Download or read book Numerical Simulation of DBD Plasma Actuators for Flow Control written by Huw Borradaile and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dielectric Barrier Discharge Microplasma Actuator for Flow Control written by Kazuo Shimizu and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Dielectric barrier discharge (DBD) plasma actuators are a technology which could replace conventional actuators due to their simple construction, lack of moving parts, and fast response. This type of actuator modifies the airflow due to electrohydrodynamic (EHD) force. The EHD phenomenon occurs due to the momentum transfer from charged species accelerated by an electric field to neutral molecules by collision. This chapter presents a study carried out to investigate experimentally and by numerical simulations a micro-scale plasma actuator. A microplasma requires a low discharge voltage to generate about 1 kV at atmospheric pressure. A multi-electrode microplasma actuator was used which allowed the electrodes to be energized at different potentials or waveforms, thus changing the direction of the flow. The modification of the flow at various time intervals was tracked by a high-speed camera. The numerical simulation was carried out using the Suzen-Huang model and the Navier-Stokes equations.
Download or read book A Direct Numerical Simulation of Dielectric Barrier Discharge DBD Plasma Actuators for Turbulent Skin friction Control written by Dana Elam and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flow Control Techniques and Applications written by Jinjun Wang and published by Cambridge University Press. This book was released on 2019 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: Master the theory, applications and control mechanisms of flow control techniques.
Download or read book Modeling of Dielectric Barrier Discharge Plasma Actuators for Flow Control Simulations written by Denis Palmeiro and published by . This book was released on 2011 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Single-dielectric-barrier-discharge (SDBD) plasma actuators have shown much promise as an actuator for active flow control. Proper design and optimization of plasma actuators requires a model capable of accurately predicting the induced flow for a range of geometrical and excitation parameters. A number of models have been proposed in the literature, but have primarily been developed in isolation on independent geometries, frequencies and voltages. This study presents a comparison of four popular plasma actuator models over a range of actuation parameters for three different actuator geometries typical of actuators used in the literature. The results show that the hybrid model of Lemire & Vo (2011) is the only model capable of predicting the appropriate trends of the induced velocity for different geometries. Additionally, several modifications of this model have been integrated into a new proposed model for the plasma actuator, introducing a number of improvements.
Download or read book Dbd Plasma Actuators for Flow Control in Air Vehicles and Jet Engines written by Nasa Technical Reports Server (Ntrs) and published by BiblioGov. This book was released on 2013-06 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NASA Technical Reports Servcr (NTRS) houses half a million publications that are a valuable means of information to researchers, teachers, students, and the general public. These documents are all aerospace related with much scientific and technical information created or funded by NASA. Some types of documents include conference papers, research reports, meeting papers, journal articles and more. This is one of those documents.
Download or read book Numerical Modeling of Microwave Plasma Actuators for Aerodynamic Flow Control written by Emanuele Arcese and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent decades, microwave discharge plasmas have attracted increasing attention of aerospace scientific community to the subject of aerodynamic flow control because of their capability of sub- stantially modifying the properties of the flow around bodies by effective energy deposition. The design and optimization of these plasma actuators as flow control technique require a compre- hensive understanding of the complex physics involved that the sole experiments are incapable to provide.In this context, we have interest in the numerical modeling of the mutual interaction of elec- tromagnetic waves with plasma and gas in order to better understand the nature of microwave discharges and their applicability. A challenging problem arises when modeling such phenomena because of the coupling of different physics and therefore the multiplicity of spatial and tempo- ral scales involved. A solution is provided by this thesis work which addresses both physics and applied mathematics questions related to microwave plasma modeling.The first part of this doctorate deals with validity matters of the physical model of microwave breakdown based on the local effective field concept. Because of large plasma density gradients, the local effective field approximation is questionable and thus a second-order plasma fluid model is developed, where the latter approximation is replaced by the local mean energy approximation. This modeling approach enables to take into account the non-locality in space of the electron energy balance that provides a more accurate description of the energy deposition by microwave plasma leading to the shock waves formation into the gas. A dimensionless analysis of the plasma fluid system is performed in order to theoretically characterize the non-locality of the introduced electron energy equation as function of the reduced electric field and wave frequency. It also discusses other approximations related to the choice and method of calculation of electron transport coefficients.Concerning the mathematical aspects, the thesis work focuses on the design and the analysis of a multiscale method for numerically solving the problem of electromagnetic wave propagation in microwave plasma. The system of interest consists of time-dependent Maxwell's equations coupled with a momentum transfer equation for electrons. The developed approach consists of a Schwartz type domain decomposition method based on a variational formulation of the standard Yee's scheme and using two levels of nested Cartesian grids. A local patch of finite elements is used to calculate in an iterative manner the solution in the plasma region where a better precision is required. The proposed technique enables a conservative local and dynamic refinement of the spatial mesh. The convergence behavior of the iterative resolution algorithm both in an explicit and implicit time-stepping formulation is then analyzed.In the last part of the doctorate, a series of numerical simulations of microwave breakdown and the filamentary plasma array formation in air are performed. They allow to study in detail the consequences of the different types of physical approximations adopted in the plasma fluid model. Then, these numerical experiments demonstrate the accuracy and the computational efficiency of the proposed patch correction method for the problem of interest. Lastly, a numerically investigation of the effects of gas heating on the formation and sustaining of the filamentary plasma array in atmospheric-pressure air is carried out. For doing this, the developed microwave-plasma model is coupled with unsteady Navier-Stokes equations for compressible flows. The simulations provide interesting features of the plasma array dynamics during the process of gas heating, in close agreement with experimental data.
Download or read book Shock Wave Boundary Layer Interactions written by Holger Babinsky and published by Cambridge University Press. This book was released on 2011-09-12 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shock wave-boundary-layer interaction (SBLI) is a fundamental phenomenon in gas dynamics that is observed in many practical situations, ranging from transonic aircraft wings to hypersonic vehicles and engines. SBLIs have the potential to pose serious problems in a flowfield; hence they often prove to be a critical - or even design limiting - issue for many aerospace applications. This is the first book devoted solely to a comprehensive, state-of-the-art explanation of this phenomenon. It includes a description of the basic fluid mechanics of SBLIs plus contributions from leading international experts who share their insight into their physics and the impact they have in practical flow situations. This book is for practitioners and graduate students in aerodynamics who wish to familiarize themselves with all aspects of SBLI flows. It is a valuable resource for specialists because it compiles experimental, computational and theoretical knowledge in one place.
Download or read book Numerical Modeling of Microscale Plasma Actuators written by Chin-Cheng Wang and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary weakness of DBD actuators is the relatively small actuation effect as characterized by the induced flow velocity. To improve upon this weakness for high speed flow control, the microscale discharge may be a remedy for increasing electric force.
Download or read book Numerical Simulations of Single Dielectric Barrier Discharge Plasma Actuators written by Kendal David Dennis and published by . This book was released on 2008 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book DBD Plasma Actuators for Flow Control in Air Vehicles and Jet Engines written by David E. Ashpis and published by . This book was released on 2011 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dielectric Barrier Discharge Plasma Actuator for Flow Control written by Dmitry F. Opaits and published by . This book was released on 2010 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optimisation of Dielectric Barrier Discharge Plasma Actuators and Their Application to Fluid Dynamics written by Rasool Erfani and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The standard dielectric barrier discharge (DBD) plasma actuator, in which an asymmetric arrangement of electrodes leads to momentum coupling into the surrounding air, has already demonstrated its capability for flow control. The effect of some parameters such as dielectric thickness, dielectric temperature, voltage amplitude, driving frequency, different configurations and arrangements on actuator performance are examined. The new configuration of DBD which uses multiple encapsulated electrodes (MEE) has been shown to produce a superior and more desirable performance over the standard actuator design. As the number of encapsulated electrodes increases and other variables such as the driving frequency and voltage amplitude are considered, finding the optimum actuator configuration for increasing the induced velocity becomes a challenge. The surrogate modelling optimisation provides a cheap and yet efficient method for systematically investigating the effect of different parameters on the performance of the plasma actuator. The effect of the optimum actuator configuration on the aerodynamic performance of an aerofoil under leading edge separation and wake interaction conditions is examined. The plasma actuator is placed at the leadingedge of a symmetric NACA 0015 aerofoil which corresponds to the location of the leading edge slat. The aerofoil is operated at a chord Reynolds number of 0.2×10 6. Surface pressure measurements along with the mean velocity profile of the wake using pitot measurements are used to determine the lift and drag coefficients, respectively. Particle image velocimetry (PIV) is also utilised to visualise and quantify the induced flow field. In comparison with reported literature on the standard DBD configuration, the MEE setup employed here is shown to provide a better means of flow control for the control of aerofoil separation. The characteristicsof a DBD plasma actuator when exposed to an unsteady flow generated by a shock tube is also investigated. This type of flow, which is often used in different studies, contains a range of flow regimes from sudden pressure and density changes to relatively uniform high-speed flow regions. A small circular shock tube is employed along with the schlieren photography technique to visualise the flow. The voltage and current traces of the plasma actuator are monitored throughout, and using the well established shock tube theory the change in the actuator characteristics are related to the physical processes which occur inside the shocktube. The results show that not only is the shear layer outside of the shock tube affected by the plasma but the passage of the shock front and high-speed flow behind it also greatly influences the properties of the plasma.
Download or read book Physical and Numerical Modeling of Dielectric Barrier Discharge Actuators for Flow Control Problems written by Rocco Arpa and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Model of Channel Dielectric Barrier Discharge Actuator written by Karthik Naganathan and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma actuators are active flow control devices used for vortex generation, momentum addition, and boundary layer attachment. The advantages of plasma actuators are that they are lightweight, quick to respond, and lack moving parts. Channel Dielectric Barrier Discharge actuators are a type of dielectric barrier discharge actuators in which the exposed electrode is placed in the bulk fluid to reduce viscosity effects. There are very few models that can predict the plasma forcing with good accuracy. These models however do not account for the geometric parameters such as the width of the electrode. This thesis discusses two numerical models, one built from a surface DBD model and one built from electrostatic modeling. The modified surface DBD model predicts exit velocity profiles similar to the experimental results. But it fails to account for some geometric parameters. The electrostatic model successfully captures the potential distribution asymmetry. The forcing function obtained by curve fitting the force distribution was adjusted to give reasonable velocity distribution when implemented as a source term in the CFD solver. The adjusted ES model predicted velocity contours and Reynolds number variation with good accuracy.
Download or read book Dielectric Barrier Discharge Plasma Actuator for Flow Control Final Report written by Dmitry Florievich Opaits and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation of Flow Around Cylinder Actuated by DBD Plasma written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The electric-static body force model is obtained by solving Maxwell's electromagnetic equations. Based on the electro-static model, numerical modeling of flow around a cylinder with a dielectric barrier discharge (DBD) plasma effect is also presented. The flow streamlines between the numerical simulation and the particle image velocimetry (PIV) experiment are consistent. According to the numerical simulation, DBD plasma can reduce the drag coefficient and change the vortex shedding frequencies of flow around the cylinder.
