Tuesday, August 5, 2014

Onera M6 Wing Revisited

Stallion 3D uses an automatic Cartesian grid to provide the best accuracy and computational efficiency when compared to the topology of other grids.  The grid is automatically generation and the process is invisible to the user during the workflow.

Stallion 3D offers users the option to create simulation sizes ranging form quick (about 60,000 cells) to detailed (about 2,00,000 cells).   The Quick run allows users to preview how well a geometry performs before committing to a larger flow model size.  The results below were obtain from two different simulation sizes.  The first one is about 440,000 cells and is referred to as the coarse grid in the graphs.  The second model is about 1,600,000 cells and is referred to the fine grid.

A drop down box allows user to select the size of the simulation.

Stallion 3D accepts 3D solid models in the .stl format.  The stl file reader allows users to scale, rotate and position the model in the flow field.  The stl file of the Onera M6 wing  for this example is obtained from NASA OpenVSP.

The simulation parameters are setup with the well know case of M=0.84 and an angle of attack of 3.06 degrees.  The result below shows the pressure on the surface of the wing for the fine grid case.

Analysis of Onera M6 Wing. V=288 m/s. Angle of Attack = 3.06 degrees


Cp at the 20% span location. 

Cp at the 44% span location.


Cp at the 65% span location.


Cp at the 90% span location.

Cp at th 95% span location.

Stallion 3D compute forces and coefficients by integrating the pressure at the surface.  This often provides good results for the lift and pressure drag.  Caution must be taken when using this option if the model consists of a small number of facets or the geometry has a significant number of inwardly facing facets normal.

Stallion 3D Forces integrated on the geometry (Facets)
    
No. Cells
          CL          CD (Pressure)
Coarse Grid
440,000
0.268
0.0178
Fine Grid
1,600,000
0.275
0.0155
CFL 3D**
N/A
0.266
0.0172 (total)
Results Table for Faceted Surface Force Integration.

Another option for finding the forces (especially when the geometry is questionable) is to use the Cartesian front option.  This is a boundary consisting of the outward faces of the Cartesian cells closest to the geometry.  To find the forces, the momentum equation is evaluated on the cell faces (Cartesian Front).  This method provides good results for fine grids.  In any case, the results for both methods of force integration should agree with each other.

Forces integrated on the Cartesian Front (Momentum Equation)
    
No. Cells
          CL        
CD (Pressure)
Coarse Grid
440,000
0.273
0.0124
Fine Grid
1,600,000
0.278
0.0112
CFL 3D**
N/A
0.266
0.0172 (total)
Results Table for Cartesian Front Force Integration

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

Related Article:
Onera M6 Wing, Star of CFD, http://www.onera.fr/en/actualites/image-du-mois/onera-m6-wing-star-cfd

 CFL 3D Viscous Calculations: http://cfl3d.larc.nasa.gov/Cfl3dv6/cfl3dv6_testcases.html#onera **

Do not hesitate to email or telephone us at (352) 240-3658 if you have any questions.
Thanks for reading.

Saturday, July 26, 2014

Stepping Up Your Aerodynamics Conceptual Analysis

At Hanley Innovations, we develop software tools that enables you to easily transform your ideas into actual flying prototypes.  One way to get your idea to work is to start with a concept about which you are quite certain, I mean really, really confident (an airfoil, for example), and then, like the Science Channel suggest, you Build It Bigger.

VisualFoil Enables You to Clarify Airfoil Concepts Before
Moving On to the Next Step. Airfoil Analysis Starts at $29

With a family of airfoils in hand (because no one can fly in 2-dimensions), the concept steps up to a wing (because birds have them and .... they can fly very well).  The next simple step is to extrude your airfoil (s) into a 3-D surface to support your weight at various flight speeds.  What is soon realized is that other surfaces of various shapes, sizes & orientation (which use your original airfoil concepts) are need to help balance your design in flight (stability). Stability depends in part on weight distribution (center of gravity) over the entire (what we can now call) airplane with respect to the neutral point (similar to aerodynamic center) location.

3DFoil Can Be Used to Design  Multiple Wings
and Workout Weight and Stability Issues.

For most people, trial by 3DFoil, results in concepts which you print, template and fly.  But what if, just what if you still want to Build it Even Bigger.  Stallion 3D can be used to take concepts even further.  The program can actually read-in your project files from 3DFoil and further the analysis of your concept. The video shows how Stallion 3d imports and analyzes a kite that was created in 3DFoil or MultiSurface Aerodynamics.

Stallion 3D will Read-In MultiSurface Aero/3DFoil Files for Detailed 3D Analysis

The next time your have a BIG idea, do not hesitate to visit Hanley Innovations to Build It Even Bigger.


The Aerodynamics Class Pack combines airfoil, wing and the Stallion 3D software and the modules can be accessed your entire class on their individual PC over the course of one year.

You may also call us at (352) 240-3658.

Thanks for reading.

Monday, July 21, 2014

Hanley Innovations initiates Just-In-Time Pricing for CFD

Hanley Innovations initiates Just-In-Time Pricing for CFD with $295 per month for Stallion 3D with HIST.


Invariably, pricing-out engineering software for a project becomes a distressing scenario. Concrete conditions on lengths of lease times for software packages are frequently either too long or too short for particular projects. Compounding the issue is the task of piecing together separate integrated software packages and the inescapable hours and days of wrangling grids and points onto a surface.

In response, Hanley Innovations has initiated Just-In-Time Pricing for CFD to further our commitment to facilitate a company’s or school’s lean manufacturing practices. Stallion 3D contains the novel algorithm HIST (Hanley Innovations Surface Treatment) which reduces your workflow to seconds. The program features fully automatic invisible gridding and Navier-Stokes and Euler solvers that handles viscous flows on complex arbitrary geometries on your laptop.

Stallion 3D effortlessly handles a CAD file size of 100,000 facets on a 64-bit computer. In ONE day with Stallion 3D with HIST, you will be able to purchase, set-up, and get a full 2.5 million analysis run. Full technical support is offered throughout the entire time of your lease
.
About Stallion 3D
Stallion 3D with HIST is a fully automatic, All-In-One, software package for analyzing 3D complex geometries in fluid flows (gas or liquid). The software allows you to perform aerodynamics analysis on just your laptop or desktop computer. It employs a novel computational fluid dynamics (CFD) technique HIST that solves the fluid equations and produces plots of pressure, velocity, Mach number and temperature. The software also computes the lift, drag moments and related forces acting on your 3D CAD geometry.

More information about Stallion 3D can be found at http://www.hanleyinnovations.com/stallion3d.html or by calling (352) 240-3658.

Monday, July 7, 2014

What is Stallion 3D with HIST - exactly?

What is Stallion 3D with HIST?
Stallion 3D is a fully automatic, All-In-One, software package for analyzing 3D complex geometries in  fluid flows (gas or liquid).  The software allows you to perform aerodynamics analysis  on just your laptop or desktop computer.  It employs a novel computational fluid dynamics (CFD) technique that solves the fluid equations and produces plots of pressure, velocity, Mach number and temperature. The software also computes the lift, drag moments and related forces acting on your 3D CAD geometry.

Analysis of Porsche using Stallion 3D. CAD file obtained from grabcad.com

What is HIST?
HIST is the acronym for Hanley Innovations Boundary Treatment. It is a propriety CFD technique that applies the flow boundary conditions to arbitrary geometries immersed in a Cartesian Grid. HIST can handle both inviscid and viscous (no-slip) boundary conditions.  It can be used to solve subsonic, transonic and supersonic flow problems.

Stallion 3D Solution of Laminar Flow over a Tapered Wing.

Why is the program referred to as an “All-In-One”?
Stallion 3D does not require the purchase of additional software for pre- and post processing. . It handles everything from reading in a CAD model to graphing and tabulating the results of your aerodynamics/CFD analysis.

Is HIST similar to other grandfather or newer CFD solvers on the market freeware?
The HIST solver is entirely new and robust enough to capture shock waves and analyze viscous flows.

Is Stallion 3D with HIST,  an interface software,  to use with pre-existing Cartesian software program?
It is not an interface program. It is an All-in-One aerodynamics & CFD program for analyzing CAD geometries in a flow field.


How long does it take for someone to setup a problem for analysis in Stallion 3D? 
Setting-up,  literally, takes.... just seconds. 


Do I have to mesh a grid at any time?
Stallion 3D specifically eliminates the need for our customers to grid because of HIST, our invisible meshing feature.

Do I need to purchase a pre-processor or mesh generating software for  Stallion 3D?
No. Grid generation is built into Stallion 3D.

Do I need to purchase a separate solver to analyze the geometry?
No. It is built-in already in Stallion 3D. Stallion 3D is equipped with algorithms to solve the full 3D compressible Euler & Navier-Stokes equations.  The analysis is valid for low and high speed flows of liquids and gasses.

Laminar flow analysis over a golf ball using Stallion 3D.

Do I need to purchase post processing or separate graphic package to see the graphics after the simulation is finished?
No.  It is built-in already in Stallion 3D.

What are the workflow steps for Stallion 3D? 
1. Insert watertight CAD picture. (takes just a few seconds)
2. Add your parameters (Flow speed, angle of attack, ground effect or rotation  take just a few moments to specify in Stallion 3D.)
3. Stallion 3D will fully and accurately mesh and set-up your grid and begin the analysis.
4. Once the flow is analyzed, the program will automatically have your results ready for you to view or save.

Analysis of rotor blade (also from grabcad.com) with quasi-steady rotation. Stallion 3D 
performs gridding, computations and post processing for complex 3D geometries.

Hardware Requirements?
Laptop running the 64 bit version of Windows XP, 7 or 8 (8.1).

Does the program use a cloud to run simulations?
We do not use a cloud for running simulations. You can do all of your work on your laptop.

What is the general maximum number of cells that can be run for a Windows  simulation?
2.5 million cells.

What are the current prices for Stalllion 3D with HIST as of July 2014?
Please visit http://www.hanleyinnovations.com/stallion3d.html for current prices.

How soon do I receive the Stallion 3D after ordering?
The same day.  Please call us at (352) 240-3658 or visit http://www.hanleyinnovations.com to place your orders.

If I purchase the popular 3 month lease subscription, can I apply what paid for the 3 month lease to a 12 month lease?
You can upgrade to  a 12 month lease, with the 3 month credit.

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

Thanks for reading.

Saturday, June 28, 2014

An Overview of CFD Vision Goals for 2030

But....really...why wait?

Five CFD 2030 Wish-List Ideas Currently Available at Hanley Innovations

Wish 1.) A Revolutionary Algorithm. 
It is universally agreed, that a new algorithm is essential to handle the increasing complexity of geometries presented for analysis in today's engineering arena.

Hanley Innovations Surface Treatment (HIST) is the propriety algorithm developed to respond to the uncompromising demands of your research.

Analysis of the DLR F11 High Lift Configuration on a HP Pavilion dv6

With HIST powering Stallion 3D, you can perform serious external CFD on your laptop at work or home.

HIST handles complex CAD geometries, subsonic, transonic and supersonic regimes and viscous (no-slip) boundary conditions.

Wish 2.)  Seamless Integration.
Today's standard CFD workflow process for analyzing an object requires expert juggling of several different software packages. Stallion 3D with HIST is seamless and is the only 3D program that completely sets-up... in seconds.

Stallion 3D with HIST eliminates the need for you to learn how to mesh and overlay grids, pay for extra software, and spend days in training just to get your work completed on time.

Wish 3.) Invisible Meshing
Everyone understands why CFDers need invisible meshing in their CFD program.

Stallion 3D's invisible meshing capabilities, affords the CFD community the opportunity to focus on other aspects of their workload and research, rather than taking hours and subsequent days setting-up a CAD geometry.

Stallion 3D Cartesian Grid at a Station Along the Span of the DLR F11 

Stallion 3D with HIST is genuinely invisible, and most importantly, our results correspond to validation wind tunnel testing runs from NASA, so there is no stress in wondering about the accuracy of your results derived from our program.
Undoubtedly, Stallion 3D is the easiest CFD program on the market.

You never again have to overlay additional grid shapes, add points, subtract areas, build-up bumps, eye-ball, or cross your fingers to increase accuracy when generating your mesh.

 Wish 4.) High Powered Computers
Admittedly, all the mention of future computing hardware possibilities, mentioned in the 2030 AIAA presentation was enough to make anyone drool.

Today, though our children may not be impressed with computers, us over 50 years old, personally know how far hardware has progressed beautifully .

Stallion 3D with HIST  allows you to do serious calculations on your laptop. An average set-up of 2 million cells can be completely loaded into the program

Wish 5.) Organized Data Collection
Once your simulation has finished your simulation, all the pertinent results are automatically tabulated for you.

References

1. Slotnick,Jeffrey, et. al., "CFD Vision 2030 Study: A Path to Revolutionary Computational Aerosciences",  http://ntrs.nasa.gov/search.jsp?R=20140003093

2. 2nd AIAA CFD High Lift Prediction Workshop, http://hiliftpw.larc.nasa.gov/

3. 3D CFD simulation performed using Stallion 3D. Please visit http://www.hanleyinnovations.com/stallion3d.html. Prices start at $890.

More Information

Please visit http://www.hanleyinnovations.com or telephone (352) 240-3658 for more information.
Thanks for reading.

Sunday, April 27, 2014

Supersonic Aerodynamics

Years ago, the X-15 was an experimental aircraft for testing futuristic supersonic and hypersonic space plane concepts such as the space shuttle orbiter.

I used Stallion 3D to do a quick comparison of an X-15 CAD model at  two flight Mach numbers, M=3.5 and M=6.0.  The model of the X-15 was taken from NASA OpenVSP hanger.  The results are shown below:

    X-15:  In the top picture M=3.5.  The Mach number is 6.0 in the picture at the bottom.

The following link has a very interesting article on the X-15 aerodynamics:  http://history.nasa.gov/SP-60/ch-5.html.  If you are interested in developing airplane concepts, NASA OpenVSP is a good option.  More information can be found at http://www.openvsp.org.

The .stl output of OpenVSP can be read directly in Stallion 3D for rapid aerodynamics analysis (no external grid generation).  More information can be found at http://www.hanleyinnovations.com.

Do not hesitate to email or telephone me at (352) 240-3658 if you have any questions. Thanks for reading.

Wednesday, December 11, 2013

Through 180-Degree Angle of Attack

Following the 1981 paper,  "Aerodynamic Characteristics of Seven Symmetrical Airfoil Sections Through 180 Degree Angle of Attack for Use in Aerodynamic Analysis of Vertical Axis Wind Turbines", Sand80, by Robert E. Sheldahl, et. al., I analyzed the NACA 0012 in MultiElement Airfoils at various angles past stall.

The following picture shows the results of the analysis superimposed on a graphs from the Sandia study.

Analysis of a NACA 0012 airfoil through 180 degrees angle of attack.
The blue dots are the Navier-Stokes solution in MultiElement Airfoils.
  The red Xs are the potentialflow/boundary layer solution.

For the analysis, I used the laminar Navier-Stokes solution setting in MultiElement Airfoils.  The software is based on a Cartesian grid methods (ghost cell approach for the boundary conditions) and has a variety of flow solvers.   The following picture shows the flow at 5 degrees angle of attack.

Analysis of NACA 0012 in MultiElement Airfoils 5.1

More information about MultiElement Airfoils can be found at http://www.hanleyinnovations.com/mefoil.html

Thanks for reading.