Investigating a Process of Accelerating Macroscopic Objects in an Eddy-Current Inductance Coil Magnetic Field (original) (raw)

Analysis of capacitively driven electromagnetic coil guns

The XIX International Conference on Electrical Machines - ICEM 2010, 2010

In this paper, the performance analysis of two stages linear induction launcher (LIL) is presented. It is carried out based on current filament model (CFM) taking their transient behavior into account. A computer simulation based on the developed model, is down for predicting the electromechanical characteristics of the launcher (Current, velocity force, etc.). The section to section transitions which have significant effects on the launcher performance are also studied. Some simulation results are presented and discussed.

Inductance calculation of a coil gun that launches a thin plate edge-on

Digest of Technical Papers. 11th IEEE International Pulsed Power Conference (Cat. No.97CH36127)

A coil gun is a type of induction launcher that induces an eddy current in a metal projectile by a time varying magnetic induction produced by a launch coil. The interaction between the magnetic induction of the coil and the eddy currents can launch the plate with the velocity vector in the plane of the plate, i.e. edge-on 1 A previous published calculation of the eddy current in thin plates 2 includes the conductivity of the plate and the time variation of the applied magnetic field, which complicates the problem. Although these features are necessary for a general treatment of the subject, they complicate the problem and may not be necessary for applications where the skin depth is small compared to the length or width of the plate. For simplification, it has been assumed that the rectangular plate has an infinite conductivity, the plate has zero thickness, the applied magnetic induction is static, and the streamline function for the eddy currents can be expressed as a polynomial with adjustable coefficients. The curl of the stream line function yields the current density distribution. Under these assumptions, the integrals that result from the application of the Biot-Savart law are in principle analytic for any order of the polynomial, but their functional forms are very complicated. Their values, however, can be found by using recursion relations 3. After the evaluation of these integrals, the coefficients of the polynomial are adjusted so that the boundary conditions for the magnetic induction are satisfied on the plate's surface. This streamline function is then used to find the mutual inductance between the launch coil and plate for the given position. This procedure is repeated for other plate positions. With these results, it is possible to design the power supply for the coil gun and to predict the plate's velocity.

Optimization of parameters acting on a projectile velocity within a four stage induction coil-gun

Measurement, 2010

In this work, a four stage induction coil-gun has been designed and the parameters acting on the bullet velocity has been investigated. The mutual inductance variation depending on the bullet coil position, determination of firing point exposed to the maximum force with respect to the length, and appropriate material selection for the bullet coil have been analyzed. Optimum solutions for these parameters have been presented.

Performance of an induction coil gun

1993

Performanceof an electromagnetic induction launcheris consideredfor three types of armatures. These are: Solid, l-element wound and 16-element wound aluminum armatures. The one element wound armaturehas uniform current density throughout. Because of the radial distribution of the current density, the wound armature can withstandfield reversal(workingagainstembedded flux inthe armature)and still maintain low temperature. Slingshot simulations were performed for several configurations. Best performance was obtained for a single element wound armature with two field reversals. For a 60 kg projectile, 10.5 cm coil inner radius and 5.5 cm coil build, the velocity after 50 meters of launcher length (670 stages) exceeded 3.5 km/sec with an overall efficiency of about 45%. For the same parameters the solid and 16-element wound armatures reach a velocity of about 3.3 km/sec after 800 stages (60 meters of launcher length) but without field reversal. A velocity of 3.5 km/sec is possible after 60 meters of launcher length with the 16-element wound armature with one field reversal, but the temperature is close to the melting temperatureof aluminum.In all simulationswith a solid armatare, melting of some of the surface material occurs. However, it is shown that most of the melting occurs after contribution has been made to the forward going pressure, that is, melting does not affect the electrical performance of the launcher. The effect of coil firing time jitter on launcher performance is also considered and is found to be very o small for realisticperturbations. For + 2 g-sees random jitter, the reduction in the f'mal velocity for a 60 meter launcher with a solid armature is less than 0.1% and the increase in temperature is only 2%. This result holds for all types of armatures. % 1_STRtBUTION Ci: rt4ts [2OCUMENT IS UNLIMITED

IJERT-A Review on Technological Advancement in Electromagnetic Coil Gun System

International Journal of Engineering Research and Technology (IJERT), 2018

https://www.ijert.org/a-review-on-technological-advancement-in-electromagnetic-coil-gun-system https://www.ijert.org/research/a-review-on-technological-advancement-in-electromagnetic-coil-gun-system-IJERTCONV6IS15038.pdf A ground based electrically powered launcher could significantly reduce the complexity and cost of space launches for moderate weight payloads. This paper presents results of a study to estimate the required parameters. This study is based on electromagnetic gun technology which is constrained to a coaxial geometry to take advantage of the efficiency of closely coupled coils. Each coil is sequentially fired as the projectile moves down the bore. A hybrid power electronic system has been used for firing of a projectile without any chemical substances, without any loud noise and without fire. There's been speculation that, this paper has involved in this research. With this in mind, this paper humbly presents the crown jewel of the electronic weaponry, which brings a great revolution in the field of advanced weaponry systems in our country and makes us proud.

Applied and Theoretical Research on the Parameter-Dependent Efficiency of a Coilgun

This research paper focuses on determining the dependence of a coilgun's efficiency on its working parameters. Due to its working principal, the linear acceleration process of a ferromagnetic projectile can be described as a "shot". The ratio of the projectile's kinetic energy to the potential energy stored in the capacitors was used to calculate the efficiency of each shot. The equation of force pushing the projectile was derived theoretically. For health and safety reasons, measurements were taken with projectile speeds under 15m/s. A kinematic method was used to measure the speeds of the projectiles. Iron was chosen as the projectile material due to its ferromagnetic properties. After understanding the major factors that affect the coilgun's efficiency and by optimizing them, an efficiency value of 6.7% was achieved.

Design and evaluation of coils for a 50 mm diameter induction coilgun launcher

IEEE Transactions on Magnetics, 1995

Coilguns have the ability to provide magnetic pressure to projectiles which results in near constant acceleration. However, to achieve this performance and control projectile heating, significant constraints are placed on the design of the coils. We are developing coils to produce an effective projectile base pressure of 100 MPa (lkbar) as a step toward reaching base pressures of 200 MPa. The design uses a scalable technology applicable to the entire range of breech to muzzle coils of a multi-stage launcher. This paper presents the design of capacitor-driven coils for launching nominal 50 ram, 350 gram projectiles. Design criteria, constraints, mechanical stress analysis, launcher performance, and test results are discussed.

Coilgun design and evaluation without capacitor

Journal of Mechatronics and Artificial Intelligence in Engineering, 2020

Capacitors with high voltage and capacity values are used in most induction coilguns that are designed and constructed. The fact that capacitors are quite bulky and slow in energy transfer and how a coilgun can be made without using capacitors is the study subject of this article. Two and four coil gun samples were made to find the essential components of an electric gun, and the results are reported in this article. The accuracy of the results is also confirmed by FEMM analysis for these models. The harmony of experimental and theoretical results shows that smaller and low cost portable electrical weapons can be a powerful alternative to firearms in the future.

Modeling and Optimization of an Indirect Coil Gun for Launching Non-Magnetic Projectiles

Actuators, 2019

This article focuses on indirect coil guns used for launching non-magnetic objects. A mechatronic model, coupling electrical, mechanical, and electromagnetic models, is proposed. This model is applied to the optimization of a kicking system used on limited size robots for propelling real soccer balls at the RoboCup. Working with an existing coil gun, we show that fine tuning its setup, especially the initial position and the length of the non-magnetic plunger extension, leads to an increase in the ball speed of 30% compared to previous results.

Performance of an induction coil launcher

IEEE Transactions on Magnetics, 2000

Performanceof anelectromagnetic inductionlauncherisconsideredfor threetypesofarmatures. Theseare:Solid,I-element wound and16-element woundaluminumarmatures. "[heoneelement woundarmature has uniformcurrentdensitythroughout. Becauseof the uniformityof thecurrent density,the wound armaturecan withstandfieldreversal (workingagainstembeddedflux in the armature)andstill maintainlow temperature.Slingshot simulationswereperformedfor severalconfigurations. Bestperformance wasobtainedfor a singleelementwoundarmaturewithtwofieldreversals.Fora60kgprojectile,10.5cm coilinnerradiusand5.5 cmcoil build,thevelocityafter50 metersof launcherlength(670stages)exceeded3.5kin/seewithan overallefficiencyof about 45%.For the sameparametersthesolid and 16-element woundarmaturesreacha velocityof about3.3km/secafter800stages(60 metersoflauncherlength)butwithoutfieldreversal.Avelocityof 3.5km/secispossibleafter60 metersof launcherlengthwiththe 16-element woundarmaturewith one field reversal,but the temperatureis close to the meltingtemperatureof aluminum. In all simulationswith a solidarmature, meltingof someof the surfacematerial occurs.However, it is shownthatmostof the melting occursaftercontributionhas beenmade to the forwardgoingpressure,thatis,meltingdoesnotaffectthe electricalperformance of thelauncher. Theeffectofcoilfiringtimejitter on launcherperformance is alsoconsideredandisfoundtobe verysmallfor realistic. perturbations. For+ 2 g-secs randomjitter, thereductionin thefinalvelocityfor a 60meterlauncherwitha solidarmatureis less than0.1%and the increasein temperatureis only2%. This resultholdsfor all typesof armatures.