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2016
This study investigated the performance of blown airfoil. Two types of blown airfoil were developed. The integrated parts of the airfoils were investigated in the subsonic wind tunnel to study the aerodynamic forces. Each airfoil was implemented with a blower at different locations on the upper surface and was tested in the wind tunnel, with different Reynolds numbers, and with and without blower. The results showed that the airfoil with air blower produced a very significant additional 35% lift force compared to airfoil without air blower. The experimental result also exhibited 7% higher lift coefficient for air blower compared to numerical analysis.
World Academy of Science, Engineering and Technology, International Journal of Environmental and Ecological Engineering, 2015
Airfoil plays an important role in any aircraft because it has to generate adequate lift to hold the aircraft in the air with less drag. The design of an airfoil with desired aerodynamic characteristics is not so easy till date. In early days the design was random and it was tested in a flow section, then Wright Brothers come with cambered section. NACA has given a proper definition for airfoil which help us to create airfoil using formulas and not randomly. In this work a detailed study of NACA 2312 airfoil, at various angle of attack and different free stream velocity in the wind tunnel. This work is divided into two phase one is numerical analysis and another one is experimental verification by fabricating the airfoil and testing in wind tunnel. The aerodynamic characteristics are plotted against AOA and the comparison between the numerical and experimental is also performed.
The flow characteristics over a symmetrical airfoil are studied experimentally in a low speed wind tunnel. The pressure distribution on the airfoil surface was obtained, lift and drag forces were measured and mean velocity profiles were obtained over the surface. Experiments were carried out by varying the angle of attack, from 0 o to 120 o and ground clearance of the trailing edge from the minimum possible value to free stream velocity region. It was found that high values of pressure coefficient are obtained on the lower surface when the airfoil is close to the ground. This region of high pressure extended almost over the entire lower surface for higher angles of attack. As a result, higher values of lift coefficient are obtained when the airfoil is close to the ground. The flow accelerates over the airfoil due to flow diversion from the lower side, and a higher mean velocity is observed near the suction peak location. The pressure distribution on the upper surface did not change ...
An airfoil is the shape of a wing or blade or sail as seen in cross-section. An airfoil-shaped body moved through a fluid produces an aerodynamic force. The airfoil designing is a critical task due to various dependent variables in design process. This article deals with simulation of new airfoil section design and comparing it with a standard baseline airfoil. The calculations of lift force are done for six cases for varying altitude, constant rotor and air stream velocity. The conclusions are drawn from the simulated results obtained after analysis which will be useful in design of airfoil.
This project describes the study of the effects of pressure, on the symmetric and unsymmetric type of airfoil, analyzing the lift, temperature, and the drag generated at zero angle of attack. The Joukowski series was used for both un-symmetric (High Camber) and the symmetric, which were tested in a sub-sonic wind tunnel, under basic atmospheric conditions. For larger sizes of airfoils, a foil simulator was used to generate the effects of pressure. It was observed that pressure variation, occurred as a result of the shape of the airfoil in both cases. Both profiles were discretized into small sections, analyzing different point effects, across the entire profile. Pressure drop across the profiles, caused an increase in the velocity, lift, and a reduction in drag, as the temperature varied only below the atmospheric condition at which the airfoil was subjected. From the experiment, it was obtained, that the symmetric airfoil, would be very effective for applications which require little drag, and a considerable average amount of lift (fans), but the un-symmetric would be very applicable for applications which require a very large amount of lift, where a propulsive system could be incorporated to compensate for the large amount of drag that would be generated from the airfoil (aircrafts).
International Journal of Renewable Energy Development, 2018
This study numerically investigated different types of high-performance airfoils in order to increase the efficiency of wind turbines. Performances of five airfoil types were numerically simulated at different attack angles (0 ° <α <20 °) and at different wind speeds (4, 8, 16 and 32 m/s). Numerical analysis shows that all airfoils achieve the highest performance at attack angles between 4o and 7o. Results also show that the performance of all airfoils increases in direct proportion to increase in wind speed with a low gradient. A new hybrid airfoil was generated by combining lower and upper surface coordinates of two high-performance airfoils which achieved the better results in pressure distribution. Numerical analysis shows that the hybrid airfoil profile performs up to 6% better than other profiles at attack angles between 4o and 7o while it follows the maximum performance curves closely at other attack anglesArticle History: Received January 16th 2018; Received in revised...
Continuous rise of energy demand and need for cleaner environment emphasizes efficient conversion of energy from renewable sources. Wind energy is the most viable sources of renewable energy and it is environmentally friendly alternative energy sources. Energy extraction from wind energy is rapidly competitive to power production from other sources like coal. In this paper, Computational Fluid Dynamics (CFD) is used to predict the aerodynamic efficiency of wind turbine blades. A blade's aerodynamic efficiency is expressed in terms of its lift-to-drag ratio. The design and analysis of blades is one of the critical areas of wind turbine design. In this paper, a review of aerodynamics of the two dimensional NACA 0015 airfoil for vertical axis wind turbine (VAWT) is attempted. The main focus of this investigation is to analyze the flow behavior around the airfoil body and to calculate the performance coefficients at velocity 10.5 m/s and angle of attack from 0° to 20°. Comparisons of the CFD results with numerical predictions from the XFOIL result and NACA report showed a good agreement.
2018
ABSTRACT: Constraints on aerodynamic noise are also becoming increasingly important. The fundamental design problem, common to all these disciplines, is to design a wing shape that provides the desired lift for given operating conditions, while at the same time fulfilling the design constraints. However, design optimization normally requires a large number of analyses of objectives and constraints. Consequently, a careful selection of computational methods, both for the fluid flow analysis and the optimization process, is essential for a fast and efficient design process. This papers provides an approach for determining the aerodynamics performance of different airfoils with some modifications. The two airfoils NACA 0012 and S2027 has been considered for the study. By cutting the end point to convert into flat surface, NACA 0012 airfoil has been modified in this work. The CFD analysis has been carried out along with experimental validations. Eddy viscosity Pressure, Lift, Drag, Diff...
SSRN Electronic Journal
This research represents the result of experimental study of aerodynamic coefficients, CL, CD, Cm, coefficients of pressure, CP, and flow field around NACA 0012 airfoil. An open loop subsonic wind tunnel, AF100, was used to conduct the experiment for two Reynolds number 10.15 104 and 15.23 104 and with different angle of attack-0 degree, 5 degree, 10 degree, 15 degree, 20 degree. Pitot tube was used to measure the flow velocity. Again, yawmeter was used to collect and calculated data of flow angularity around airfoil. The data of lift, drag and pitching moment were collected from VDAS for calculating CL, CD and Cm. Pressure coefficients Cp were calculated from the pressure readings of 20 pressure tappings around the midplane of the airfoil. The result shows that no lift is generated at 0 degree AOA, but with the increase of AOA, significant amount of lift and drag is generated. Vortex was found to occur at the trailing edge due to flow separation. The result shows that with the increasing AOA, flow separation region is getting increased. For greater Reynolds number, the phenomena is more prominent.
Lecture Notes on Multidisciplinary Industrial Engineering, 2019
A substantial amount of research has been performed on aerofoils [1-3] for years. It is used in the development of aircraft [4], windmills [5], wind turbines and such machineries operating in flow of air. On the suction side of a first-stage turbine vane, a study through experimentation was conducted by Ethridge et al. [1] for the investigation of the film-cooling performance. Dassen et al. [3] performed measurements in wind tunnel. It showed the self-noise of a series of flat plates and aerofoils with the teeth at the trailing edge of varying planforms and orientations in order to analyse for the case of more realistic flows and geometries the previously reported noise reducing potential of serrated trailing edges. Selig et al. [4] investigated a natural-laminar-flow aerofoil, the NLF (1)-0115, which had been designed for general-aviation aircraft at the NASA Langley Research Center. Majola [5] discussed the performance data of the Savonius rotor and established the design criteria. Angle-of-attack and shape are the predominant factors affecting the lift on an aerofoil [6]. Unlike cambered aerofoils generating lift at zero angle-of-attack, most aerofoils require a positive angle-of-attack for generation of lift. The circulation of air in the surroundings of the aerofoil creates curved streamlines due to which on one side lower pressure is formed and higher pressure on the other accompanied by a velocity difference, via Bernoulli's principle, so the flow field about the aerofoil resulting from this creates higher average velocity on one surface than on the other [7, 8]. Englar [8] found from experimental observations that 2D and 3D aerofoils employing nominal blowing demonstrated lift gain double to triple that of the conventional flapped aerofoil. The analysis for negative angles-of-attack is seldom performed, but the drag and lift coefficient for such positions are
International Journal for Research in Applied Science & Engineering Technology (IJRASET), 2022
In this project "Aerofoil Design and Analysis" an attempt has made to make a complete study on lift and drag coefficient of various aerofoil sections using CFD. The primary goal of this project is to learn and analyse the aerodynamic performance of wings. The objective of this study is to improve aerofoil design using the software CATIA, And Fluent Analysis using the software ANSYS. Aerofoil is a principal part of any airplane construction. How much lift force and drag force is sufficient to balance the weight of the plane is decided by the aerofoil. Aerofoils are basically divided into two categories-they are Asymmetrical and Symmetrical aerofoils. Based on their drag and lift coefficient's variation with angle of attack, stall angle of attack and magnitude of the coefficients they are divided. Here the NACA aerofoil is modified by adding dimples on the upper half of the wing and compared with the simple one. The comparison is made on different speed and pressure on the wing and the coefficient of lift and drag. I.
A wind tunnel test of baseline airfoil NACA 0015 model was conducted in the Wind tunnel wall test section of the Department of Mechanical Engineering at KUET, Bangladesh . The primary goal of the test was to measure airfoil aerodynamic characteristics over a wide range of Angle of Attack (AOA) mainly from Zero degree to 20 degree AOA and with a wind tunnel fixed free stream velocity of 12m/s and at Re = 1.89×10 5 . The pressure distribution in both upper and lower camber surface was calculated with the help of digital pressure manometer. After analysis the value of C l and C d was found around 1.3 and 0.31 respectively.
Advances in Science and Technology Research Journal, 2021
Improved Blowing and Suction System (IBSS) is a novel concept that can be effectively implemented in future aircraft to improve the aerodynamic performance of aircraft wings. The proposed IBSS consists of a regular wing without its secondary control surfaces and with a Pump. The injection and suction system is used to create additional flow without disturbing the main flow over the aerofoil which effectively delays the boundary layer separation. The injection and suction areas are kept constant and they are located just below the maximum thickness point and suction is created close to the trailing edge. This paper presents a detailed numerical analysis of the proposed IBSS and the study shows that the stalling angle of attack is increased by 60% while the coefficient of lift is increased 37.5% compared to the baseline aerofoil. Also, the commercially used coflow jet (CFJ) method stalls at a 12° angle of attack whereas with the proposed IBSS method the stall occurs at a 16° angle of ...
International Journal of Mechanical and Production Engineering Research and Development, 2020
In the current world almost all the aerodynamic bodies are designed and then analysed for preliminary results. These designs however need to be verified and tested in real time. To study various flow parameters and response of any aerodynamic body under varying conditions and orientations, wind tunnels are used. These tunnels are usually of open or closed types which can be used to conduct studies over flows past any aerodynamic body or structure. The work focuses on aerodynamics design of a Wind Tunnel to simulate and disseminate results of subsonic flows, measurement of lift coefficient (CL) and drag coefficients (CD) which can be used to determine performance of any aerodynamic body. The proposed tunnel was designed based on flow theories to obtain a preliminary design of subsonic tunnel. An open type wind tunnel is designed using CAD tool which is further simulated using ANSYS CFX. The CFD results are examined to decide an optimized design which is then fabricated to carryout experimentation. The model comprises of three parts namely contraction cone which is a convergent tract, test section and a diffuser commonly referred to as diverging tract. The wind speed of the tunnel is varied with the use of a variable transformer. The tunnel manufactured is used to study lift and drag forces acting on different aerodynamic structures and designs. The aerodynamic study of CLARK Y air foilis carried out for testing in wind tunnel after a standard calibration.
to study the effects of Air moving past to the solid objects. A wind tunnel testing machine consists of a closed tubular passage with the object under test mounted in the middle and powerful fan system moves air past to the object. The wing (airfoil) provides lift by creating a situation where the pressure above the wing is lower than the pressure below the wing. Since the pressure below the wing is higher than the pressure above the wing. The readings has been taken on airfoil model in Wind Tunnel Testing Machine (WTTM) at different air velocity 20m/sec, 25m/sec, 30m/sec and different angle of attack 0 0 ,5 0 ,10 0 ,15 0 ,20 0 . Air velocity and pressures are measured in several ways in wind tunnel testing machine by use to measuring instruments like Anemometer and Multi tube manometer. The Surface roughness of an airfoil is can be measure by Surface roughness tester. The heat signature of a testing model is can be measure by Thermal Imaging Camera. The CFD analysis is also carried out at various sections of airfoil angles and velocity. The maximum performance to the airfoil model is achieved at 10 0 on angle of attack.
2007 Annual Conference & Exposition Proceedings
This paper shows a course project in an undergraduate engineering program with a mechanical emphasis. The students used LabVIEW software for measurements of the pressure distribution on the surface of a Clark-Y airfoil at different angles of attack in a low-speed wind tunnel. Both the wind tunnel speed and the angle of attack of the airfoil were automatically controlled from the software. Furthermore, the LabVIEW software also controlled the Scanivalve solenoid for pressure measurements. The experiments were compared with computations using the CosmosFloWorks software.
Fre-and-aft symmetrical upper surface protrude lower surface concave (USPLSC) airfoils have been developed for the coaxial rotating wing of an UAV. In order to understand the aerodynamical performance of the airfoil, low speed wind tunnel experiment is carried out to measure lift coefficient, drag coefficient and pressure distribution under wind speed 20~40 m/s. Results are compared with CFD prediction using Fluent software. A satisfied agreement has been achieved and error analysis is provided. The purpose of this study is to conduct a parametric investigation on the performance of USPLSC airfoils for coaxial rotating wing UAV. The main objective of this study is to test USPLSC in wind tunnel and compare the experiment result with CFD simulation result.
Video abstract: https://www.youtube.com/watch?v=qR3Ac0kGV64
EPJ Web of Conferences, 2012
This paper is part of the development of an airfoil for an unmanned aerial vehicle (UAV) with internal propulsion system; the investigation involves the analysis of the aerodynamic performance for the gliding condition of two-dimensional airfoil models which have been tested. This development is based on the modification of a selected airfoil from the NACA four digits family. The modification of this base airfoil was made in order to create a blowing outlet with the shape of a step on the suction surface since the UAV will have an internal propulsion system. This analysis involved obtaining the lift, drag and pitching moment coefficients experimentally for the situation where there is not flow through the blowing outlet, called the no blowing condition by means of wind tunnel tests. The methodology to obtain the forces experimentally was through an aerodynamic wire balance. Obtained results were compared with numerical results by means of computational fluid dynamics (CFD) from references and found in very good agreement. Finally, a selection of the airfoil with the best aerodynamic performance is done and proposed for further analysis including the blowing condition.
2016
This study investigated the performance of electric drive ducted lift-fan propeller in the airfoil during vertical take-off and landing (VTOL) condition. The experiment was conducted using subsonic wind tunnel in two configurations; with and without electric deducted fan (EDF), with three different speeds of lift-fan (50W, 100W and 175W). Three different types of Reynolds number (1.4x105, 2.8 x105, and 4.1 x105) were used to study the aerodynamics forces. The results indicated that airfoil fitted with 175W EDF with low Reynolds number produced significant lift to drag ratio. Thus, it is suitable for vertical take-off and landing (VTOL) purposes.
2021
: A wind tunnel test was conducted on a NACA 6409 airfoil in order to determine an angle of attack with -15 ̊, -10 ̊, -5 ̊, 0 ̊, 5 ̊, 10 ̊ and 15 ̊ . This Airfoil is designed in the CREO V.6 and printed in the 3D printer for the taken different experimental value. The coefficient of pressure was obtained from the upper surface and lower surface of the airfoil using multi tube pressure head manometer. Lift coefficient and Drag coefficient were measured at the 14.27 m/s velocity in the free stream test section at the various angle of attack. Experimental validation of the airfoil is carried out with the CFD analysis of the airfoil at different angle of attack, where experimental atmosphere of the test section created in the CFD analysis.
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