Numerical Study of Dynamic Ground Effect of a Carrier-Based UAV

2015 ◽  
Vol 733 ◽  
pp. 522-525
Author(s):  
Mu Qing Yang ◽  
Dong Li Ma
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Aerodynamic Force ◽  
Numerical Study ◽  
Ground Effect ◽  
Pitching Moment ◽  
Aerodynamic Forces ◽  
Sliding Mesh ◽  
The Stability

The paper uses computational fluid dynamics combined with sliding mesh and dynamic layering methods to study the dynamic ground effect of a UVA during the phase of takeoff. The research focused on longitude characteristics, such as lift, drag and pitching moment. Results showed that the aerodynamic force would vibrate acutely, which affected the stability of the UAV and the safety of takeoff. Pitching angle is the most important factor influencing the aerodynamic forces. Increase the pitching angle properly is benefit to the safety of takeoff operation.

scholarly journals Применение CFD для проектирования системы управления движением экраноплана

2020 ◽  
Author(s):  
A.V. Nebylov ◽  
S.A. Brodsky ◽  
A.I. Panferov ◽  
V.A. Nebylov
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Control System ◽  
Motion Control ◽  
Numerical Study ◽  
Ground Effect ◽  
Comsol Multiphysics ◽  
Motion Control System ◽  
Control Laws ◽  
Interactive Control

В статье рассматриваются возможности применения программного пакета Comsol Multiphysics на стадии предварительного проектирования системы автоматического управления движением экраноплана. Разработка новых методов синтеза алгоритмов управления движением в зоне действия экранного эффекта базируется на результатах численного исследования аэродинамики летательного аппарата и расчета аэродинамических сил и моментов с использованием модуля вычислительной гидродинамики CFD ( computational fluid dynamics , позднее переименованный в colorful fluid dynamics или разноцветная гидродинамика ), расширяющего возможности среды численного моделирования COMSOL Multiphysics. Мелкие и непринципиальные для интегральной аэродинамики элементы конструкции не учитывались. Конструкция создавалась непосредственно в графическом редакторе COMSOL с целью избежать непредсказуемых ошибок конвертации. Многосеточные методы были использованы для повышения точности и сокращения времени решения. Полученные модели и законы управления позволяют создать симулятор управляемого движения экраноплана с функциями симулятора полета. На основе симулятора планируется создание системы краткосрочного прогнозирующего интерактивного управления в ускоренное время. Аппаратная реализация этой системы как части автоматической системы управления движением включает в себя также систему отображения информации, подразумевающую допустимое сокращение сложности модели системы и законов управления.The article discusses the possibilities of using the Comsol Multiphysics software package at the stage of preliminary design of a motion control system for a promising big ekranoplane (WIG-craft). The development of new methods for synthesizing automatic motion control algorithms in the area of ground effect is based on the results of a numerical study of the vehicle aerodynamics and the calculation of aerodynamic forces and torques using the CFD ( computational fluid dynamics , later recalled in colorful fluid dynamics ) module, which expands the capabilities of the COMSOL Multiphysics numerical simulation environment. Small and unprincipled structural elements slightly influenced integral aerodynamics were not taken into account. The design was created directly in the COMSOL graphics editor in order to avoid unpredictable conversion errors. Multigrid methods have been used to reduce the solution time. The resulting model and the control laws allow to create a simulation of the controlled motion of airplane with flight simulator. Based on this simulator, it is planned to create a system of short-term predictive interactive control in accelerated time. The hardware implementation of this system as a part of an automatic motion control system also includes an information display system that implies an acceptable reduction in the complexity of the system model and control laws.

Cooling and Freezing of Cashew Apple Using Computational Fluid Dynamics

2020 ◽  
Vol 25 ◽  
pp. 114-132 ◽  
Author(s):  
V.A. Agra Brandão ◽  
R. Araújo de Queiroz ◽  
R. Lima Dantas ◽  
G. Santos de Lima ◽  
N. Lima Tresena ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Nutritional Value ◽  
Fruits And Vegetables ◽  
Numerical Study ◽  
Freezing Process ◽  
Ansys Cfx ◽  
Cashew Apple ◽  
Freezing Period ◽  
Kinetics Of

Freezing is one the most efficient methods for conservation, especially, fruits and vegetables. Cashew is a fruit with high nutritional value and great economic importance in the Northeast region of Brazil, however, due to high moisture content, it is highly perishable. The numerical study of the freezing process is of great importance for the optimization of the process. In this sense, the objective of this work was to study the cooling and freezing processes of cashew apple using computational fluid dynamics technique. Experiments of cooling and freezing of the fruit, with the aid of a refrigerator,data acquisition system and thermocouples, and simulation using Ansys CFX® software for obtain the cooling and freezing kinetics of the product were realized. Results of the cooling and freezing kinetics of the cashew apple and temperature distribution inside the cashew apple are presented, compared and analyzed. The model was able to predict temperaturetransient behavior with good accuracy, except in the post-freezing period.

Numerical study of the biomass pyrolysis process in a spouted bed reactor through computational fluid dynamics

Energy ◽  
2021 ◽  
Vol 214 ◽  
pp. 118839
Author(s):  
Shiliang Yang ◽  
Ruihan Dong ◽  
Yanxiang Du ◽  
Shuai Wang ◽  
Hua Wang
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Numerical Study ◽  
Pyrolysis Process ◽  
Biomass Pyrolysis ◽  
Spouted Bed

Wind Tunnel Testing and Computational Fluid Dynamics Analysis of a Wing-in-Ground Effect Vehicle

2007 ◽  
Author(s):  
Boonseng Soh ◽  
Andrew Low ◽  
Cees Bil ◽  
Brendon Bobbermien
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Wind Tunnel ◽  
Ground Effect ◽  
Wind Tunnel Testing ◽  
Cfd Modelling ◽  
Aerodynamic Analysis ◽  
Computational Fluid Dynamics Analysis ◽  
Wing In Ground Effect ◽  
Tunnel Testing

The Wing-in-Ground Effect Concept Technology Demonstrator (WIGE CTD) project is a joint venture between Advanced Aerosystem Technologies Pty Ltd and RMIT University, aiming to design, validate and build a prototype recreational vehicle to fly two passengers over a distance of 500km at approximately 120km/h. The WIGE vehicle will fly very close to the surface, usually water, taking advantage of ground effect to transport passengers with a greater lift/drag ratio, and thus greater fuel-efficiency than conventional aircraft. Following preliminary design, an aerodynamic analysis of the vehicle was performed using wind tunnel testing and Computational Fluid Dynamics (CFD). This paper describes the methods used for wind tunnel testing and CFD modelling of the WIGE CTD design. Results obtained using the two approaches are compared with the aim of validating the CFD model and the techniques used in both wind tunnel and CFD modelling for use in future analyses. In addition to the aerodynamic analysis, a basic CFD prediction of the maximum hydrodynamic drag experienced during take off was attempted using a simple model of the WIGE vehicle hull. This result is required in order to ensure that the aquatic take off required by WIGE vehicles was possible for the design. Concurrently, the feasibility of using a general-purpose CFD solver like Fluent to analyse hull performance was also evaluated through this aspect of the investigation.

Experimental and Numerical Study of Ascending Aorta Hemodynamics Through 3D Particle Tracking Velocimetry and Computational Fluid Dynamics

2013 ◽  
Author(s):  
Utku Gülan ◽  
Diego Gallo ◽  
Raffaele Ponzini ◽  
Beat Lüthi ◽  
Markus Holzner ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Particle Tracking ◽  
Particle Tracking Velocimetry ◽  
Numerical Study ◽  
Imaging Techniques ◽  
Ascending Aorta ◽  
Human Aorta ◽  
Wide Range

The complex hemodynamics observed in the human aorta make this district a site of election for an in depth investigation of the relationship between fluid structures, transport and pathophysiology. In recent years, the coupling of imaging techniques and computational fluid dynamics (CFD) has been applied to study aortic hemodynamics, because of the possibility to obtain highly resolved blood flow patterns in more and more realistic and fully personalized flow simulations [1]. However, the combination of imaging techniques and computational methods requires some assumptions that might influence the predicted hemodynamic scenario. Thus, computational modeling requires experimental cross-validation. Recently, 4D phase contrast MRI (PCMRI) has been applied in vivo and in vitro to access the velocity field in aorta [2] and to validate numerical results [3]. However, PCMRI usually requires long acquisition times and suffers from low spatial and temporal resolution and a low signal-to-noise ratio. Anemometric techniques have been also applied for in vitro characterization of the fluid dynamics in aortic phantoms. Among them, 3D Particle Tracking Velocimetry (PTV), an optical technique based on imaging of flow tracers successfully used to obtain Lagrangian velocity fields in a wide range of complex and turbulent flows [4], has been very recently applied to characterize fluid structures in the ascending aorta [5].

Optimal Design of a New Type of Savonius Rotor Using Simulation Analysis

2012 ◽  
Vol 499 ◽  
pp. 120-125 ◽  
Author(s):  
Zhi Peng Tang ◽  
Ying Xue Yao ◽  
Liang Zhou ◽  
Q. Yao
Keyword(s):  
Fluid Dynamics ◽  
Numerical Simulation ◽  
Computational Fluid Dynamics ◽  
Optimal Design ◽  
Simulation Analysis ◽  
Structural Parameters ◽  
Sliding Mesh ◽  
Savonius Rotor ◽  
Mesh Method ◽  
New Type

In order to enhance the efficiency of the Savonius rotor, this paper designs a new type of Savonius rotor with a rectifier. By using Computational Fluid Dynamics software to simulate and optimize the various parameters which affect the efficiency of the rotor. The sliding mesh method is applied here. The Cp-λ curves of wind turbine with different structural parameters are obtained after numerical simulation of flow field. On this basis, this paper gets the optimal structural parameters. And the results indicated that this new type of Savonius rotor has great improvement of efficiency compared with the traditional Savonius-type rotor.

Vehicles Aerodynamics while Crossing each other on Road Based on Computational Fluid Dynamics

2010 ◽  
Vol 29-32 ◽  
pp. 1344-1349 ◽  
Author(s):  
Zhe Zhang ◽  
Ying Chao Zhang ◽  
Jie Li
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Numerical Simulations ◽  
Aerodynamic Force ◽  
The Other ◽  
Moving Mesh ◽  
Aerodynamic Coefficients ◽  
Paper Report ◽  
Vehicle Aerodynamics ◽  
Simulation Results

When vehicles run on road, they will be overtaken, cross by other vehicles or be impacted by crosswind. The other events of overtaking and in crosswind were investigated more deeply. A few of paper report the state of the research on this problem. Until now there are no any wind tunnel and road tests to study on road vehicle aerodynamics while crossing each other. Some numerical simulations were carried out by adopting technology of sliding interface and moving mesh. The method of numerical simulations was narrated in detail. The transient process of vehicles crossing each other was realized. Then the trends of aerodynamic coefficients changing were obtained from the flow field of simulation results. The quantificational changing of vehicles aerodynamic coefficients was obtained when they cross each other. The vehicles are sedan and coach. The simulation results indicated that the all aerodynamic coefficients of two vehicles changed large. The aerodynamic force was important to the vehicles’ handling stability when they cross each other.

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