Interactive analysis of cavity-flows in a virtual environment

Abstract

Multiple everyday life situations involve cavity flows. Because of its unstable aspect, this phenomenon represents an issue of the utmost seriousness for physicists. This paper describes the design of a system dedicated to interactive analysis of results of CFD (Computational Fluid Dynamics) simulations. This approach aims at assisting expert users in their analysis in a virtual immersive environment. The proposed solution counts two main steps. In the first one, while moving a 3D cursor, the user explores the space of the simulation in order to locate potential areas of interest. During this exploration, for each position of the cursor, the flowlines starting from the vicinity of this position are rendered in real time. Based on his/her expertise, the user has to decide which areas may present a particular interest for the geometry (morphology) of the flow. Each area selected in the first step is examined in detail in the second step. During this second step a single flowline (detailing the variation of the flow velocity) starting from the position selected by the user is rendered. This step helps at clarifying, analyzing in detail, a characteristic sensed by the intermediate of the first step. Here, instead of an algorithm, the expert user has to decide whether the rendered flowline is relevant or not for the construction of the geometry of the flow. All the flowlines selected by the user are the elements that constitute the geometry of the studied flow.

A Systematic Literature Review of User Evaluation in Immersive Analytics

“…For displaying the course of objects or particles as well as spatial movement, trajectories were found in 23/231 of the analysed studies. In this category, we also include flowlines, which were used to visualise the airflow in a cavity [Men12].…”

Data-Driven Sonification of CFD Aneurysm Models

“…Menelas [16] provides a technique for interactively assessing open-cavity flow phenomena using virtual reality (VR) techniques. With an emphasis on visual feedback, Menelas attempts to address the complexity related to the analysis of CFD data using visual, haptic, and audio feedback.…”

“…Although the current research began independently of the work of Klein and Staadt, Kasakevich, and Menelas [14,15,16], it has converged upon a similar solution in which high-density data sonification is navigated within a three-dimensional auditory field with a focus on the communication of spatiotemporal data. The design of the current work benefited from Klein and Staadts observations regarding sample volume sizing; a balance must be struck between providing a granular representation of a single point or a cacophonous representation of a large volume.…”

“…The motivation for the current work was to address the shortcomings of data visualization with respect to temporal fluctuations, whereas previous works sought to address the visual clutter associated with high-dimensional datasets. The works of Klein and Staadt, Kasakevich, and Menelas directly communicate time domain values, such as velocity of flow, in order to reduce the strain on visual bandwidth by mapping magnitude of vectors directly to amplitude or filter cutoff [14,15,16]. For those previous works, this is suitable, allowing the user to directly query the data and receive auditory feedback proportional to the measured data.…”

Use of Haptics to Promote Learning Outcomes in Serious Games

“…Vision is perfect for the comparison of the spatial arrangement of objects, whereas haptics are at least as good as sight for the discrimination of textures [24]. It thus appears that solutions based only on one of the visual channels do not take advantage of the multi-sensory capabilities of humans [25,26].…”