Large-scale true tri-axial fracturing experimental investigation on diversion behavior of fiber using 3D printing model of rock formation

2019 ◽  
Vol 181 ◽  
pp. 106171 ◽  
Author(s):  
Lufeng Zhang ◽  
Fujian Zhou ◽  
Jianye Mou ◽  
Maysam Pournik ◽  
Shaodan Tao ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
3D Printing ◽  
Large Scale ◽  
Rock Formation

scholarly journals Using a Cable-Driven Parallel Robot with Applications in 3D Concrete Printing

2021 ◽  
Vol 11 (2) ◽  
pp. 563
Author(s):  
Tuong Phuoc Tho ◽  
Nguyen Truong Thinh
Keyword(s):  
3D Printing ◽  
Large Scale ◽  
Trust Region ◽  
Parallel Robot ◽  
Inverse Kinematic ◽  
Programming Algorithm ◽  
Construction Time ◽  
Inverse Kinematic Problem ◽  
Robot Configuration ◽  
Printing Method

In construction, a large-scale 3D printing method for construction is used to build houses quickly, based on Computerized Aid Design. Currently, the construction industry is beginning to apply quite a lot of 3D printing technologies to create buildings that require a quick construction time and complex structures that classical methods cannot implement. In this paper, a Cable-Driven Parallel Robot (CDPR) is described for the 3D printing of concrete for building a house. The CDPR structures are designed to be suitable for 3D printing in a large workspace. A linear programming algorithm was used to quickly calculate the inverse kinematic problem with the force equilibrium condition for the moving platform; this method is suitable for the flexible configuration of a CDPR corresponding to the various spaces. Cable sagging was also analyzed by the Trust-Region-Dogleg algorithm to increase the accuracy of the inverse kinematic problem for controlling the robot to perform basic trajectory interpolation movements. The paper also covers the design and analysis of a concrete extruder for the 3D printing method. The analytical results are experimented with based on a prototype of the CDPR to evaluate the work ability and suitability of this design. The results show that this design is suitable for 3D printing in construction, with high precision and a stable trajectory printing. The robot configuration can be easily adjusted and calculated to suit the construction space, while maintaining rigidity as well as an adequate operating space. The actuators are compact, easy to disassemble and move, and capable of accommodating a wide variety of dimensions.

scholarly journals Polyamide 12/Multiwalled Carbon Nanotube and Carbon Black Nanocomposites Manufactured by 3D Printing Fused Filament Fabrication: A Comparison of the Electrical, Thermoelectric, and Mechanical Properties

2021 ◽  
Vol 7 (2) ◽  
pp. 38
Author(s):  
Nectarios Vidakis ◽  
Markos Petousis ◽  
Lazaros Tzounis ◽  
Emmanuel Velidakis ◽  
Nikolaos Mountakis ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
3D Printing ◽  
Carbon Black ◽  
Large Scale ◽  
Fracture Mechanisms ◽  
Fused Filament Fabrication ◽  
Melt Mixing ◽  
Multiwalled Carbon ◽  
Electrically Conductive ◽  
Polyamide 12

In this study, nanocomposites with polyamide 12 (PA12) as the polymer matrix and multiwalled carbon nanotubes (MWCNTs) and carbon black (CB) at different loadings (2.5, 5.0, and 10.0 wt.%) as fillers, were produced in 3D printing filament form by melt mixing extrusion process. The filament was then used to build specimens with the fused filament fabrication (FFF) three-dimensional (3D) printing process. The aim was to produce by FFF 3D printing, electrically conductive and thermoelectric functional specimens with enhanced mechanical properties. All nanocomposites’ samples were electrically conductive at filler loadings above the electrical percolation threshold. The highest thermoelectric performance was obtained for the PA12/CNT nanocomposite at 10.0 wt.%. The static tensile and flexural mechanical properties, as well as the Charpy’s impact and Vickers microhardness, were determined. The highest improvement in mechanical properties was observed for the PA12/CNT nanocomposites at 5.0 wt.% filler loading. The fracture mechanisms were identified by fractographic analyses of scanning electron microscopy (SEM) images acquired from fractured surfaces of tensile tested specimens. The nanocomposites produced could find a variety of applications such as; 3D-printed organic thermoelectric materials for plausible large-scale thermal energy harvesting applications, resistors for flexible circuitry, and piezoresistive sensors for strain sensing.

A gas migration law study of a large-scale 3D physical similarity simulation with an adaptive Kalman filter algorithm

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yuyu Hao ◽  
Shugang Li ◽  
Tianjun Zhang
Keyword(s):  
Kalman Filter ◽  
Large Scale ◽  
Gas Migration ◽  
Adaptive Kalman Filter ◽  
Physical Similarity ◽  
Content Type ◽  
Gas Concentration ◽  
Rock Formation ◽  
Concentration Estimation ◽  
Migration Law

Purpose In this study, a physical similarity simulation plays a significant role in the study of crack evolution and the gas migration mechanism. A sensor is deployed inside a comparable artificial rock formation to assure the accuracy of the experiment results. During the building of the simulated rock formation, a huge volume of acidic gas is released, causing numerous sensor measurement mistakes. Additionally, the gas concentration estimation approach is subject to uncertainty because of the complex rock formation environment. As a result, the purpose of this study is to introduce an adaptive Kalman filter approach to reduce observation noise, increase the accuracy of the gas concentration estimation model and, finally, determine the gas migration law. Design/methodology/approach First, based on the process of gas floatation-diffusion and seepage, the gas migration model is established according to Fick’s second law, and a simplified modeling method using diffusion flux instead of gas concentration is presented. Second, an adaptive Kalman filter algorithm is introduced to establish a gas concentration estimation model, taking into account the model uncertainty and the unknown measurement noise. Finally, according to a large-scale physical similarity simulation platform, a thorough experiment about gas migration is carried out to extract gas concentration variation data with certain ventilation techniques and to create a gas chart of the time-changing trend. Findings This approach is used to determine the changing process of gas distribution for a certain ventilation mode. The results match the rock fissure distribution condition derived from the microseismic monitoring data, proving the effectiveness of the approach. Originality/value For the first time in large-scale three-dimensional physical similarity simulations, the adaptive Kalman filter data processing method based on the inverse Wishart probability density function is used to solve the problem of an inaccurate process and measurement noise, laying the groundwork for studying the gas migration law and determining the gas migration mechanism.

Inlet Skew and the Growth of Secondary Losses and Vorticity in a Turbine Cascade

1989 ◽  
Author(s):  
J. A. Walsh ◽  
D. G. Gregory-Smith
Keyword(s):  
Experimental Investigation ◽  
Large Scale ◽  
Transverse Velocity ◽  
Axial Flow ◽  
Turbine Cascade ◽  
Streamwise Vorticity ◽  
Loss Prediction

This paper presents results of an experimental investigation into the effects of inlet skew on the flowfield of a large scale axial flow turbine cascade. The results are presented in terms of the development of the streamwise vorticity since, in classical terms, the streamwise vorticity generates the transverse velocity components that cause the generation of the secondary losses. Inlet skew is shown to have a profound effect on the distribution and magnitude of the generated losses. A number of correlations for the secondary losses are compared with the measured values and it is shown that the correlations are not adequate for accurate loss prediction purposes.

scholarly journals Large-scale experimental investigation of the installation of suction caissons in silt sand

2016 ◽  
Vol 60 ◽  
pp. 109-120 ◽  
Author(s):  
Fei Chen ◽  
Jijian Lian ◽  
Haijun Wang ◽  
Fang Liu ◽  
Hongzhen Wang ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Large Scale ◽  
Suction Caissons

scholarly journals Large-scale 3D printing with cable-driven parallel robots

2017 ◽  
Vol 1 (1-4) ◽  
pp. 69-76 ◽  
Author(s):  
Jean-Baptiste Izard ◽  
Alexandre Dubor ◽  
Pierre-Elie Hervé ◽  
Edouard Cabay ◽  
David Culla ◽  
...  
Keyword(s):  
3D Printing ◽  
Large Scale ◽  
Parallel Robots

Experimental investigation of a large-scale paste-cooled MHD channel

2000 ◽  
Vol 38 (4) ◽  
pp. 643-649
Author(s):  
N. M. Sergeenko ◽  
A. G. Blokh ◽  
A. V. Pisakin ◽  
B. G. Tkachenko ◽  
V. A. Zeigarnik ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Large Scale ◽  
Mhd Channel

Step Ring Based 3D Path Planning via GPU Simulation for Subtractive 3D Printing

2016 ◽  
Author(s):  
Zhengkai Wu ◽  
Thomas M. Tucker ◽  
Chandra Nath ◽  
Thomas R. Kurfess ◽  
Richard W. Vuduc
Keyword(s):  
3D Printing ◽  
Path Planning ◽  
Large Scale ◽  
Cnc Machining ◽  
Scale Model ◽  
Material Surface ◽  
Processing Unit ◽  
Cad Model ◽  
Set Partition ◽  
Central Processing

In this paper, both software model visualization with path simulation and associated machining product are produced based on the step ring based 3-axis path planning to demo model-driven graphics processing unit (GPU) feature in tool path planning and 3D image model classification by GPU simulation. Subtractive 3D printing (i.e., 3D machining) is represented as integration between 3D printing modeling and CNC machining via GPU simulated software. Path planning is applied through material surface removal visualization in high resolution and 3D path simulation via ring selective path planning based on accessibility of path through pattern selection. First, the step ring selects critical features to reconstruct computer aided design (CAD) design model as STL (stereolithography) voxel, and then local optimization is attained within interested ring area for time and energy saving of GPU volume generation as compared to global all automatic path planning with longer latency. The reconstructed CAD model comes from an original sample (GATech buzz) with 2D image information. CAD model for optimization and validation is adopted to sustain manufacturing reproduction based on system simulation feedback. To avoid collision with the produced path from retraction path, we pick adaptive ring path generation and prediction in each planning iteration, which may also minimize material removal. Moreover, we did partition analysis and g-code optimization for large scale model and high density volume data. Image classification and grid analysis based on adaptive 3D tree depth are proposed for multi-level set partition of the model to define no cutting zones. After that, accessibility map is computed based on accessibility space for rotational angular space of path orientation to compare step ring based pass planning verses global all path planning. Feature analysis via central processing unit (CPU) or GPU processor for GPU map computation contributes to high performance computing and cloud computing potential through parallel computing application of subtractive 3D printing in the future.

scholarly journals From Line to Loop, A Circular 3D Printing Initiative for Upcycling Commercial Fishing Plastics

2021 ◽  
Author(s):  
◽  
Matthew O'Hagan
Keyword(s):  
3D Printing ◽  
Large Scale ◽  
Commercial Fishing ◽  
Fishing Gear ◽  
Fishing Industry ◽  
Distributed Manufacturing ◽  
Research Through Design ◽  
Management Scheme ◽  
The Pacific ◽  
Manufacturing Technologies

<p>The current linear use of plastic products follows a take, make and waste process. Commonly used by large scale industries, including the commercial fishing industry, this process results in approximately 8 million tonnes of plastic entering the ocean every year. While the fishing industry supplies livelihoods, a valuable food source and financial capital to millions of people worldwide, it’s also a significant contributor to the ocean plastics crisis. Without effective recycling schemes, an estimated 640,000 tonnes of plastic fishing gear is abandoned, lost or discarded within the ocean every year. New Zealand is no exception to this problem, as China’s waste import ban, as well as a lack of local recycling infrastructures, has resulted in the country’s commercial fishing gear polluting local coastlines as well as islands in the pacific. With the only other option for the plastic fishing gear being landfill, there is a critical need for circular initiatives that upcycle used plastic fishing gear locally into eco-innovative designs.  This research examines the issue by investigating how used buoys, aquaculture ropes and fishing nets from New Zealand’s fishing company ‘Sanford’ may be upcycled into eco-innovative designs through distributed manufacturing technologies. It introduces the idea of the circular economy, where plastic fishing gear can be reused within a technical cycle and explores how 3D printing could be part of the solution as it provides local initiatives, low material and energy usage and customisation. Overall, the research follows the research through design based on design criteria approach. Where materials, designs and systems are created under the refined research criteria, to ensure the plastic fishing gear samples are upcycled effectively into eco-innovative designs through 3D printing.  The tangible outputs of this research demonstrate how a circular upcycling system that uses distributed manufacturing technologies can create eco-innovative designs and provide a responsible disposal scheme for plastic fishing gear. It provides a new and more sustainable waste management scheme that could be applied to a range of plastic waste streams and diverts materials from entering the environment by continuously reusing them within the economy.</p>

Sign in / Sign up

Export Citation Format

Share Document