Unsettled Topics Concerning Flying Cars for Urban Air Mobility

2021 ◽  
Author(s):  
Yangjun Zhang ◽  
Keyword(s):  
Electric Propulsion ◽  
Innovation System ◽  
Development Trend ◽  
Urban Air ◽  
High Lift ◽  
History Of ◽  
New Type ◽  
Vehicle Technology ◽  
Drag Ratio ◽  
Lift To Drag Ratio

Flying cars—as a new type of vehicle for urban air mobility (UAM)—have become an important development trend for the transborder integration of automotive and aeronautical technologies and industries. This article introduces the 100-year history of flying cars, examines the current research status for UAM air buses and air taxis, and discusses the future development trend of intelligent transportation and air-to-land amphibious vehicles. Unsettled Topics Concerning Flying Cars for Urban Air Mobility identifies the major bottlenecks and impediments confronting the development of flying cars, such as high power density electric propulsion, high lift-to-drag ratio and lightweight body structures, and low-altitude intelligent flight. Furthermore, it proposes three phased goals and visions for the development of flying cars in China, suggesting the development of a flying vehicle technology innovation system that integrates automotive and aeronautic industries.

scholarly journals A Parametric Study of Trailing Edge Flap Implementation on Three Different Airfoils Through an Artificial Neuronal Network

Symmetry ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 828
Author(s):  
Igor Rodriguez-Eguia ◽  
Iñigo Errasti ◽  
Unai Fernandez-Gamiz ◽  
Jesús María Blanco ◽  
Ekaitz Zulueta ◽  
...  
Keyword(s):  
Aerodynamic Coefficients ◽  
Trailing Edge ◽  
High Lift ◽  
Trailing Edge Flaps ◽  
Artificial Neural Network Ann ◽  
Lift And Drag ◽  
Artificial Neuronal Network ◽  
Naca 0012 ◽  
Drag Ratio ◽  
Lift To Drag Ratio

Trailing edge flaps (TEFs) are high-lift devices that generate changes in the lift and drag coefficients of an airfoil. A large number of 2D simulations are performed in this study, in order to measure these changes in aerodynamic coefficients and to analyze them for a given Reynolds number. Three different airfoils, namely NACA 0012, NACA 64(3)-618, and S810, are studied in relation to three combinations of the following parameters: angle of attack, flap angle (deflection), and flaplength. Results are in concordance with the aerodynamic results expected when studying a TEF on an airfoil, showing the effect exerted by the three parameters on both aerodynamic coefficients lift and drag. Depending on whether the airfoil flap is deployed on either the pressure zone or the suction zone, the lift-to-drag ratio, CL/CD, will increase or decrease, respectively. Besides, the use of a larger flap length will increase the higher values and decrease the lower values of the CL/CD ratio. In addition, an artificial neural network (ANN) based prediction model for aerodynamic forces was built through the results obtained from the research.

Optimal Design of Wind Turbines Using BIAS, A Method of Multipliers Code

1988 ◽  
Author(s):  
B. D. Vick ◽  
W. Wrigglesworth ◽  
L. B. Scott ◽  
K. M. Ragsdell
Keyword(s):  
Optimal Design ◽  
Rough Surface ◽  
Wind Turbines ◽  
Lift Coefficient ◽  
Power Coefficient ◽  
Method Of Multipliers ◽  
High Lift ◽  
Small Wind Turbines ◽  
Drag Ratio ◽  
Lift To Drag Ratio

Abstract A method has been developed and is demonstrated which determines the chord and twist distribution for a wind turbine with maximum power coefficient. Only small wind turbines (less than 10 kilowatts) are considered in this study, but the method could be used for larger wind turbines. Glauert determined a method for estimating the chord and twist distribution that will maximize the power coefficient if there is no drag. However, the method proposed here determines the chord and twist distribution which will maximize the power coefficient with the effect of drag included. Including drag in the analysis does not significantly affect the Glauert chord and twist distribution for airfoils with a high lift coefficient at the maximum lift to drag ratio. However, if the airfoil has a fairly low lift coefficient at its maximum lift to drag ratio due to its shape or a rough surface then significant improvement can be obtained in power coefficient by altering the Glauert chord and twist distribution according to the method proposed herein.

Roughness Sensitivity Considerations for Thick Rotor Blade Airfoils

2003 ◽  
Vol 125 (4) ◽  
pp. 468-478 ◽  
Author(s):  
R. P. J. O. M. van Rooij ◽  
W. A. Timmer
Keyword(s):  
Turbine Blades ◽  
Leading Edge ◽  
Lower Surface ◽  
Vortex Generators ◽  
Wind Turbine Blades ◽  
High Lift ◽  
Edge Roughness ◽  
Proper Design ◽  
Drag Ratio ◽  
Lift To Drag Ratio

In modern wind turbine blades, airfoils of more than 25% thickness can be found at mid-span and inboard locations. At mid-span, aerodynamic requirements dominate, demanding a high lift-to-drag ratio, moderate to high lift and low roughness sensitivity. Towards the root, structural requirements become more important. In this paper, the performance for the airfoil series DU FFA, S8xx, AH, Risø and NACA are reviewed. For the 25% and 30% thick airfoils, the best performing airfoils can be recognized by a restricted upper-surface thickness and an S-shaped lower surface for aft-loading. Differences in performance of the DU 91-W2-250 (25%), S814 (24%) and Risø-A1-24 (24%) airfoils are small. For a 30% thickness, the DU 97-W-300 meets the requirements best. Reduction of roughness sensitivity can be achieved both by proper design and by application of vortex generators on the upper surface of the airfoil. Maximum lift and lift-to-drag ratio are, in general, enhanced for the rough configuration when vortex generators are used. At inboard locations, 2-D wind tunnel tests do not represent the performance characteristics well because the influence of rotation is not included. The RFOIL code is believed to be capable of approximating the rotational effect. Results from this code indicate that rotational effects dramatically reduce roughness sensitivity effects at inboard locations. In particular, the change in lift characteristics in the case of leading edge roughness for the 35% and 40% thick DU airfoils, DU 00-W-350 and DU 00-W-401, respectively, is remarkable. As a result of the strong reduction of roughness sensitivity, the design for inboard airfoils can primarily focus on high lift and structural demands.

420 Aerodynamic Characteristics and Flow Field of High Lift-to-drag Ratio Airfoils in Low Reynolds Number

2015 ◽  
Vol 2015.68 (0) ◽  
pp. 167-168 ◽  
Author(s):  
Takahiro MAKIZONO ◽  
Gaku SASAKI ◽  
Hiroshi OCHI ◽  
Takaaki MATSUMOTO ◽  
Koichi YONEMOTO
Keyword(s):  
Reynolds Number ◽  
Flow Field ◽  
Low Reynolds Number ◽  
Aerodynamic Characteristics ◽  
High Lift ◽  
Low Reynolds ◽  
Drag Ratio ◽  
Lift To Drag Ratio

Character Measurement of Flapping-Wing Mechanism

2011 ◽  
Vol 48-49 ◽  
pp. 300-303
Author(s):  
Yun Liu ◽  
Zhi Sheng Jing ◽  
Shan Chao Tu ◽  
Ming Hao Yu ◽  
Guo Wei Qin
Keyword(s):  
Lift Force ◽  
Aerodynamic Force ◽  
Development Trend ◽  
Flapping Wing ◽  
Generation Efficiency ◽  
High Lift ◽  
Effect Analysis ◽  
New Type ◽  
Force Mechanism ◽  
The Development Trend

The characteristics and the application prospect are analyzed. It is concluded that bionic flapping-wing flying has better lift fore generation efficiency, which is the development trend of aerial vehicles. By the scaling effect analysis on bionic flying mechanism, it is presented that bionic flying could be realized more easily when the sizes are decreased. In this article, the flying mechanism of inset and Aves was studied and the high lift force mechanism of flapping-winging was concluded. In order to make the flapping-flying easier, we design a new type flapping-flying mechanism. A set of flapping-wing move comparatively. It can provide lift force all the time. We test the lift force in the condition of different speed and different frequency. The lift effect is validated on a simple suspend flight device. An experimental platform to measure the aerodynamic force is devised and developed by ourselves. On this equipment, the aerodynamics force of the prototype is test. The result is that enhancing speed or frequency can improve lift force in evidence

scholarly journals Proposal of an Optimized Airfoil Geometry for Vertical-Axis Wind Turbine Applications

Proceedings ◽  
2018 ◽  
Vol 2 (23) ◽  
pp. 1464
Author(s):  
Andrés Meana-Fernández ◽  
Lorena Díaz-Artos ◽  
Jesús Manuel Fernández Oro ◽  
Sandra Velarde-Suárez
Keyword(s):  
Wind Turbine ◽  
Vertical Axis ◽  
Vertical Axis Wind Turbine ◽  
High Lift ◽  
Actual Solution ◽  
Stall Angle ◽  
User Friendly ◽  
Drag Ratio ◽  
Lift To Drag Ratio ◽  
High Angles Of Attack

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 the performance of the proposed airfoil shape (UO-17-LDA). This airfoil presents a high lift-to-drag ratio and a delayed stall angle with respect to the original FX-63-137 airfoil, making it suitable for vertical-axis wind turbine applications. The practicality of JavaFoil for the comparison of different airfoil geometries has been verified, as it is capable of obtaining results for a wide number of flow conditions in small computational times and with a user-friendly interface. Nevertheless, the results diverge from the actual solution for high angles of attack (beyond stall).

Numerical and Experiment Study on New Types of Magnus Blade

2014 ◽  
Vol 472 ◽  
pp. 271-275
Author(s):  
Ying Xue Yao ◽  
Xue Wen Wang ◽  
Jin Ming Wu
Keyword(s):  
Wind Turbine ◽  
Simple Structure ◽  
Low Cost ◽  
Fossil Energy ◽  
Low Wind Speed ◽  
2D Simulation ◽  
New Energy ◽  
New Type ◽  
Drag Ratio ◽  
Lift To Drag Ratio

Fossil energy is becoming less and less, as one of new energy, many countries pay more attention on wind energy. Magnus wind turbine has an advantage of simple structure, low cost. It can work well at a very low wind speed and the control system is very simple. As the cylinder blade of traditional Magnus wind turbine has a relatively low lift to drag ratio, This paper provide two new type blade of Magnus wind turbine and it can greatly improve lift to drag ratio of Magnus wind turbine. This paper will use CFD software Fluent, through 2D simulation, compare the lift to drag ratio of cylinder blades. At last, do experiments to compare the performance of these blades.

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