Regrasping behavior generation for rectangular solid object

Parallelized numerical modeling of the interaction of a solid object with immiscible incompressible two-phase fluid flow

Engineering Computations ◽

10.1108/ec-01-2016-0016 ◽

2017 ◽

Vol 34 (3) ◽

pp. 709-724 ◽

Cited By ~ 4

Author(s):

Amirmahdi Ghasemi ◽

R. Nikbakhti ◽

Amirreza Ghasemi ◽

Faraz Hedayati ◽

Amir Malvandi

Keyword(s):

Level Set ◽

Stokes Equations ◽

Density Ratio ◽

High Density ◽

Immersed Boundary ◽

Immersed Boundary Methods ◽

Solid Object ◽

Computational Tool ◽

Two Phase ◽

Content Type

Purpose A numerical method is developed to capture the interaction of solid object with two-phase flow with high density ratios. The current computational tool would be the first step of accurate modeling of wave energy converters in which the immense energy of the ocean can be extracted at low cost. Design/methodology/approach The full two-dimensional Navier–Stokes equations are discretized on a regular structured grid, and the two-step projection method along with multi-processing (OpenMP) is used to efficiently solve the flow equations. The level set and the immersed boundary methods are used to capture the free surface of a fluid and a solid object, respectively. The full two-dimensional Navier–Stokes equations are solved on a regular structured grid to resolve the flow field. Level set and immersed boundary methods are used to capture the free surface of liquid and solid object, respectively. A proper contact angle between the solid object and the fluid is used to enhance the accuracy of the advection of the mass and momentum of the fluids in three-phase cells. Findings The computational tool is verified based on numerical and experimental data with two scenarios: a cylinder falling into a rectangular domain due to gravity and a dam breaking in the presence of a fixed obstacle. In the former validation simulation, the accuracy of the immersed boundary method is verified. However, the accuracy of the level set method while the computational tool can model the high-density ratio is confirmed in the dam-breaking simulation. The results obtained from the current method are in good agreement with experimental data and other numerical studies. Practical/implications The computational tool is capable of being parallelized to reduce the computational cost; therefore, an OpenMP is used to solve the flow equations. Its application is seen in the following: wind energy conversion, interaction of solid object such as wind turbine with water waves, etc. Originality/value A high efficient CFD approach method is introduced to capture the interaction of solid object with a two-phase flow where they have high-density ratio. The current method has the ability to efficiently be parallelized.

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Spatial illumination vectors in interior lighting space with a solid object using Monte Carlo Simulation

JOURNAL OF THE ILLUMINATING ENGINEERING INSTITUTE OF JAPAN ◽

10.2150/jieij1980.80.appendix_130 ◽

1996 ◽

Vol 80 (Appendix) ◽

pp. 130-130

Author(s):

Terumi Takehara ◽

Masayoshi Nagata ◽

Naoyuki Shimomura

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Solid Object ◽

Interior Lighting

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The Development of an Automatic Three-Dimensional Mesh Generator via Modified Ray Casting

ASME 1992 International Computers in Engineering Conference: Volume 1 — Artificial Intelligence; Expert Systems; CAD/CAM/CAE; Computers in Fluid Mechanics/Thermal Systems ◽

10.1115/cie1992-0023 ◽

1992 ◽

Author(s):

Cengiz Yeker ◽

Ibrahim Zeid

Keyword(s):

Finite Elements ◽

Cell Structure ◽

Three Dimensional ◽

Ray Casting ◽

Solid Object ◽

Casting Technique ◽

Element Size ◽

A Cell ◽

Conforming Meshes ◽

Representation Scheme

Abstract A fully automatic three-dimensional mesh generation method is developed by modifying the well-known ray casting technique. The method is capable of meshing objects modeled using the CSG representation scheme. The input to the method consists of solid geometry information, and mesh attributes such as element size. The method starts by casting rays in 3D space to classify the empty and full parts of the solid. This information is then used to create a cell structure that closely models the solid object. The next step is to further process the cell structure to make it more succinct, so that the cells close to the boundary of the solid object can model the topology with enough fidelity. Moreover, neighborhood relations between cells in the structure are developed and implemented. These relations help produce better conforming meshes. Each cell in the cell structure is identified with respect to a set of pre-defined types of cells. After the identification process, a normalization process is developed and applied to the cell structure in order to ensure that the finite elements generated from each cell conform to each other and to other elements produced from neighboring cells. The last step is to mesh each cell in the structure with valid finite elements.

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Preliminary Study on Cutting Solid Object Using Water at Pressure Exceeding 1000 MPa

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.488-489.372 ◽

2012 ◽

Vol 488-489 ◽

pp. 372-376

Author(s):

Ahmad Humaizi Hilmi ◽

Norazman Mohamad Nor ◽

Ariffin Ismail ◽

Mohamed Yusof Alias ◽

Zi Jun Zhao ◽

...

Keyword(s):

Stainless Steel ◽

Pure Water ◽

Cutting Speed ◽

Solid Object ◽

Ultra High Pressure ◽

Solid Objects ◽

Stainless Steel 304 ◽

Optimum Geometry ◽

Preliminary Study ◽

Pump Pressure

To date, the highest pump pressure available in market is 648 MPa from FLOW International Corp. Cutting with ultra high pressure reduces abrasive usage, faster cutting speed, increased depth of cuts and increase efficiency. This research explores the possibility of applying pressure exceeding 1000 MPa to push pure water to cut solid objects. 10 grams of PE4 explosives are exploded in a confined chamber with a rectangular opening. Simulations in designing the blast test jig are discussed. Simulations are done using Autodyn software. The simulation aims to get the optimum geometry that can give the highest pressure at nozzle exit. Two materials are chosen to cut; stainless steel 304 and aluminum 1100. Simulations show the optimum blast test jig can cut aluminum and stainless steel at certain thickness.

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Letters to the Editor

PEDIATRICS ◽

10.1542/peds.52.3.464 ◽

1973 ◽

Vol 52 (3) ◽

pp. 464-464

Author(s):

Howard C. Mofenson

Keyword(s):

Solid Object ◽

Sudden Stop ◽

Letters To The Editor ◽

Crash Protection ◽

Child’S Weight

Each year 1,000 children under the age of 5 are killed riding in automobiles and another 60,000 suffer disabling injuries. Crash protection does not mean holding a child on the lap of the parent. If an automobile strikes a solid object or comes to a sudden stop the unrestrained passenger continues forward at the rate of speed of the car until stopped by a surface within the vehicle or ejected through the windshield. The geometric increase of the child's weight would not allow the parent's arms to restrain the child.

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Complexity Analysis in Additive Manufacturing for the Production of Tissue Engineering Constructs

Advances in Business Information Systems and Analytics - Analytical Approaches to Strategic Decision-Making ◽

10.4018/978-1-4666-5958-2.ch012 ◽

2014 ◽

pp. 240-257

Author(s):

Kouroush Jenab ◽

Philip D. Weinsier

Keyword(s):

Tissue Engineering ◽

Additive Manufacturing ◽

Human Tissue ◽

Complexity Analysis ◽

Three Dimensional ◽

Solid Object ◽

Tissue Replacement ◽

3D Solid ◽

Process Complexity ◽

Am Processes

Additive Manufacturing (AM) is a process of making a Three-Dimensional (3D) solid object of virtually any shape from a digital model that is used for both prototyping and distributed manufacturing with applications in many fields, such as dental and medical industries and biotech (human tissue replacement). AM refers to technologies that create objects through a sequential layering process. AM processes have several primary areas of complexity that may not be measured precisely, due to uncertain situations. Therefore, this chapter reports an analytical model for evaluating process complexity that takes into account uncertain situations and additive manufacturing process technologies. The model is able to rank AM processes based on their relative complexities. An illustrative example for several processes is demonstrated in order to present the application of the model.

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Complexity Analysis in Additive Manufacturing for the Production of Tissue Engineering Constructs

Additive Manufacturing ◽

10.4018/978-1-5225-9624-0.ch016 ◽

2020 ◽

pp. 370-393

Author(s):

Kouroush Jenab ◽

Philip D. Weinsier

Keyword(s):

Tissue Engineering ◽

Additive Manufacturing ◽

Human Tissue ◽

Complexity Analysis ◽

Three Dimensional ◽

Solid Object ◽

Tissue Replacement ◽

3D Solid ◽

Process Complexity ◽

Am Processes

Additive Manufacturing (AM) is a process of making a Three-Dimensional (3D) solid object of virtually any shape from a digital model that is used for both prototyping and distributed manufacturing with applications in many fields, such as dental and medical industries and biotech (human tissue replacement). AM refers to technologies that create objects through a sequential layering process. AM processes have several primary areas of complexity that may not be measured precisely, due to uncertain situations. Therefore, this chapter reports an analytical model for evaluating process complexity that takes into account uncertain situations and additive manufacturing process technologies. The model is able to rank AM processes based on their relative complexities. An illustrative example for several processes is demonstrated in order to present the application of the model.

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Noninvasive acoustic manipulation of objects in a living body

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2001779117 ◽

2020 ◽

Vol 117 (29) ◽

pp. 16848-16855 ◽

Cited By ~ 6

Author(s):

Mohamed A. Ghanem ◽

Adam D. Maxwell ◽

Yak-Nam Wang ◽

Bryan W. Cunitz ◽

Vera A. Khokhlova ◽

...

Keyword(s):

Numerical Modeling ◽

Human Body ◽

Kidney Stone ◽

Phased Array ◽

Bladder Wall ◽

Medical Applications ◽

Solid Object ◽

Living Body ◽

Glass Spheres ◽

Solid Objects

In certain medical applications, transmitting an ultrasound beam through the skin to manipulate a solid object within the human body would be beneficial. Such applications include, for example, controlling an ingestible camera or expelling a kidney stone. In this paper, ultrasound beams of specific shapes were designed by numerical modeling and produced using a phased array. These beams were shown to levitate and electronically steer solid objects (3-mm-diameter glass spheres), along preprogrammed paths, in a water bath, and in the urinary bladders of live pigs. Deviation from the intended path was on average <10%. No injury was found on the bladder wall or intervening tissue.

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