Papers by Keyword: Visualization

Abstract: Mathematical modeling for 3D bioprinting allows us to avoid widespread errors and also time and financial losses. It is necessary for such critical processes as tissue spheroids fusion and diffusion of nutrients in them. The reason is that tissue spheroids fusion is the base of the 3D bioprinting technology. In this work, we propose an approach for tissue spheroids fusion modeling considering a need to compromise between fidelity of the geometric form and viability of the whole bioconstruct.

Abstract: Visualization experiments are performed to examine the role of acoustic cavitation bubbles that appear in 0.43-MHz ultrasonic water flow spreading over glass surfaces in the context of physical cleaning. The cleaning performance is evaluated using glass samples on which small silica particles are spin-coated. The visualization suggests that acoustic cavitation bubbles play a major role in particle removal as in the case of conventional cleaning with ultrasonic cleaning baths.

Abstract: Significant research is being conducted in the simulation of fluid flows due to the increase in employing the physics of the fluid flow to either commercial, in-house or open source codes. The analysis of the fluid flow is mainly based on the Lagrangian or the Eulerian approach. Many of the simulation codes employ the Eulerian approach due to its simplicity. These codes are based on several numerical techniques and yet few benchmarks have been conducted. However, the codes which employ the Lagrangian approach seem to be promising and may accurately simulate fluid flow phenomena. In this paper, a comparative analysis of the Lagrangian and Eulerian approach is investigated for a water droplet in a tank. The velocity field and the total pressure of the fluid are generated for the simulation by employing Ansys Fluent for the Eulerian approach and DualPhysics for the Lagrangian approach. The fluid structure and the fluid flow development are compared in order to assess the capability of each approaches in analysing the investigated fluid flow. This study may play a significant role on the importance of employing the Lagrangian approach for fluid flows where complex fluid structure occurs.

Abstract: Cold gas dynamic spray (CGDS) is a solid-state material additive manufacturing method where the particulate feedstock is accelerated under high pressure and relatively low temperature to supersonic condition to develop thin coatings or 3D freeform objects. In this paper, a literature review of the CGDS state-of-art, explanation of fundamentals of gas dynamic principles required to generate supersonic flow condition, and demonstration of a flow model based on computational flow dynamics (CFD) are presented. The focus of the preliminary 3D CFD model validation is the demonstration aerodynamics structures such as shocks that appear in the CGDS problem.

Abstract: In this study, the authors evaluated pressure distribution on a backing plate in friction-stir processing (FSP) utilizing an embedded pressure pin connected to a load sensor. They conducted FSP on aluminum alloy plates repeatedly offsetting the path-lines from the center of the pin and recorded change of forming pressure with tool position, which was compiled from the bearing load of the pin. The authors mapped the results to visualize the two-dimensional contact pressure distribution on a backing plate during FSP. They then compared the height distribution of the wall fabricated by friction-stir forming (FSF) utilizing a die having a groove with the observed distribution of pressure. Consequently, maximum pressure was observed beneath the rim of the tool probe at the retreating side (RS), and the highest points of the wall were observed at the RS.

Abstract: Visualization of work surface topography through simulations is very challenging task in grinding process due to the complexity of wheel-work interactions with a very high number of cutting points (grits). Kinematic mapping of abrasive grits on a three-dimensional wheel topography enables the evaluation of ground surface topography through simulations. In this paper, a method for generating the ground surface topography based on wheel specifications is presented. Abrasive grits size, abrasives volume percentage and their nature of distribution on the wheel surface are considered in the modeling and visualization of wheel topography. The simulation results of ground surface topographies prove the feasibility of the developed method.

Abstract: With the growth of computing technologies including both hardware and simulation algorithms, simulation models have become extremely large in scale. Nowadays the visualization of the huge result data obtained by the large scale simulation is one of the main bottlenecks through all the simulation procedures because such large scale simulation is generally conducted on computing servers such as supercomputers, while the visualization is done on local client environments. To avoid time consuming transfer of the result data from the computing server to the local client, we propose techniques for the server-side screening and network visualization of them in advance to their transfer. We demonstrate that our approach contributes to find out the region of interests in whole the result data by a numerical example.

Abstract: Heat pipe is well known device which is used to heat transfer phase-change of working fluid. Pulsating heat pipe (PHP) is special type of heat pipe which heat transfer by pulsating movement of working fluid. Article deals about operating activity and thermal performance measurement of this special heat pipe. Operating activity visualization of PHP was performed with PHP made from glass. The two types of PHPs were made. The first PHP has internal diameter of tube 1 mm, second PHP has internal diameter of tube 1.5 mm and both PHPs have eleven meanders. The working fluids used in PHP were water and Fluorinert FC-72. These fluids were chose for their different thermo-physical properties and the visualization observe formation of liquid and vapour phase working fluid during filling process and working operation.Next, the article describes thermal performance measurement of PHP depending on working fluid amount and heat source temperature. Measurement was performed with PHP made from copper tube with inner diameter 1.5 mm curved to the twenty one meanders and filled with water. The results give us image about formation and distribution of working fluid in pulsating heat pipe and about influence of working fluid amount on the heat transfer ability of pulsating heat pipe.

Abstract: The new MatPlus software supports the multi-dimensional modelling of materials properties using different data sources. Extensive mathematical functions allow curve fitting of data from different sources to any constitutive models and selectively combining models and datapoints along different dimensions. Physically consistent extrapolation of measured data within the complete multi-dimensional parametric space can be achieved. An integrated library of models can be extended by the user and already contains many popular equations like Hensel-Spittel and Zerilli-Armstrong for flow curves.

Abstract: The rules and capabilities of macro-strains identification method with the use of optical interference for identifying initial phase of plastic deformation process in steels with material instability were discussed in the work. It was also shown how the technique run in presentation of the initial phase of yielding progress. As the example for illustration of discussed method real capabilities the course of plastic deformations beginning in the tension tests of 15CrMo and 34CrNiMo6 steel samples was shown as well as the course of test of pure and simple bending for the steel 15CrMo beam. Namely, the sequence of interference fringes pictures showing the formation of plastic strains correlating to the points on the tensile test curve was presented. For bending process the pictures were correlated with the point on the graph of dimensionless bending moment versus maximal strain measured by the strain gauge