Tuesday, April 24, 2012

Setup Complete Aircraft for Analysis in About One Minute

Often it is necessary to analyze a complete airplane to determine loads, moments and stability (with and without stores, gears and external tanks) for various flight configurations.

Stallion 3D is a unique MS Windows software that simplifies this task by importing a CAD model that represents the geometry of interest and then automatically perform the necessary computing to generate the aerodynamics information.

Stallion 3D uses an novel formulation of the immersed boundary method, IBM, (based on a 3D Cartesian grid) to automatically detect immersed geometries and perform grid refinement at the boundaries.  Hanley's original ghost-cells based boundary scheme is automatic and can even work with near-zero-thickness surfaces to model sails and other aerodynamic structures.

The following video shows how to input the full 3D aircraft for analysis in Stallion 3D. Given a .stl (from NASA VSP, for example) the setup time is about one minute. Please click the following link to view the video:

More information about Stallion 3D can be found at: http://www.hanleyinnovations.com/stallion3d.html

Do not hesitate to contact us at (352) 240-3658 for more information.

BTW, here are a few recent pictures from Stallion 3D.  In some images, the geometries are from TurboSquid.com. Other geometries were created using Stallion's built-in wing editor.

Meteor at Mach 10.  Picture shows the temperature field.

Cartesian grid for joined-wing (box wing) model.

Sailboat simulation demostrating the ability to analyze thin surfaces.

Building and trees in the wind (steady flow).

Thanks for reading and best regards.

Wednesday, April 11, 2012

NASA Vehicle Sketch Pad

NASA's  Vehicle Sketch Pad (VSP) was released in January 2012 as an open source program.  VSP is an easy-to-use CAD software package dedicated to the rapid design of 3-dimensional solid models of airplanes, UAVs and other aircraft types.  More information about VSP (OpenVSP) and links to download a free copy can be found at the following page: http://www.openvsp.org.  The following video demonstrates the ease of use of VSP:

Additional tutorial information can be found at the following link:  http://www.openvsp.org/vid_tutorial.html

VSP exports to a variety of formats including .stl files.  This allows you to export your solid model for additive manufacturing or analysis in Stallion 3D and  other CAE programs:

Vehicle Sketch Pad and Stallion 3D (or similar program) are ideal tools for rapid aerodynamics conceptual design and analysis of aircraft.  Stallion 3D  can import the aircraft geometry in a single step using the .STL import function under the Design menu:

It's easy to import a STL file from VSP into Stallion 3D

Once the aircraft is imported in Stallion 3D, it will generate a grid and analyze the aircraft with a single click.  The user can also select the speed and other parameter for the aircraft.  In the following case for the Boeing 747-400, the speed is 290 meters/second and the angle of attack is 5 degrees:

This analysis shows the surface pressure and the Cp at various span locations.

Once you design and analyze one vehicle in VSP and Stallion 3D, it is hard to stop.  The following pictures show the pressure on the surface of two of the other complete aircraft that comes with VSP:

Pressure on surface of Cirrus aircraft included in VSP.

Pressure on the surface of  Cessna aircraft included in VSP

In short, NASA Vehicle Sketch Pad is a fun program to download and design aircraft.  It is even more fun to use Stallion 3D to analyze the aircraft and test the design in a digital wind tunnel.

More information can be found at http://www.hanleyinnovations.com/stallion3d.html
What is your favorite tools for rapid design and analysis?

Do not hesitate to email or call me at (352) 240-3658 if you have any questions. Thanks for reading and best wishes.  Patrick.