerodynamic coefficients of a wing, especially in stall conditions, where the flow is almost fully detached. In this work, these tubercles were implemented on a F1 front-wing geometr...
The characteristic of delayed airfoil stalls caused by the bio-inspired Wavy Leading-Edges (WLEs) has attracted extensive attention. This paper investigated the effect of WLEs on the aerodynamic performance and flow topologies of the airfoil through...
A series of wind tunnel tests were performed to investigate the effect of turbulent inflows on the aerodynamic characteristics of variously modified trough incident leading-edge-protuberanced (LEP) wing configurations at various turbulence intensitie...
This study aims to assess the dynamic stall of the wind turbine blade undergoing pitch oscillation (PO) and oscillating freestream (OF), respectively. Firstly, a thin-airfoil theoretical analysis was performed to differentiate between these two dynam...
The increasing scale of wind turbines introduces significant aerodynamic challenges at ultra-high Reynolds numbers and under conditions of low Mach number compressibility. The stall behavior, flow separation, and boundary layer transition are all sig...
In this work, an airfoil geometry optimized for vertical-axis wind turbine applications is presented. Different airfoil shapes have been analyzed with JavaFoil, a panel method software. Then, the results from the analysis have been used to optimize t...
This article presents an experimental investigation of a passive-adaptive slat concept, an aerodynamic control mechanism aimed at avoiding separation in the inwards region of a horizontal axis wind turbine blade. The passive-adaptive slat is designed...
This study examines how leading-edge inclination angles affect a two-stage centrifugal compressor’s aerodynamic performance using numerical and experimental methods. Five impellers with varied inclination configurations were designed for both s...
An experimental investigation regarding the dynamic stall of various swept wing models with pitching motion was performed to analyze the effect of sweep on the dynamic stall. The experiments were performed on a wing with a NACA0012 airfoil section wi...
Three-dimensional corner separation is common in axial compressors, which can lead to large flow loss and blockage especially when it evolves into the corner stall (open separation). In this paper, the evolution of the three-dimensional flow structur...
The 4R-UAV project aims to develop aerodynamically efficient and environmentally friendly UAVs based on the 4R Circular Economy principle. In this study, the feasibility of the application of PFCDs (Passive Flow Control Devices) was investigated for...
This research aimed to compare the conception rates among AI at 12, 24, and 36 h after estrus in cattle living in tie-stall barns in a tropical environment. The second study was to determine factors at insemination at 24 h after estrus, including sec...
This paper introduces the realization and wind tunnel testing of a novel variable camber wing equipped with compliant morphing trailing edges. Based on the aerodynamic shape and compliant mechanisms that were optimized in advance, a wind tunnel model...
Vertical-axis wind turbines (VAWTs) offer key advantages such as independence from wind direction, low manufacturing costs, and reduced noise levels, making them highly suitable for urban and offshore wind energy applications. Among various VAWT desi...
Combined blowing was performed on a Hybrid Wing Body (HWB) aircraft through wind tunnel testing at a Reynolds number of 1.75 × 106. The full cycle of separation and reattachment under the control of combined blowing was implemented using Comput...
Fixed-wing aircraft with vertical takeoff and landing capabilities need a lower speed and a higher lift during transition. To meet these needs, a tandem-channel wing layout has been developed, including a FLR (front wing lower than rear wing) configu...
11 June 2025
Systems based on the oscillating water column (OWC) principle are often equipped with Wells turbines as power take-offs (PTOs) to convert sea-wave energy. The self-rectifying nature of the Wells turbine represents a strength for such applications, wh...
An improved wavy twisted rudder (WTR) is proposed based on a previous study. The misalignment of the wavy and propeller centers and the computational work of the previous study are supplemented to determine the effectiveness of the developed wavy twi...
Ducted fans installed on vertical takeoff and landing vehicles experience significant ground effect during takeoff and landing. The aerodynamic characteristics of a ducted fan hovering and transitioning in the ground effect are studied using numerica...
When a laminar boundary layer is subjected to an adverse pressure gradient, laminar separation bubbles can occur. At low Reynolds numbers, the bubble size can be substantial, and the aerodynamic performance can be reduced considerably. At higher Reyn...
Drag reduction of riblets is one of the most important problems in drag reduction of non-smooth surfaces. In the past two decades, the use of riblets arranged along the flow direction to reduce frictional resistance has received considerable attentio...
This paper presents two novel automated optimization approaches. The first one proposes a framework to optimize wind turbine blades by integrating multidisciplinary 3D parametric modeling, a physics-based optimization scheme, the Inverse Blade Elemen...
Rotor airfoil design involves multi-point and multi-objective complex constraints. How to significantly improve the maximum lift coefficient and lift-to-drag ratio of rotor airfoil is a fundamental problem, which should be solved urgently in the deve...
In this work, we present the first three-dimensional (3D) computational investigation of wind turbine airfoils over 360° angles of attack to predict unsteady aerodynamic loads and vortex-shedding characteristics. To this end, static–airfoil...
1 July 2019
I was born in 1947 and had autism with speech delay until age four. I am now a college professor of animal science. Horse activities enabled me to make friends through a shared interest in horses. This paper describes the benefits that I experienced...
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