Method for generating manufacturable, topology-optimized parts for Laminated Layer Manufacturing

AbstractCystic echinococcosis is a zoonotic disease caused by the metacestode of Echinococcus granulosus sensu lato. The disease is characterized by the development of cystic structures inside viscera of the intermediate host, mainly liver and lungs. These cysts are formed by three layers: germinal, laminated, and adventitial layer, the latter being the local host immune response. Metacestodes that develop protoscoleces, the infective stage to the definitive host, are termed fertile, whereas cysts that do not produce protoscoleces are termed non-fertile. Sheep usually harbor fertile cysts while cattle usually harbor non-fertile cysts. Adventitial layers with fibrotic resolution are associated to fertile cysts, whereas a granulomatous reaction is associated with non-fertile cysts. The aim of this study was to analyze cellular distribution in the adventitial layer of fertile and non-fertile E. granulosus sensu stricto cysts found in liver and lungs of cattle and sheep. A total of 418 cysts were analyzed, 203 from cattle (8 fertile and 195 non-fertile) and 215 from sheep (64 fertile and 151 non-fertile). Fertile cysts from cattle showed mixed patterns of response, with fibrotic resolution and presence of granulomatous response in direct contact with the laminated layer, while sheep fertile cysts always displayed fibrotic resolution next to the laminated layer. Cattle non-fertile cysts display a granulomatous reaction in direct contact with the laminated layer, whereas sheep non-fertile cysts display a granulomatous reaction, but in direct contact with the fibrotic resolution. This shows that cattle and sheep cystic echinococcosis cysts have distinct local immune response patterns, which are associated to metacestode fertility.

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Axially symmetric problems of heat conduction in a periodically laminated layer with vertical cylindrical hole

International Communications in Heat and Mass Transfer ◽

10.1016/j.icheatmasstransfer.2010.12.018 ◽

2011 ◽

Vol 38 (4) ◽

pp. 410-417 ◽

Cited By ~ 3

Author(s):

Stanisław J. Matysiak ◽

Dariusz M. Perkowski

Keyword(s):

Heat Conduction ◽

Cylindrical Hole ◽

Axially Symmetric ◽

Laminated Layer

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A study of metallurgical and processing approach of additive layer manufacturing processes for metal tool components production

Materials Today Proceedings ◽

10.1016/j.matpr.2021.05.103 ◽

2021 ◽

Author(s):

Rohit Pandey ◽

Hardik B. Ramani

Keyword(s):

Manufacturing Processes ◽

Additive Layer Manufacturing ◽

Processing Approach ◽

Layer Manufacturing

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An intact laminated layer is important for the establishment of secondary Echinococcus multilocularis infection

Parasitology Research ◽

10.1007/s00436-002-0659-7 ◽

2002 ◽

Vol 88 (9) ◽

pp. 822-828 ◽

Cited By ~ 37

Author(s):

Bruno Gottstein ◽

Wen Dai ◽

Mirjam Walker ◽

Marianne Stettler ◽

Norbert Müller ◽

...

Keyword(s):

Echinococcus Multilocularis ◽

Laminated Layer

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Product Model Preparation and Processing for Micromanufacturing

Journal of Computing and Information Science in Engineering ◽

10.1115/1.2904939 ◽

2008 ◽

Vol 8 (2) ◽

Author(s):

Chao-Yaug Liao ◽

Jean-Claude Léon ◽

Cédric Masclet ◽

Michel Bouriau ◽

Patrice L. Baldeck ◽

...

Keyword(s):

Laser Beam ◽

Computer Aided Design ◽

Welding Process ◽

Product Model ◽

Processing Scheme ◽

Proposed Model ◽

Layer Manufacturing ◽

Manifold Models ◽

Model Preparation ◽

Aided Design

Based on the two-photon polymerization technique, an analysis of product shapes is performed so that their digital manufacturing models can be efficiently processed for micromanufacture. To describe microstructures, this analysis shows that nonmanifold models are of interest. These models can be intuitively understood as combinations of wires, surfaces, and volumes. Minimum acceptable wall thickness, wire dimension, and laser density of energy are among the elements justifying this category of models. Taking into account this requirement, a model preparation and processing scheme is proposed that widens the laser beam trajectories with a concept of extended layer manufacturing technique. A tessellation process suited for non-manifold models has been developed for computer-aided design models imported from standard for the exchange of product files. After tessellation, several polyhedral subdomains form a nonmanifold polyhedron. To plan the trajectories of the laser beam, adaptive slicing and global 3D hatching processes as well as a “welding” process (for joining subdomains of different dimensionality) have been combined. Finally, two nonmanifold microstructures are fabricated according to the proposed model preparation and processing scheme.

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Topology Optimization, Additive Layer Manufacturing, and Experimental Testing of an Air-Cooled Heat Sink

Journal of Mechanical Design ◽

10.1115/1.4030989 ◽

2015 ◽

Vol 137 (11) ◽

Cited By ~ 109

Author(s):

Ercan M. Dede ◽

Shailesh N. Joshi ◽

Feng Zhou

Keyword(s):

Topology Optimization ◽

Heat Sink ◽

Computer Aided Design ◽

Experimental Testing ◽

Jet Impingement ◽

Coefficient Of Performance ◽

Air Cooling ◽

Additive Layer Manufacturing ◽

Cloud Data ◽

Layer Manufacturing

Topology optimization of an air-cooled heat sink considering heat conduction plus side-surface convection is presented. The optimization formulation is explained along with multiple design examples. A postprocessing procedure is described to synthesize manifold or “water-tight” solid model computer-aided design (CAD) geometry from three-dimensional (3D) point-cloud data extracted from the optimization result. Using this process, a heat sink is optimized for confined jet impingement air cooling. A prototype structure is fabricated out of AlSi12 using additive layer manufacturing (ALM). The heat transfer and fluid flow performance of the optimized heat sink are experimentally evaluated, and the results are compared with benchmark plate and pin-fin heat sink geometries that are conventionally machined out of aluminum and copper. In two separate test cases, the experimental results indicate that the optimized ALM heat sink design has a higher coefficient of performance (COP) relative to the benchmark heat sink designs.

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Additive Manufacturing of Flexible Material for Pneumatic Actuators Application

Actuators ◽

10.3390/act10070161 ◽

2021 ◽

Vol 10 (7) ◽

pp. 161

Author(s):

Miranda Fateri ◽

João Falcão Carneiro ◽

Achim Frick ◽

João Bravo Pinto ◽

Fernando Gomes de Almeida

Keyword(s):

Material Properties ◽

Thermoplastic Polyurethane ◽

Scanning Calorimetry ◽

Pneumatic Actuators ◽

Geometry Design ◽

Flexible Material ◽

Layer Manufacturing ◽

Thermoplastic Polyurethane Elastomer ◽

Manufacturing Techniques ◽

Circular Design

In this paper, endurance of peristaltic linear pneumatic actuators was studied using different hose geometries. Towards this goal, different hose geometries were additively manufactured using Fused Layer Manufacturing techniques of Thermoplastic Polyurethane Elastomer. Material properties of the elastomer were studied using Differential Scanning Calorimetry and the tensile test. The relations between the sample’s print temperature and build direction on the actuator endurance were investigated. Lastly, the relation between the geometry design of the PLPA actuator and its endurance is also discussed. Based on this methodology, authors present results showing that the use of a customized shaped hose with geometrical reinforcement at sides leads to a considerable rise in the hose endurance, when compared with the conventional circular design.

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