3D Crystal Arc Awards & Desktop Gifts

We offer these impressive Crystal Awards & Desktop Gifts in multiple sizes and designs to suit any budget. They are perfect for celebrating your big achievements like corporate events, academic accomplishments or sports competitions.

Three-dimensional (3D) emission tomography allows acquisition of volumetric plasma luminosity field measurements. This enables quantification of gliding arc characteristics not easily accessible in two-dimensional measurements.

Flowrates

Unlike the conventional 2D GAD operating under restrike mode controlled by ignition-gliding-extinction mechanism, the 3D Crystal Arc operates under a self-sustaining oscillation process with continuous gliding motion. This special behavior is attributed to the fact that the arc continuously sheds the caudal part of the arc and regenerates new one at the shortest electrode gap.

The effect of gas flow rate and precursor concentration on the structure of carbon nanosheets was explored in two routes, including chemical vapor dissociation and graphite exfoliation. In the former route, the product morphology is influenced by the energy consumed as well as the SEI and residence time of reactant vapor.

PIV analysis of the free jet flow at torch A with and without an arc demonstrates that the arc influences the flow mainly in the direct vicinity of the plasma process and above the work piece. The resulting mean flow maps show that the velocity significantly increases right beside the arc and decreases further away from it.

Arc Curvature

The arcs exhibit a large, k-dependent relative magnetization splitting that can be explained by a broken topological insulator symmetry as well as by hybridization with substrate states44. Our theory also predicts that the spin texture of the arcs will differ significantly from that of conventional topological surfaces, being strongly influenced by both the p-orbital symmetry and a lack of spatial inversion symmetry at the atom interface.

In the supplementary material, we show the results from a computational study that confirms this experimental observation. The calculated phase-space distribution of the mixed Berry curvature (Omega _yxwidehatbfmbfk) reveals that the arcs have a very different sign near the end points.

Moreover, we compare the calculated arc path with the 3D tomographic reconstruction of the gliding arc. As expected, the 2D projected length underestimates the 3D length. A strong correlation between swept angle and 3D length is observed with increasing air flow rates. A proportionality line illustrating this increase is shown in Fig. 4a, with the slope changing from 0.19 up to 0.26.

Arc Overlap

This approach allows the printer to print very large overhangs that could not be printed before without support structures. However, it takes a long time to do so because the arcs overlap a lot and need to be printed at low speeds so that they can fuse to each other and not droop.

3D tomographic reconstructions at different air flow rates show that arc volume decreases with increasing air flow, as shown in Fig. 4. This trend is attributed to increased turbulence, which shortens arc residence times and therefore reduces the number of locally excited species, leading to a reduction in arc volume. Moreover, arcs that overlap in 2D projections as depicted in Fig. 4(b) will contribute to length underestimation in 2D measurements and may invalidate some arcs for evaluation. Proportionality lines computed between swept-angle and 3D length, represented as line slopes, increase with increased flow cases. This is expected, since higher turbulence will also lead to more overlapping paths.

Arc Pathways

3D emission tomography was experimentally applied to gliding arc plasma to acquire volumetric luminosity information of the probed volume. The in-house developed tomographic method reconstructs the arc plasma luminosity field from the acquired images and provides quantification of features that are not easily accessible in two-dimensional measurements.

Resulting tomographic reconstructions of the arc luminosity field showed good field reconstruction quality with expected arc topologies captured. Quantified arc length distributions demonstrated that the mean 3D length initially increased with increasing air flow, reaching around 190 mm for case 2. At higher flows, the arc length began decreasing and reached 160 mm for case 3.

A strong correlation between swept-angle and reconstructed length was identified where proportionality lines computed by using the same method as in Figs. 3(b)-3(e) are displayed, highlighting line slopes. Moreover, the percentage of arcs with overlap in 2D projections increased with increasing air flow, reaching up to 50% for the highest tested flow case (case 4).