Change search
ReferencesLink to record
Permanent link

Direct link
Virtual-reality environment for visualization of unsteady three-dimensional CFD data
KTH, Superseded Departments, Aeronautical and Vehicle Engineering.
KTH, Superseded Departments, Aeronautical and Vehicle Engineering.
2004 (English)In: ECCOMAS 2004 - European Congress on Computational Methods in Applied Sciences and Engineering, 2004, 1-20 p.Conference paper (Refereed)
Abstract [en]

A Virtual-Reality (VR) environment has been set up to visualize, explore and interact with steady and time-dependent three-dimensional CFD solutions in a fully immersive way. The paper presents the VR system and provides some examples of currently investigated applications in the area of computational aerodynamics, such as the unsteady flow over a full-span delta wing at high angle of attack, the steady hypersonic flow around an atmospheric reentry vehicle and the steady airflow around a human female standing in a strong headwind. These pre-computed three-dimensional flows have been visualized interactively in a six-sided CAVE, demonstrating that the sheer sensual impact of the immersive display has a powerful effect on the physical intuition. Several user can move around freely in the VR environment, without being distracted from the flow to be investigated by the analytical tools and menus. The users have a common experience and can discuss the visualized flow field while interacting with it. Our experience with using VR for visualizing, exploring and analyzing complex unsteady three-dimensional CFD data are summarized and benefits and limitations are highlighted.

Place, publisher, year, edition, pages
2004. 1-20 p.
Keyword [en]
Virtual reality, CAVE, unsteady aerodynamics, CFD, visualization, delta wing, vortex breakdown
National Category
Engineering and Technology
URN: urn:nbn:se:kth:diva-4924ScopusID: 2-s2.0-84893519295OAI: diva2:7054
European Congress on Computational Methods in Applied Sciences and Engineering, ECCOMAS 2004; Jyvaskyla; Finland; 24 July 2004 through 28 July 2004

QC 20101018

Available from: 2005-02-11 Created: 2005-02-11 Last updated: 2014-04-23Bibliographically approved
In thesis
1. Realistic simulations of delta wing aerodynamics using novel CFD methods
Open this publication in new window or tab >>Realistic simulations of delta wing aerodynamics using novel CFD methods
2005 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

The overall goal of the research presented in this thesis is to extend the physical understanding of the unsteady external aerodynamics associated with highly maneuverable delta-wing aircraft by using and developing novel, more efficient computational fluid dynamics (CFD) tools. More specific, the main purpose is to simulate and better understand the basic fluid phenomena, such as vortex breakdown, that limit the performance of delta-wing aircraft. The problem is approached by going from the most simple aircraft configuration - a pure delta wing - to more complex configurations. As the flow computations of delta wings at high angle of attack have a variety of unusual aspects that make accurate predictions challenging, best practices for the CFD codes used are developed and documented so as to raise their technology readiness level when applied to this class of flows.

Initially, emphasis is put on subsonic steady-state CFD simulations of stand-alone delta wings to keep the phenomenon of vortex breakdown as clean as possible. For half-span models it is established that the essential characteristics of vortex breakdown are captured by a structured CFD code. The influence of viscosity on vortex breakdown is studied and numerical results for the aerodynamic coefficients, the surface pressure distribution and breakdown locations are compared to experimental data where possible.

In a second step, structured grid generation issues, numerical aspects of the simulation of this nonlinear type of flow and the interaction of a forebody with a delta wing are explored.

Then, on an increasing level of complexity, time-accurate numerical studies are performed to resolve the unsteady flow field over half and full-span, stationary delta wings at high angle of attack. Both Euler and Detached Eddy Simulations (DES) are performed to predict the streamwise oscillations of the vortex breakdown location about some mean position, asymmetry in the breakdown location due to the interaction between the left and right vortices, as well as the rotation of the spiral structure downstream of breakdown in a time-accurate manner. The computed flow-field solutions are visualized and analyzed in a virtual-reality environment.

Ultimately, steady-state and time-dependent simulations of a full-scale fighter-type aircraft configuration in steady flight are performed using the advanced turbulence models and the detached-eddy simulation capability of an edge-based, unstructured flow solver. The computed results are compared to flight-test data.

The thesis also addresses algorithmic efficiency and presents a novel implicit-explicit algorithm, the Recursive Projection Method (RPM), for computations of both steady and unsteady flows. It is demonstrated that RPM can accelerate such computations by up to 2.5 times.

Place, publisher, year, edition, pages
Stockholm: KTH, 2005. ix, 68 p.
Trita-AVE, ISSN 1651-7660 ; 2005:01
Space and plasma physics, CFD, aerodynamics, flow physics, steady, unsteady, delta wing, vortical flow, Rymd- och plasmafysik
National Category
Fusion, Plasma and Space Physics
urn:nbn:se:kth:diva-125 (URN)91-7283-938-4 (ISBN)
Public defence
2005-02-15, Kollegiesalen, Valhallavägen 79, Stockholm, 10:15
QC 20101019Available from: 2005-02-11 Created: 2005-02-11 Last updated: 2010-10-19Bibliographically approved

Open Access in DiVA

No full text

Other links

ScopusECCOMAS 2004

Search in DiVA

By author/editor
Görtz, StefanSundström, Elias
By organisation
Aeronautical and Vehicle Engineering
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 192 hits
ReferencesLink to record
Permanent link

Direct link