scholarly journals Visualization of Post-Processed CFD Data in a Virtual Environment

1999 ◽  
Author(s):  
Vishant J. Shahnawaz ◽  
Judy M. Vance ◽  
Sasikumar V. Kutti
Keyword(s):  
Virtual Reality ◽  
Fluid Flow ◽  
Flow Field ◽  
Vector Fields ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Scalar Fields ◽  
Grid Data ◽  
Head Mounted Display ◽  
Graphical Environment

Abstract This paper discusses the development of a virtual reality (VR) interface for the visualization of Computational Fluid Dynamics (CFD) data. The application, VR-CFD, provides an immersive and interactive graphical environment in which users can examine the analysis results from a CFD analysis of a flow field in three-dimensional space. It has been tested and implemented with virtual reality devices such as the C2, head mounted display (HMD) and desktop VR. The application is designed to read PLOT3D structured grid data and to display the flow field parameters using features such as streamlines, cutting planes, iso-surfaces, rakes, vector fields and scalar fields. Visualization Toolkit (VTK), a data visualization library, is used along with OpenGL arid the C2 VR interface libraries, to develop the application. Analysts and designers have used VR-CFD to visualize and understand complex three-dimensional fluid flow phenomena. The combination of three-dimensional interaction capability and the C2 virtual reality environment has been shown to facilitate collaborative discussions between analysts and engineers concerning the appropriateness of the CFD model and the characteristics of the fluid flow.

scholarly journals How Can I Grab That?

i-com ◽  
2020 ◽  
Vol 19 (2) ◽  
pp. 67-85
Author(s):  
Matthias Weise ◽  
Raphael Zender ◽  
Ulrike Lucke
Keyword(s):  
Virtual Reality ◽  
User Experience ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Advantages And Disadvantages ◽  
Multiple Dimensions ◽  
Application Developers ◽  
Three Dimensional Space

AbstractThe selection and manipulation of objects in Virtual Reality face application developers with a substantial challenge as they need to ensure a seamless interaction in three-dimensional space. Assessing the advantages and disadvantages of selection and manipulation techniques in specific scenarios and regarding usability and user experience is a mandatory task to find suitable forms of interaction. In this article, we take a look at the most common issues arising in the interaction with objects in VR. We present a taxonomy allowing the classification of techniques regarding multiple dimensions. The issues are then associated with these dimensions. Furthermore, we analyze the results of a study comparing multiple selection techniques and present a tool allowing developers of VR applications to search for appropriate selection and manipulation techniques and to get scenario dependent suggestions based on the data of the executed study.

scholarly journals Optimization Design of a 2.5 Stage Highly Loaded Axial Compressor with a Bezier Surface Modeling Method

2020 ◽  
Vol 10 (11) ◽  
pp. 3860
Author(s):  
Song Huang ◽  
Jinxin Cheng ◽  
Chengwu Yang ◽  
Chuangxin Zhou ◽  
Shengfeng Zhao ◽  
...  
Keyword(s):  
Flow Field ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Axial Compressor ◽  
High Dimensions ◽  
Peak Efficiency ◽  
Stall Margin ◽  
Second Stage ◽  
Highly Loaded ◽  
Three Dimensional Space

Due to the complexity of the internal flow field of compressors, the aerodynamic design and optimization of a highly loaded axial compressor with high performance still have three problems, which are rich engineering design experience, high dimensions, and time-consuming calculations. To overcome these three problems, this paper takes an engineering-designed 2.5-stage highly loaded axial flow compressor as an example to introduce the design process and the adopted design philosophies. Then, this paper verifies the numerical method of computational fluid dynamics. A new Bezier surface modeling method for the entire suction surface and pressure surface of blades is developed, and the multi-island genetic algorithm is directly used for further optimization. Only 32 optimization variables are used to optimize the rotors and stators of the compressor, which greatly overcome the problem of high dimensions, time-consuming calculations, and smooth blade surfaces. After optimization, compared with the original compressor, the peak efficiency is still improved by 0.12%, and the stall margin is increased by 2.69%. The increase in peak efficiency is mainly due to the rotors. Compared with the original compressor, for the second-stage rotor, the adiabatic efficiency is improved by about 0.4%, which is mainly due to the decreases of total pressure losses in the range of above 30% of the span height and 10%–30% of the chord length. Besides, for the original compressor, due to deterioration of the flow field near the tip region of the second-stage stator, the large low-speed region eventually evolves from corner separation into corner stall with three-dimensional space spiral backflow. For the optimized compressor, the main reason for the increased stall margin is that the flow field of the second-stage stator with a span height above 50% is improved, and the separation area and three-dimensional space spiral backflow are reduced.

A Permutation Technique for the Spatial Analysis of the Distribution of Artifacts into Classes

1980 ◽  
Vol 45 (1) ◽  
pp. 55-59 ◽  
Author(s):  
Kenneth J. Berry ◽  
Kenneth L. Kvamme ◽  
Paul W. Mielke
Keyword(s):  
Spatial Analysis ◽  
Permutation Test ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Exact Method ◽  
Grid Data ◽  
Permutation Technique ◽  
A Site ◽  
Three Dimensional Space

A permutation test for assessing intrasite patterning of artifact distributions in archaeological space is presented. This test requires none of the usual assumptions about the data; permits either exact locational or counts/grid data in one-, two-, or three-dimensional space; and provides an exact method for testing any hypothesis concerning the nonrandom allocation of artifacts into classes within a site.

scholarly journals Overview: Virtual Reality in Medicine

2014 ◽  
Vol 7 (1) ◽  
Author(s):  
Claudio Pensieri ◽  
Maddalena Pennacchini
Keyword(s):  
Virtual Reality ◽  
Second Life ◽  
Surgical Simulation ◽  
3D Visualization ◽  
Economic Value ◽  
Three Dimensional ◽  
Communication Interface ◽  
Head Mounted Display ◽  
Wide Range ◽  
Interactive 3D

Background: Virtual Reality (VR) was defined as a collection of technological devices: “a computer capable of interactive 3D visualization, a head-mounted display and data gloves equipped with one or more position trackers”. Today, lots of scientists define VR as a simulation of the real world based on computer graphics, a three dimensional world in which communities of real people interact, create content, items and services, producing real economic value through e-Commerce.Objective: To report the results of a systematic review of articles and reviews published about the theme: “Virtual Reality in Medicine”.Methods: We used the search query string: “Virtual Reality”, “Metaverse”, “Second Life”, “Virtual World”, “Virtual Life” in order to find out how many articles were written about these themes. For the “Meta-review” we used only “Virtual Reality” AND “Review”. We searched the following databases: Psycinfo, Journal of Medical Internet Research, Isiknowledge till September 2011 and Pubmed till February 2012. We included any source published in either print format or on the Internet, available in all languages, and containing texts that define or attempt to define VR in explicit terms.Results: We retrieved 3,443 articles on Pubmed in 2012 and 8,237 on Isiknowledge in 2011. This large number of articles covered a wide range of themes, but showed no clear consensus about VR. We identified 4 general uses of VR in Medicine, and searched for the existing reviews about them. We found 364 reviews in 2011, although only 197 were pertinent to our aims: 1. Communication Interface (11 Reviews); 2. Medical Education (49 reviews); 3. Surgical Simulation (49 Reviews) and 4. Psychotherapy (88 Reviews).Conclusion: We found a large number of articles, but no clear consensus about the meaning of the term VR in Medicine. We found numerous articles published on these topics and many of them have been reviewed. We decided to group these reviews in 4 areas in order to provide a systematic overview of the subject matter, and to enable those interested to learn more about these particular topics.

The Research on Architecture Design Engineering Method Based on Computer Virtual Reality Technology

2012 ◽  
Vol 487 ◽  
pp. 568-570
Author(s):  
Zhi Yi Mao
Keyword(s):  
Virtual Reality ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Building Design ◽  
Image Synthesis ◽  
Design Quality ◽  
Virtual Reality Technology ◽  
Improve Design ◽  
Design Cycle ◽  
Three Dimensional Space

Also known as virtual reality or virtual reality environments virtual environment, is rapidly developing a comprehensive computer and interactive graphics technology, which integrates computer graphics, multimedia, artificial intelligence, multi-sensor, network parallel processing, the use of computer-generated three-dimensional space image synthesis technology to achieve the goal, through visual, hearing, touch, in order to render the graphics and animation, the viewer, "seeing is bright." Virtual reality technology is an integrated building design approach, designed to reduce labor intensity, shorten the design cycle, improve design quality, saving investment. Designers to design the building and engineering units can communicate with each other on the World Wide Web.

A Computational Model for the Stereoscopic Optics of a Head-Mounted Display

1992 ◽  
Vol 1 (1) ◽  
pp. 45-62 ◽  
Author(s):  
Warren Robinett ◽  
Jannick P. Rolland
Keyword(s):  
Virtual Reality ◽  
Computational Model ◽  
Relative Position ◽  
Three Dimensional ◽  
Model Parameters ◽  
Head Mounted Display ◽  
Interpupillary Distance ◽  
Modeling Errors ◽  
Physical Geometry ◽  
Physical Objects

For stereoscopic photography or telepresence, orthostereoscopy occurs when the perceived size, shape, and relative position of objects in the three-dimensional scene being viewed match those of the physical objects in front of the camera. In virtual reality, the simulated scene has no physical counterpart, so orthostereoscopy must be defined in this case as constancy, as the head moves around, of the perceived size, shape, and relative positions of the simulated objects. Achieving this constancy requires that the computational model used to generate the graphics matches the physical geometry of the head-mounted display being used. This geometry includes the optics used to image the displays and the placement of the displays with respect to the eyes. The model may fail to match the geometry because model parameters are difficult to measure accurately, or because the model itself is in error. Two common modeling errors are ignoring the distortion caused by the optics and ignoring the variation in interpupillary distance across different users. A computational model for the geometry of a head-mounted display is presented, and the parameters of this model for the VPL EyePhone are calculated.

Laminar Fluid Flow around Two Wall-Mounted Cubes of Arbitrary Configuration

2010 ◽  
Vol 224 (11) ◽  
pp. 2396-2407 ◽  
Author(s):  
M Eslami ◽  
M M Tavakol ◽  
E Goshtasbirad
Keyword(s):  
Fluid Flow ◽  
Flow Field ◽  
Free Stream ◽  
Three Dimensional ◽  
Bluff Bodies ◽  
Vortical Structures ◽  
Laminar Fluid Flow ◽  
Pressure Distributions ◽  
Arbitrary Configuration ◽  
Computational Fluid Dynamics Cfd

The problem of flow field around multiple bluff bodies mounted on a surface is of great significance in different fields of engineering. In this study, a computational fluid dynamics (CFD) code is developed to calculate three-dimensional (3D) steady state laminar fluid flow around two cuboids of arbitrary size and configuration mounted on a surface in free stream conditions. This study presents the results for two cubes of the same size mounted on a surface in both inline and staggered arrangements. Streamlines are plotted for various combinations of the distance between the two cubes and Reynolds number. Moreover, the effects of different parameters on vortical structures, separation, and reattachment points are discussed. Also, velocity and pressure distributions are plotted in the wake region behind the two cubes. It is clearly shown that how the presence of the second cube changes the flow field and the vortical structures in comparison with the case of a single cube.

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