CREATION OF AN EXPERIMENTAL CONTROL BODY (ELEVON) IN THE «FLYING WING» AERODYNAMIC SCHEME

2021 ◽  
Vol 2 (28) ◽  
pp. 26-32
Author(s):  
D. V. Elenin ◽  
Keyword(s):  
Wind Tunnel ◽  
Flow Velocity ◽  
Key Words ◽  
Incoming Flow ◽  
Aerodynamic Design ◽  
Experimental Control ◽  
Flow Environment ◽  
Control Body

The article discusses the possibility of creating two schemes of an experimental control body in flight for a UAV of the "Flying Wing" scheme. The concept of creating a real prototype for an experiment in the Solidworks Flow environment and in a wind tunnel with a low incoming flow velocity is presented. Key words: wing, aerodynamic design, UAV, flying wing.

Numerical study of the aerodynamic and power characteristics of the cycloidal rotor, under incoming flow

2019 ◽  
pp. 25-34
Author(s):  
Александр Анатольевич Дектерев ◽  
Артем Александрович Дектерев ◽  
Юрий Николаевич Горюнов
Keyword(s):  
Flow Velocity ◽  
Numerical Study ◽  
Lift Coefficient ◽  
Simulation Method ◽  
Aerodynamic Characteristics ◽  
Incoming Flow ◽  
Ansys Fluent ◽  
Energy Characteristics ◽  
Power Characteristics ◽  
Calculation Results

Исследование направлено на разработку и апробацию методики численного моделирования аэродинамических и энергетических характеристик циклоидального ротора. За основу взята конфигурация ротора IAT21 L3. Для нее с использованием CFD-пакета ANSYS Fluent построена математическая модель и выполнен расчет. Проанализировано влияние скорости набегающего потока воздуха на движущийся ротор. Математическая модель и полученные результаты исследования могут быть использованы при создании летательных аппаратов с движителями роторного типа. This article addresses the study of the aerodynamic and energy characteristics of a cycloidal rotor subject to the influence of the incoming flow. Cycloidal rotor is one of the perspective devices that provide movement of aircrafts. Despite the fact that the concept of a cycloidal rotor arose in the early twentieth century, the model of a full-scale aircraft has not been yet realized. Foreign scientists have developed models of aircraft ranging in weight from 0.06 to 100 kg. The method of numerical calculation of the cycloidal rotor from the article [1] is considered and realized in this study. The purpose of study was the development and testing of a numerical simulation method for the cycloidal rotor and study aerodynamic and energy characteristics of the rotor in the hovering mode and under the influence of the oncoming flow. The aerodynamic and energy characteristics of the cycloidal rotor, rotating at a speed of 1000 rpm with incoming flow on it with velocities of 20-80 km/h, were calculated. The calculation results showed a directly proportional increase of thrust with an increase of the incoming on the rotor flow velocity, but the power consumed by the rotor was also increased. Increase of the incoming flow velocity leads to the proportional increasing of the lift coefficient and the coefficient of drag. Up to a speed of 80 km/h, an increase in thrust and power is observed; at higher speeds, there is a predominance of nonstationary effects and difficulties in estimating the aerodynamic characteristics of the rotor. In the future, it is planned to consider the 3D formulation of the problem combined with possibility of the flow coming from other sides.

scholarly journals Kandungan Logam Berat Besi (Fe) Pada Air, Sedimen, Dan Kerang Hijau (Perna viridis) Di Perairan Tanjung Emas Semarang

2015 ◽  
Vol 18 (1) ◽  
Author(s):  
Endang Supriyantini ◽  
Hadi Endrawati
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Flow Velocity ◽  
Atomic Absorption ◽  
Key Words ◽  
Atomic Absorption Spectrophotometry ◽  
Pollution Level ◽  
Perna Viridis ◽  
Absorption Spectrophotometry ◽  
Living Organisms

Logam berat Fe merupakan logam berat essensial yang keberadaannya dalam jumlah tertentu sangat dibutuhkan oleh organisme hidup, namun dalam jumlah yang berlebih dapat menimbulkan efek racun.Penelitian ini bertujuan untuk menganalisis kandungan dan tingkat pencemaran logam berat Fe pada air, sedimen, dan kerang hijau (Perna viridis) di perairan Tanjung Emas Semarang. Penelitian ini dilaksanakan pada tanggal 7 November dan 7 Desember 2013 dengan metode penelitian deskriptif. Logam berat Fe dalam sampel air, sedimen dan kerang hijau dianalisis di Laboratorium Balai Besar Teknologi Pencegahan Pencemaran Industri (BTPPI) Semarang dengan menggunakan metode AAS (AtomicAbsorption Spectrophotometry). Hasil penelitian menunjukkan bahwa perairan Tanjung Emas masih dalam taraf terkontaminasi logam Fe. Sedangkan pada sedimen dan pada kerang hijau (Perna viridis) sudah terindikasi tercemar logam Fe.Meskipun demikian variasi faktor lingkungan seperti suhu, salinitas, pH, kecepatan arus dan jenis sedimen juga memberikan kontribusi yang cukup penting terhadap kandungan logam Fe.Kata Kunci: logam Fe, Air, Sedimen, Perna viridis, metode AAS Heavy metalsiron(Fe) is anessentialheavy metalswhose presencein a certain amountis neededby living organisms, but inexcessiveamountscan causetoxic effects.The aims of the research is to analyze the heavy metals coccentration and the pollution level of Fe in water, sediment, and green mussels (Perna viridis) at Tanjung Emas Semarang. This research was conducted from 7 November and 7 December 2013 using the Atomic Absorption Spectrophotometry (AAS) and research methodswithdescriptive. The results showed that the waters of the Tanjung Emas is still in the stage of heavy metals contaminated iron (Fe). Sediment and green mussels (Perna viridis)already indicated heavy metal contaminatediron. However, variations inenvironmental factorssuch astemperature, salinity, pH, flow velocity an dsediment types also providean important contributionto heavy metal contentof iron(Fe).Key Words: Fe, water, sediment, Perna viridis, metode AAS

Local Heat/Mass Transfer Characteristics on a Rotating Blade With Flat Tip in a Low-Speed Annular Cascade—Part II: Tip and Shroud

2005 ◽  
Vol 128 (1) ◽  
pp. 110-119 ◽  
Author(s):  
Dong-Ho Rhee ◽  
Hyung Hee Cho
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Flow Velocity ◽  
Rotational Speed ◽  
Heat Mass Transfer ◽  
Local Heat ◽  
Incoming Flow ◽  
Transfer Coefficients ◽  
Low Speed ◽  
Annular Cascade

The local heat/mass transfer characteristics on the tip and shroud were investigated using a low speed rotating turbine annular cascade. Time-averaged mass transfer coefficients on the tip and shroud were measured using a naphthalene sublimation technique. A low speed wind tunnel with a single stage turbine annular cascade was used. The turbine stage is composed of sixteen guide plates and blades. The chord length of blade is 150 mm and the mean tip clearance is about 2.5% of the blade chord. The tested Reynolds number based on inlet flow velocity and blade chord is 1.5×105 and the rotational speed of the blade is 255.8 rpm at design condition. The results were compared with the results for a stationary blade and the effects of incidence angle of incoming flow were examined for incidence angles ranging from −15 to +7deg. The off-design test conditions are obtained by changing the rotational speed with a fixed incoming flow velocity. Flow reattachment on the tip near the pressure side edge dominates the heat transfer on the tip surface. Consequently, the heat/mass transfer coefficients on the blade tip are about 1.7 times as high as those on the blade surface and the shroud. However, the heat transfer on the tip is about 10% lower than that for the stationary case due to reduced leakage flow with the relative motion. The peak regions due to the flow reattachment are reduced and shifted toward the trailing edge and additional peaks are formed near the leading edge region with decreasing incidence angles. But, quite uniform and high values are observed on the tip with positive incidence angles. The time-averaged heat/mass transfer on the shroud surface has a level similar to that of the stationary cases.

Development of a Surface Flow Sensor for Measuring Turbulent Drag Force

2019 ◽  
Author(s):  
Il Doh ◽  
Il-Bum Kwon ◽  
Jiho Chang ◽  
Sejong Chun
Keyword(s):  
Wind Tunnel ◽  
Flow Velocity ◽  
Drag Force ◽  
Mass Flow ◽  
Surface Flow ◽  
Flow Sensor ◽  
Constant Current ◽  
Thermal Mass ◽  
Turbulent Drag ◽  
Mass Flow Sensor

Abstract A surface flow sensor is needed if turbulent drag force is to be measured over a vehicle, such as a car, a ship, and an airplane. In case of automobile industry, there are no automobile manufacturers which measure surface flow velocity over a car for wind tunnel testing. Instead, they rely on particle image velocimetry (PIV), pressure sensitive paint (PSP), laser Doppler anemometry (LDA), pitot tubes, and tufts to get information regarding the turbulent drag force. Surface flow sensors have not devised yet. This study aims at developing a surface flow sensor for measuring turbulent drag force over a rigid body in a wind tunnel. Two sensing schemes were designed for the fiber-optic distributed sensor and the thermal mass flow sensor. These concepts are introduced in this paper. As the first attempt, a thermal mass flow sensor has been fabricated. It was flush-mounted on the surface of a test section in the wind tunnel to measure the surface flow velocity. The thermal mass flow sensor was operated by either constant current or constant resistance modes. Resistance ratio was changed as the electric current was increased by the constant current mode, while power ratio was saturated as the resistance was increased by the constant resistance mode. Either the resistance ratio or the power ratio was changed with the flow velocity measured by a Pitot tube, located at the center of test section.

Unsteady Simulations for an Advanced-Louver Cooling Scheme

2008 ◽  
Author(s):  
Chad X.-Z. Zhang ◽  
Sung In Kim ◽  
Ibrahim G. Hassan
Keyword(s):  
Reynolds Number ◽  
Wind Tunnel ◽  
Flat Plate ◽  
Flow Velocity ◽  
Detached Eddy Simulation ◽  
Computer Cluster ◽  
Vortical Structures ◽  
Eddy Simulation ◽  
Mainstream Flow ◽  
Adiabatic Effectiveness

The performance of a louver cooling scheme on a flat plate was analyzed using Detached Eddy Simulation. It was assumed that the louver cooling scheme was tested in a wind tunnel with the mainstream flow velocity of 20 m/s, equivalent to a Reynolds number of 16200 based on the jet diameter. Turbulence closure was achieved by a Realizable k-ε based DES turbulence model. Solutions of two blowing ratios of 0.5 and 1 were successfully obtained by running parallel on 16 nodes on a computer cluster. The instantaneous flow fields were found to be highly unsteady and oscillatory in nature. It is shown that the fluctuations in the adiabatic effectiveness are mainly caused by the spanwise fluctuation of the coolant jet and the unsteady vortical structures created by the interaction of the jet and the mainstream.

scholarly journals Aerodynamic Design of a Small-Scale Model of a Vertical Axis Wind Turbine

Proceedings ◽  
2018 ◽  
Vol 2 (23) ◽  
pp. 1465 ◽  
Author(s):  
Andrés Meana-Fernández ◽  
Jesús Manuel Fernández Oro ◽  
Katia María Argüelles Díaz ◽  
Mónica Galdo-Vega ◽  
Sandra Velarde-Suárez
Keyword(s):  
Wind Tunnel ◽  
Wind Turbine ◽  
Vertical Axis ◽  
Scale Model ◽  
Small Scale ◽  
Wind Tunnel Testing ◽  
Aerodynamic Design ◽  
Vertical Axis Wind Turbine ◽  
Small Scale Model ◽  
Tunnel Testing

Wind tunnel testing of small-scale models is one of the most useful techniques to predict the performance of real-scale applications. In this work, the aerodynamic design and the construction of a small-scale model of a straight-bladed vertical axis wind turbine for wind tunnel testing has been performed. Using a double multiple streamtube model (DMST), different solidity values for the turbine and different airfoil geometries were compared to select the final design. Once an optimal design was selected, a numerical simulation using Computational Fluid Dynamics (CFD) was performed in order to obtain a more precise description of the flow field as well as the performance of the model. Future work will comprise the characterization of the model and the comparison of the experimental and numerical results.

Wind Tunnel Test of Honeycomb in Improving Flow Quality

2013 ◽  
Vol 774-776 ◽  
pp. 275-278
Author(s):  
Chun Guang Li ◽  
Yang Liu ◽  
John.C.K. Cheung
Keyword(s):  
Wind Tunnel ◽  
Cell Size ◽  
Turbulence Intensity ◽  
Wind Tunnel Test ◽  
Open Loop ◽  
Incoming Flow ◽  
Flow Quality ◽  
The Mean ◽  
Square Cells ◽  
Change Tendency

The function of honeycomb with different length and width in improving flow quality were studied in the course of building a new small section open loop wind tunnel. Instantaneous velocities of turbulent flow in the tunnel were measured by cobra probe. The focus of this study was put on the effect of the honeycomb in attenuating the total turbulence intensity including the free-turbulence carried by the incoming flow and the turbulence generated by the square cells themselves. The change tendency of the mean wind velocity and the total turbulence characteristics in the decay area have been studied by varying the length to cell size ratio L/D, and ratio of distance between the square cells and the measuring position to cell size X/D.

Aerodynamic Performances and Flow Fields of Pareto Optimal Solutions in an Aerodynamic Design of a Wind-Lens Turbine

2015 ◽  
Author(s):  
Nobuhito Oka ◽  
Masato Furukawa ◽  
Kazutoyo Yamada ◽  
Akihiro Oka ◽  
Yasushi Kurokawa
Keyword(s):  
Optimal Design ◽  
Wind Tunnel ◽  
Design Method ◽  
Flow Fields ◽  
Pareto Optimal ◽  
Pareto Optimal Solutions ◽  
Optimal Solutions ◽  
Aerodynamic Design ◽  
Aerodynamic Performances ◽  
Optimal Design Method

The new type of shrouded wind turbine called “wind-lens turbine” has been developed. The wind-lens turbine has a brimmed diffuser called “wind-lens”, by which the wind concentration on the turbine blade and the significant enhancement of the turbine output can be achieved. A simultaneous optimization method for the aerodynamic design of rotor blade and wind-lens has been developed. The present optimal design method is based on a genetic algorithm (GA) which enables multi objective aerodynamic optimization. In the present study, aerodynamic performances and flow fields of the Pareto optimal solutions of wind-lens turbines designed by the present optimal design method have been investigated by wind-tunnel tests and three-dimensional Reynolds averaged Navier-Stokes (RANS) analyses. Output power coefficients obtained from the wind-tunnel tests in the optimal wind-lens turbine exceeded the Betz limit, which is the performance limitation for bare wind turbines. The numerical results and the experimental results show that the suppression of flow separations in the diffuser is important to achieve significant improvement in aerodynamic performances. As a result, it is found that the aerodynamic performance of wind-lens turbine is significantly affected by the interrelationship between the internal and external flow fields around the wind-lens.

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