Name: methods for measuring the orientation and rotation rate of 3d-printed particles in turbulence
Uploaded: 2016-06-24T13:00:00.000+00:00
Duration: 12 min 34 s
Description: Watch this Scientific Journal Video about Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence at JoVE.com

我々は、我々が使用する画像圧縮システムを設計し、構築しスサンタWijesingheに感謝します。私たちは、NSFのグラントDMR-1208990からの支援を認めます。

<ol>
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Fluid Mech. 528, 87-118 (2005).</li><li>Frish, M., Webb, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+measurement+of+vorticity+by+optical+probe.">Direct measurement of vorticity by optical probe.</a> J. Fluid Mech. 107, 173-200 (1981).</li><li>Zimmerman, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tracking+the+dynamics+of+translation+and+absolute+orientation+of+a+sphere+in+a+turbulent+flow.">Tracking the dynamics of translation and absolute orientation of a sphere in a turbulent flow.</a> Rev. Sci. Instrum. 82 (3), 033906 (2011).</li><li>Zimmerman, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rotational+Intermittency+and+Turbulence+Induced+Lift+Experienced+by+Large+Particles+in+a+Turbulent+Flow.">Rotational Intermittency and Turbulence Induced Lift Experienced by Large Particles in a Turbulent Flow.</a> Phys. Rev. Lett. 106 (15), 154501 (2011).</li><li>Klein, S., Gibert, M. a. t. h. i. e. u., B&#233;rut, A., Bodenschatz, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simultaneous+3D+measurement+of+the+translation+and+rotation+of+finite-size+particles+and+the+flow+field+in+a+fully+developed+turbulent+water+flow.">Simultaneous 3D measurement of the translation and rotation of finite-size particles and the flow field in a fully developed turbulent water flow.</a> Meas. Sci. Technol. 24 (2), 1-10 (2013).</li><li>Bellani, G., Byron, M., Collignon, A., Meyer, C., Variano, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shape+effects+on+turbulent+modulation+by+large+nearly+neutrally+buoyant+particles.">Shape effects on turbulent modulation by large nearly neutrally buoyant particles.</a> J. Fluid Mech. 712, 41-60 (2012).</li></ol>

著者らは、開示することは一切競合する金融利害関係を持っていません。

渦と乱流流れの中の粒子の回転の測定は長い実験流体力学における重要な目標であると認識されています。乱流の小さな球体のソリッドボディの回転が半流体の渦度に等しいですが、球の回転対称性は、困難な彼らのソリッドボディ回転の直接測定を行いました。伝統的に、流体の渦度は、複雑な、マルチセンサ、熱線プローブ14を用いて測定しました。しかし、これらのセンサは、...

最近の刊行物では、乱流1中の粒子の回転運動を測定するための複数の細長いアームから作られた粒子の使用を導入しました。これらの粒子は、3Dプリンターを用いて製造することができ、正確に複数のカメラを使用してそれらの位置、姿勢、および回転速度を測定することができます。細長い本体論のツールを使用して、これらの粒子は、効果的な楕円体2に対応していることを示すことができ、これらの粒子の回転運動は、それぞれの有効な楕円のものと同一です。同じ長さの対称アームを有する粒子が球のように回転させます。そのような粒子は、その中心に取り付けられた3つの相互に垂直なアームを有するジャック、です。ジャックのアームの相対的長さを調整する任意の三軸楕円体の粒子と同等に形成することができます。一方のアームの長さはゼロに等しく設定されている場合、これは、その等価楕円ディスクでクロスを作成します。細長いからなる粒子腕は彼らの固体楕円対応の固体体積の小部分を取ります。その結果、密度が一致するように容易になり、よりゆっくりと沈降します。これは、固体楕円状の粒子と便利であるよりもはるかに大きい粒子の研究を可能にします。粒子は他の粒子からの光の小さな部分を遮断するため、また、撮像がはるかに高い粒子濃度で行うことができます。 本論文では、3D印刷粒子の製造および追跡するための方法が記載されています。複数のカメラから見たパーティクルの位置から球状粒子の並進運動を追跡するためのツールがいくつかのグループ3,4によって開発されてきました。パルサら 5は、複数のカメラから見た棒の位置及び姿勢を用いてロッドを追跡するためにこの方法を拡張しました。ここでは、多種多様な形状の粒子を作製し、それらの3D姿勢を再構成するための方法を提示します。これは、番目を提供しています電子の可能性は、新しいアプリケーションの広い範囲に複雑な形状を有する粒子の3Dトラッキングを拡張します。 この技術は、理由設計することができる粒子形状の広い範囲の更なる発展のために大きな可能性を秘めています。これらの形状の多くはプランクトン、種子、および氷の結晶が形状の広大な配列に来る環境フロー、直接アプリケーションを持っています。粒子の回転および乱流6の基本的な小規模の特性との間の接続は、これらの粒子の回転の研究では、乱流カスケードプロセスを見ての新しい方法を提供することを示唆しています。

<table><tbody><tr><td>Condor Nd:YAG 50 W laser</td><td>Quantronics</td><td>532-30-M</td><td></td></tr><tr><td>High speed camera</td><td>Basler</td><td>A504k</td><td></td></tr><tr><td>High speed camera</td><td>Mikrotron</td><td>EoSens Mc1362</td><td></td></tr><tr><td>Rhodamine-B</td><td>ScienceLab.com</td><td>SLR1465</td><td></td></tr><tr><td>Sodium Hydroxide</td><td>Macron</td><td>7708</td><td>Pellets.</td></tr><tr><td>500 Connex 3D printer</td><td>Objet</td><td></td><td>Used to make smaller particles. Particles ordered from RP+M (rapid prototyping plus manufacturing).</td></tr><tr><td>VeroClear</td><td>Stratasys</td><td>RGD810</td><td>Objet build material.</td></tr><tr><td>Clear Form 1 Photopolymer Resin</td><td>Formlabs</td><td></td><td></td></tr><tr><td>Cylindrical and spherical lenses</td><td></td><td></td><td></td></tr><tr><td>200 mm macro camera lenses</td><td></td><td></td><td>F-mount.</td></tr><tr><td>Ultrasonic bath</td><td>Sonicator</td><td></td><td></td></tr><tr><td>Calcium Chloride</td><td>Spectrum Chemical Mfg. Corp.</td><td>CAS 10043-52-2</td><td>Pellets.</td></tr><tr><td>LabVIEW System Design Software</td><td>National Instruments</td><td></td><td>Used to trigger cameras, control grid, and trigger laser.</td></tr><tr><td>XCAP Software</td><td>EPIX</td><td></td><td>Used with LabVIEW to trigger cameras.</td></tr><tr><td>MATLAB</td><td>Mathworks</td><td></td><td>Used for all image and data analysis. Programs for extracting 3D orientations from multiple images are included with this publication.</td></tr><tr><td>OpenPTV: Open Source Particle Tracking Velocimetry</td><td>OpenPTV Consortium</td><td></td><td></td></tr><tr><td>ParaView</td><td>Kitware</td><td></td><td></td></tr><tr><td>AutoCAD</td><td>AutoDesk</td><td></td><td>Used to design all particles. Screenshots of particle designs are all of AutoCAD.</td></tr><tr><td>Mesh with 0.040 x 0.053 inch holes</td><td>Industrial Netting</td><td>XN5170&amp;ndash;43.5</td><td></td></tr><tr><td>Camera filters</td><td>Schneider Optics</td><td>B+W 040M</td><td></td></tr></tbody></table>

methods for measuring the orientation and rotation rate of 3d-printed particles in turbulence

実験方法は、乱流の流体の流れに異方性粒子の回転および並進運動を測定するために提示されています。三次元印刷技術は、共通の中心部に接続された細長いアームを有する粒子を製造するために使用されます。探検形状が十字（2垂直棒）、ジャック（3垂直棒）、三和音（三角面対称で3ロッド）、および四分子（四面体対称で4本のアーム）です。万蛍光染色された粒子のために製造する方法が記載されています。それらの配向とソリッドボディ回転速度の時間分解測定は、この比較的低いレイノルズ数の流れでRλ= 91とグリッドを振動間乱流におけるそれらの動きの4同期ビデオから得られ、移流粒子が十分に小さいですそれらは楕円トレーサー粒子を近似します。我々は、粒子の位置及び姿勢の時間分解3D軌道の存在の結果としてよく彼らの回転速度の測定のような。

図3aは、その軌跡（ 図3c）の部分から得られたオイラー角のプロット上我々のカメラの一つから四分子の画像を示しています。 図3bに、プロトコル5に記載の方位発見アルゴリズムの結果- 5.3は、四分子画像に重畳されています。 図3aの四分子の腕はモデル（プロトコル5.1.3.1）を作成するために使用される単純な強度?...

Watch this Scientific Journal Video about Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence at JoVE.com

Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence

We use 3D printing to fabricate anisotropic particles in the shapes of jacks, crosses, tetrads, and triads, whose alignments and rotations in turbulent fluid flow can be measured from multiple simultaneous video images.

乱流で3Dプリント粒子の配向および回転速度を測定するための方法

Experimental methods are presented for measuring the rotational and translational motion of anisotropic particles in turbulent fluid flows. 3D printing ...

methods-for-measuring-orientation-rotation-rate-3d-printed-particles

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3-Dimensional Kinetics of a Rigid Body

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10.0K ビュー.  Wesleyan University. We use 3D printing to fabricate anisotropic particles in the shapes of jacks, crosses, tetrads, and triads, whose alignments and rotations in turbulent fluid flow can be measured from multiple simultaneous video images.

ビデオ: Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence

Encapsulation and Permeability Characteristics of Plasma Polymerized Hollow Particles

In this protocol, core-shell nanostructures are synthesized by plasma enhanced chemical vapor deposition. We produce an amorphous barrier by plasma polymerization of isopropanol on various solid substrates, including silica and potassium chloride. This versatile technique is used to treat nanoparticles and nanopowders with sizes ranging from 37 nm to 1 micron, by depositing films whose thickness can be anywhere from 1 nm to upwards of 100 nm. Dissolution of the core allows us to study the rate of permeation through the film. In these experiments, we determine the diffusion coefficient of KCl through the barrier film by coating KCL nanocrystals and subsequently monitoring the ionic conductivity of the coated particles suspended in water. The primary interest in this process is the encapsulation and delayed release of solutes. The thickness of the shell is one of the independent variables by which we control the rate of release. It has a strong effect on the rate of release, which increases from a six-hour release (shell thickness is 20 nm) to a long-term release over 30 days (shell thickness is 95 nm). The release profile shows a characteristic behavior: a fast release (35% of the final materials) during the first five minutes after the beginning of the dissolution, and a slower release till all of the core materials come out.

We have used plasma enhanced chemical vapor deposition to deposit thin films ranging from a few nm to several 100 nm on nano-sized particles of various materials. We subsequently etch the core material to produce hollow nanoshells whose permeability is controlled by the thickness of the shell. We characterize the permeability of these coatings to small solutes and demonstrate that these barriers can provide sustained release of the core material over several days.

プラズマ重合中空粒子のカプセル化と透水特性

In this protocol, core-shell nanostructures are synthesized by plasma enhanced chemical vapor deposition. We produce an amorphous barrier by plasma ...

工学

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids

An experimental study is performed to measure the terminal settling velocities of spherical particles in surfactant based shear thinning viscoelastic (VES) fluids. The measurements are made for particles settling in unbounded fluids&#160;and fluids between parallel walls. VES fluids over a wide range of rheological properties are prepared and rheologically characterized. The rheological characterization involves steady shear-viscosity and dynamic oscillatory-shear measurements to quantify the viscous and elastic properties respectively. The settling velocities under unbounded conditions are measured in beakers having diameters at least 25x the diameter of particles. For measuring settling velocities between parallel walls, two experimental cells with different wall spacing are constructed. Spherical particles of varying sizes are gently dropped in the fluids and allowed to settle. The process is recorded with a high resolution video camera and the trajectory of the particle is recorded using image analysis software. Terminal settling velocities are calculated from the data.
The impact of elasticity on settling velocity in unbounded fluids is quantified by comparing the experimental settling velocity to the settling velocity calculated by the inelastic drag predictions of Renaud et al.1&#160;Results show that elasticity of fluids can increase or decrease the settling velocity. The magnitude of reduction/increase is a function of the rheological properties of the fluids and properties of particles. Confining walls are observed to cause a retardation effect on settling and the retardation is measured in terms of wall factors.

This paper demonstrates the experimental procedure to measure terminal settling velocities of spherical particles in surfactant-based shear thinning viscoelastic fluids. Fluids over a wide range of rheological properties are prepared and settling velocities are measured for a range of particle sizes in unbounded fluids and fluids between parallel walls.

閉じ込められていない狭間性界面活性剤ベースの剪断間粘弾性流体における球状粒子の沈降速度の実験的測定

An experimental study is performed to measure the terminal settling velocities of spherical particles in surfactant based shear thinning viscoelastic ...

Automation of Mode Locking in a Nonlinear Polarization Rotation Fiber Laser through Output Polarization Measurements

When a laser is mode-locked, it emits a train of ultra-short pulses at a repetition rate determined by the laser cavity length. This article outlines a new and inexpensive procedure to force mode locking in a pre-adjusted nonlinear polarization rotation fiber laser. This procedure is based on the detection of a sudden change in the output polarization state when mode locking occurs. This change is used to command the alignment of the intra-cavity polarization controller in order to find mode-locking conditions. More specifically, the value of the first Stokes parameter varies when the angle of the polarization controller is swept and, moreover, it undergoes an abrupt variation when the laser enters the mode-locked state. Monitoring this abrupt variation provides a practical easy-to-detect signal that can be used to command the alignment of the polarization controller and drive the laser towards mode locking. This monitoring is achieved by feeding a small portion of the signal to a polarization analyzer measuring the first Stokes parameter. A sudden change in the read out of this parameter from the analyzer will occur when the laser enters the mode-locked state. At this moment, the required angle of the polarization controller is kept fixed. The alignment is completed. This procedure provides an alternate way to existing automating procedures that use equipment such as an optical spectrum analyzer, an RF spectrum analyzer, a photodiode connected to an electronic pulse-counter or a nonlinear detecting scheme based on two-photon absorption or second harmonic generation. It is suitable for lasers mode locked by nonlinear polarization rotation. It is relatively easy to implement, it requires inexpensive means, especially at a wavelength of 1550 nm, and it lowers the production and operation costs incurred in comparison to the above-mentioned techniques.

A protocol to detect and automate mode locking in a pre-adjusted nonlinear polarization rotation fiber laser is presented. The detection of a sudden change in the output polarization state when mode locking occurs is used to command the alignment of an intra-cavity polarization controller in order to find mode-locking conditions.

出力偏光測定を通じて非線形偏波回転ファイバレーザにおけるモードロックの自動化

When a laser is mode-locked, it emits a train of ultra-short pulses at a repetition rate determined by the laser cavity length. This article outlines a ...

Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow

3D-PTV is a quantitative flow measurement technique that aims to track the Lagrangian paths of a set of particles in three dimensions using stereoscopic recording of image sequences. The basic components, features, constraints and optimization tips of a 3D-PTV topology consisting of a high-speed camera with a four-view splitter are described and discussed in this article. The technique is applied to the intermediate flow field (5 &#60;x/d &#60;25) of a circular jet at Re &#8776; 7,000. Lagrangian flow features and turbulence quantities in an Eulerian frame are estimated around ten diameters downstream of the jet origin and at various radial distances from the jet core. Lagrangian properties include trajectory, velocity and acceleration of selected particles as well as curvature of the flow path, which are obtained from the Frenet-Serret equation. Estimation of the 3D velocity and turbulence fields around the jet core axis at a cross-plane located at ten diameters downstream of the jet is compared with literature, and the power spectrum of the large-scale streamwise velocity motions is obtained at various radial distances from the jet core.

A three-dimensional particle tracking velocimetry (3D-PTV) system based on a high-speed camera with a four-view splitter is described here. The technique is applied to a jet flow from a circular pipe in the vicinity of ten diameters downstream at Reynolds number Re &#8776; 7,000.

ジェット流の場合：乱流のアプリケーションのための3次元粒子追跡流速

3D-PTV is a quantitative flow measurement technique that aims to track the Lagrangian paths of a set of particles in three dimensions using stereoscopic ...

Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions

Two different experimental methods for determining the threshold of particle motion as a function of geometrical properties of the bed from laminar to turbulent flow conditions are presented. For that purpose, the incipient motion of a single bead is studied on regular substrates that consist of a monolayer of fixed spheres of uniform size that are regularly arranged in triangular and quadratic symmetries. The threshold is characterized by the critical Shields number. The criterion for the onset of motion is defined as the displacement from the original equilibrium position to the neighboring one. The displacement and the mode of motion are identified with an imaging system. The laminar flow is induced using a rotational rheometer with a parallel disk configuration. The shear Reynolds number remains below 1. The turbulent flow is induced in a low-speed wind tunnel with open jet test section. The air velocity is regulated with a frequency converter on the blower fan. The velocity profile is measured with a hot wire probe connected to a hot film anemometer. The shear Reynolds number ranges between 40 and 150. The logarithmic velocity law and the modified wall law presented by Rotta are used to infer the shear velocity from the experimental data. The latter is of special interest when the mobile bead is partially exposed to the turbulent flow in the so-called hydraulically transitional flow regime. The shear stress is estimated at onset of motion. Some illustrative results showing the strong impact of the angle of repose, and the exposure of the bead to shear flow are represented in both regimes.

Two different methods for characterizing the incipient particle motion of a single bead as a function of the sediment bed geometry from laminar to turbulent flow are presented.

視覚に基づいた正規の基板の初期粒子の運動特性: 層流乱流の条件から

Two different experimental methods for determining the threshold of particle motion as a function of geometrical properties of the bed from laminar to ...

Simultaneous Measurement of Turbulence and Particle Kinematics Using Flow Imaging Techniques

Numerous problems in scientific and engineering fields involve understanding the kinematics of particles in turbulent flows, such as contaminants, marine micro-organisms, and/or sediments in the ocean, or fluidized bed reactors and combustion processes in engineered systems. In order to study the effect of turbulence on the kinematics of particles in such flows, simultaneous measurements of both the flow and particle kinematics are required. Non-intrusive, optical flow measurement techniques for measuring turbulence, or for tracking particles, exist but measuring both simultaneously can be challenging due to interference between the techniques. The method presented herein provides a low cost and relatively simple method to make simultaneous measurements of the flow and particle kinematics. A cross section of the flow is measured using a particle image velocimetry (PIV) technique, which provides two components of velocity in the measurement plane. This technique utilizes a pulsed-laser for illumination of the seeded flow field that is imaged by a digital camera. The particle kinematics are simultaneously imaged using a light emitting diode (LED) line light that illuminates a planar cross section of the flow that overlaps with the PIV field-of-view (FOV). The line light is of low enough power that it does not affect the PIV measurements, but powerful enough to illuminate the larger particles of interest imaged using the high-speed camera. High-speed images that contain the laser pulses from the PIV technique are easily filtered by examining the summed intensity level of each high-speed image. By making the frame rate of the high-speed camera incommensurate with that of the PIV camera frame rate, the number of contaminated frames in the high-speed time series can be minimized. The technique is suitable for mean flows that are predominantly two-dimensional, contain particles that are at least 5 times the mean diameter of the PIV seeding tracers, and are low in concentration.

The technique described herein offers a low cost and relatively simple method to simultaneously measure particle kinematics and turbulence in flows with low particle concentrations. The turbulence is measured using particle image velocimetry (PIV), and particle kinematics are calculated from images obtained with a high-speed camera in an overlapping field-of-view.

フロー イメージング技術を用いた粒子運動と乱流の同時測定

Numerous problems in scientific and engineering fields involve understanding the kinematics of particles in turbulent flows, such as contaminants, marine ...

3D Printing - Evaluating Particle Emissions of a 3D Printing Pen

Three-dimensional (3D) printing as a type of additive manufacturing shows continuing increase in application and consumer popularity. The fused filament fabrication (FFF) is an inexpensive method used most frequently by consumers. Studies with 3D printers have shown that during the printing process particulate and volatile substances are released. Handheld 3D printing pens also use the FFF method but the consumer&#8217;s proximity to the 3D pens gives reason to higher exposure compared to a 3D printer. At the same time, 3D printing pens are often marketed for children who could be more sensitive to the printing emission. The aim of this study was to implement a low cost method to analyze the emissions of 3D printing pens. Polylactide (PLA) and acrylonitrile butadiene styrene (ABS) filaments of different colors were tested. In addition, filaments containing metal and carbon nanotubes (CNTs) were analyzed. An 18.5 L chamber and sampling close to the emission source was used to characterize emissions and concentrations near the breathing zone of the user.
Particle emissions and particle size distributions were measured and the potential release of metal particles and CNTs investigated. Particle number concentrations were found in a range of 105 - 106 particles/cm3, which is comparable to previous reports from 3D printers. Transmission electron microscopy (TEM) analysis showed nanoparticles of the different thermoplastic materials as well as of metal particles and CNTs. High contents of metal were observed by inductively coupled plasma mass spectrometry (ICP-MS).
These results call for a cautious use of 3D pens due to potential risk to the consumers.

This protocol presents a method to analyze the emission of 3D printing pens. Particle concentration and particle size distribution of the released particle is measured. Released particles are further analyzed with transmission electron microscopy (TEM). Metal content in filaments is quantified by inductively coupled plasma mass spectrometry (ICP-MS).

3D プリント - 3D プリント ペンのパーティクル放出の評価

Three-dimensional (3D) printing as a type of additive manufacturing shows continuing increase in application and consumer popularity. The fused filament ...

Frugal Imaging Technique of Capillary Flow Through Three-Dimensional Polymeric Printing Powders

The development of novel imaging techniques of molecular and colloidal transport, including nanoparticles, is an area of active investigation in microfluidic and millifluidic studies. With the advent of three-dimensional (3D) printing, a new domain of materials has emerged, thereby increasing the demand for novel polymers. Specifically, polymeric powders, with average particle sizes on the order of a micron, are experiencing a growing interest from academic and industrial communities. Controlling material tunability at the mesoscopic to microscopic length scales creates opportunities to develop innovative materials, such as gradient materials. Recently, a need for micron-sized polymeric powders has been growing, as clear applications for the material are developing. Three-dimensional printing provides a high-throughput process with a direct link to new applications, driving investigations into the physio-chemical and transport interactions on a mesoscale. The protocol that is discussed in this article provides a non-invasive technique to image fluid flow in packed powder beds, providing high temporal and spatial resolution while leveraging mobile technology that is readily available from mobile devices, such as smartphones. By utilizing a common mobile device, the imaging costs that would normally be associated with an optical microscope are eliminated, resulting in a frugal-science approach. The proposed protocol has successfully characterized a variety of combinations of fluids and powders, creating a diagnostic platform for quickly imaging and identifying an optimal combination of fluid and powder.

The proposed technique will provide a novel, efficient, frugal, and non-invasive approach for imaging fluidic flow through a packed powder bed, yielding high spatial and temporal resolution.

三次元高分子印刷用粉末を通る毛細管流の倹約イメージング技術

The development of novel imaging techniques of molecular and colloidal transport, including nanoparticles, is an area of active investigation in ...

3Dプリンティング品質を最適化するためのポリマーダイナミクスの可視化

Real-Time Imaging of Bonding in 3D-Printed Layers

In recent times, 3D printing technology has revolutionized our ability to design and produce products, but optimizing the print quality can be challenging. The process of extrusion 3D printing involves pressuring molten material through a thin nozzle and depositing it onto previously extruded material. This method relies on bonding between the consecutive layers to create a strong and visually appealing final product. This is no easy task, as many parameters, such as the nozzle temperature, layer thickness, and printing speed, must be fine-tuned to achieve optimal results. In this study, a method for visualizing the polymer dynamics during extrusion is presented, giving insight into the layer bonding process. Using laser speckle imaging, the plastic flow and fusion can be resolved non-invasively, internally, and with high spatiotemporal resolution. This measurement, which is easy to perform, provides an in-depth understanding of the underlying mechanics influencing the final print quality. This methodology was tested with a range of cooling fan speeds, and the results showed increased polymer motion with lower fan speeds and, thus, explained the poor printing quality when the cooling fan was turned off. These findings show that this methodology allows for optimizing the printing settings and understanding the material behavior. This information can be used for the development and testing of novel printing materials or advanced slicing procedures. With this approach, a deeper understanding of extrusion can be built to take 3D printing to the next level.

著者スポットライト:3Dプリントレイヤーにおけるボンディングのリアルタイムイメージング  

With a non-invasive and real-time technique, nanoscopic polymer motion inside a polymer filament is imaged during 3D printing. Fine-tuning this motion is crucial for producing constructs with optimal performance and appearance. This method reaches the core of plastic layer fusion, thus offering insights into optimal printing conditions and material design criteria.

乱流で3Dプリント粒子の配向および回転速度を測定するための方法

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プラズマ重合中空粒子のカプセル化と透水特性

閉じ込められていない狭間性界面活性剤ベースの剪断間粘弾性流体における球状粒子の沈降速度の実験的測定

出力偏光測定を通じて非線形偏波回転ファイバレーザにおけるモードロックの自動化

ジェット流の場合：乱流のアプリケーションのための3次元粒子追跡流速

視覚に基づいた正規の基板の初期粒子の運動特性: 層流乱流の条件から

フローイメージング技術を用いた粒子運動と乱流の同時測定

3D プリント - 3D プリントペンのパーティクル放出の評価

三次元高分子印刷用粉末を通る毛細管流の倹約イメージング技術

3Dプリント層における接合のリアルタイムイメージング

3Dプリント層における接合のリアルタイムイメージング

乱流で3Dプリント粒子の配向および回転速度を測定するための方法

要約

さらに動画を探す

この動画の章

プラズマ重合中空粒子のカプセル化と透水特性

閉じ込められていない狭間性界面活性剤ベースの剪断間粘弾性流体における球状粒子の沈降速度の実験的測定

出力偏光測定を通じて非線形偏波回転ファイバレーザにおけるモードロックの自動化

ジェット流の場合：乱流のアプリケーションのための3次元粒子追跡流速

視覚に基づいた正規の基板の初期粒子の運動特性: 層流乱流の条件から

フロー イメージング技術を用いた粒子運動と乱流の同時測定

3D プリント - 3D プリント ペンのパーティクル放出の評価

三次元高分子印刷用粉末を通る毛細管流の倹約イメージング技術

3Dプリント層における接合のリアルタイムイメージング

3Dプリント層における接合のリアルタイムイメージング

フローイメージング技術を用いた粒子運動と乱流の同時測定

3D プリント - 3D プリントペンのパーティクル放出の評価