## To Use Large Deflection or Not, That Is the Question

It seems like I’ve been explaining large deflection effects a lot recently. Between co-teaching an engineering class at nearby Arizona State University and also having a couple of customer issues regarding the concept, large deflection in structural analyses has been on my mind.

Before I explain any further, the thing you should note if you are an ANSYS Mechanical simulation user is this: If you don’t know if you need large deflection or not, you should turn it on. There is really no way to know for certain if it’s needed or not unless you perform a comparison study with and without it.

So, what are large deflection effects? In simple terms the inclusion of large deflection means that ANSYS accounts for changes in stiffness due to changes in shape of the parts you are simulating. The classic case to consider is the loaded fishing rod.

In its undeflected state, the fishing rod is very flexible at the tip. With a heavy fish on the end of the line, the rod deflects downward and it is then easy to observe that the stiffness of the rod has increased. In other words, when the rod is lightly loaded, a small amount of force will cause a certain downward deflection at the top. When the rod is heavily loaded however, a much larger amount of force will be needed to cause the tip to deflect downward by the same amount.

This change in the force amount required to achieve the same change in displacement implies that we do not have a linear relationship between force and displacement.
Consider Hooke’s law, also known as the spring equation:

F = Kx

Where F is the force applied, K is the stiffness of the structure, and x is the deflection. In a linear system, doubling the force results in double the displacement. In our fishing rod case, though, we have a nonlinear system. We might need to triple the force to double the displacement, depending on how much the rod is loaded relative to its size and other properties, and then to double the displacement again we might need to apply four times that force, just using numbers out of my head as examples.

So, in the case of the fishing rod, Hooke’s law in a linear form does not apply. In order to capture the nonlinear effect we need a way for the stiffness to change as the shape of the rod changes. In our finite element solution in ANSYS, it means that we want to recalculate the stiffness as the structure deflects.

This recalculation of the stiffness as the structure deflects is activated by turning on large deflection effects. Without large deflection turned on, we are constrained to using the linear equation, and no matter how much the structure deflects we are still using the original stiffness.

So, why not just have large deflection on by default and use it all the time? My understanding is that since large deflection adds computation expense to have it on, it’s off by default. It’s the same as for a lot of advanced usage, such as frictionless or frictional contact vs. the default bonded (simpler) behavior. In other words, turning on large deflection will trigger a nonlinear solution, meaning multiple passes through the solver using the Newton Raphson method instead of the single pass needed for a linear problem.

Here is an example of a simplified fishing rod. The image shows the undeflected rod (top), which is held fixed on the left side and has a downward force load applied on the right end. The bottom image shows the final deflected shape, with large deflection effects included. The deflection at the tip in this case is 34 inches.

In comparison running the same load with large deflection turned off resulted in a tip deflection of 40 inches. Thus, the calculated tip deflection is 15% less with large deflection turned on, since we are now accounting for change in stiffness with change in shape as the rod deflects.

Below we have a force (horizontal axis) vs. deflection (vertical axis) plot for a nonlinear simulation of a fishing rod with large deflection turned on. The fact that the curve is not a straight line confirms that this is a nonlinear problem, with the stiffness (slope of the curve) not constant. We can also see that as the force gets higher, the slope of the curve is more horizontal, meaning that more force is needed for each incremental amount of displacement. This matches our observations of the fishing rod behavior.

So, getting back to our original point, it’s often the case that we don’t know if we need to include large deflection effects or not. When in doubt, run cases with and without. If you don’t see a change in your key results, you can probably do without large deflection.

Here is an example using an idealized compressor vane. In this case, the deflections and stresses with and without large deflection effects are nearly the same (the stress difference is about 0.2%).

Large Deflection On:

Small Deflection:

Bottom line: when in doubt, try it out, with and without large deflection. In ANSYS Mechanical, Large Deflection effects are turned on or off in the details of the Analysis Settings branch.

It’s worth noting that turning on large deflection in ANSYS actually activates four different behaviors, known as large deflection which include large rotation, large strain, stress stiffening, and spin softening. All of these involve change in stiffness due to deformation in one way or another.

If you like this kind of info, or find it useful, we cover topics like this in our training classes. For more info, check out our training pages at http://www.padtinc.com/support/software/training.html.

## 3D Printing – A 2D Explainer from Shapeways

What is this 3D Printing anyway?  It doesn’t take long for someone new to the technology to see the wide range of applications and implications it brings to the table.  But what how does it actually work. Our friends at Shapeways have put together a great infographic that explains things well.

Take a look and share:

If you scrolled down this far, you may be asking, “Why is PADT sharing Shapeways material? Are they not competitors?”  Well, to be honest, we recommend Shapeways to people all the time. Our Additive Manufacturing business is about producing engineering prototypes, tooling, and end-use products for manufacturing companies. When a hobbiest or artist comes to ask us for a prototype, we often recommend that they go visit Shapeways.

We also recommend that people who are interested in all the non-engineering applications for 3D Printing check out their marketplace. The things that people have come up with is just amazing and shows the unbounded potential of this technology.

## Presentation: Leveraging Simulation for Product Development of IoT Devices

The local SEMI chapter here in Arizona held a breakfast meeting on Monetizing Internet of Things (IoT) and PADT was pleased to be one of the presenters. Always a smart group, this was a chance to sit with people making the sensors, chips, and software that enable the IoT and dig deep in to where things are and where they need to be.

The event was hosted by one of our favorite customers, and neighbor right across the street, Freescale Semiconductor.  Speakers included IoT experts from Freescale, Intel, Medtronics, ASU, and SEMICO Research.

Not surprisingly I talked about how Simulation can play a successful role in product development of IoT devices.

You can download a copy of the presentation here: PADT-SEMI-IOT-Simulation-1.pdf

UPDATE (11/9/2015): Great write-up by Don Dingee on this event in the SemiWiki. Click here to read it. It includes a great summary of the other speakers.

You can also see more details on how people use Simulation for this application on the ANSYS, Inc. website here.  We also like this video from ANSYS that shows some great applications and how ANSYS is used with them:

A couple of common themes resonated across the speakers:

1. Price and size need to come down on the chips used in IoT (this was a semiconductor group, so this is a big part of their focus)
2. Lowering power usage and increasing power density in batteries is a key driver
3. The biggest issue in IoT is privacy and security. Keeping your data private and keeping people from hacking in to IoT devices.
4. Another big problem is dealing with all the data collected by IoT devices. How to make it useful and how to store it all.  One answer is reducing the data on the device, another is only keeping track of what changes.
5. It is early, standards are needed but they are still forming.

If you look at this list, the first two problems are addressable with simulation:

PADT has a growing amount of experience with helping customers simulate and design IoT devices as well as the chips, sensors, and antenna that go in to IoT devices.  To learn more, shoot us an email at info@padtinc.com or call 480.813.4884.

## Manufacturing Open House Highlights – October 2015

Here at PADT we help people who make products, stuff that gets manufactured.  So we focused our open house yesterday on advanced manufacturing and invited the community to come out and network, learn, and share.  Even though it was a busy week for technology events in Arizona, we had a great turnout on a surprisingly cloudy Wednesday evening.

October is Manufacturing month and this open house was part of the Arizona Commerce Authority’s coordinated events to highlight manufacturing in Arizona.   You can learn more about other events in the state here.

This event was a bit more casual and less structured then past PADT open houses, letting attendees spend more time one-on-one with various experts and dig deep in to technologies like metal 3D Printing, urethane casting, topological optimization, and scanning.

What struck all of us here was the keen interest in and knowledge about the various tools we were showing across a wide range of attendees.  From students with home built 3D Printers to managers from local aerospace companies that are on the forefront of Additive Manufacturing, the questions that were asks and comments that were made with insightful and show a transition of this technology from hype to real world application.

Below are some more quick snapshot taken during the event.

A big thanks to everyone who made it out and we hope to see more of you next time. If you have any questions about the application of advanced manufacturing technologies to your products, don’t hesitate to reach out to us at info@padtinc.com or 480.813.4884.  As always, visit www.PADTINC.com to learn more.

## Free Training and Evaluation for ANSYS AIM

PADT is hosting a series of free training classes to introduce users to ANSYS AIM.  We have pasted the invitation below.  You can register here.  We are very excited about this new tool from ANSYS, Inc. and are eager to share it with everyone. Look for more AIM information on this blog in the near future.

## Free Training and Evaluation for ANSYS® AIM™. Register Today – Seats Are Limited.

Discover how to design your next product
better… and faster

## ANSYS AIM: Integrated Multiphysics Simulation Environment for All Engineers

### Free Training and Evaluation for ANSYS® AIM™ – An Integrated Multi-physics Simulation Environment for All Engineers

As a special offer, PADT Inc. is offering FREE “Jump Start” training and hands-on evaluation for ANSYS® AIM™. Design engineers, method engineers and managers seeking to learn the latest simulation software, boost adoption and usability for the occasional user, or extend their existing CAD-based tool’s limited functionality will benefit from this no-obligation course.

Register Today – Seats are limited and will be filled on a first-come, first-served basis. On completion of the class, you’ll be qualified to receive and use a FREE 30-day ANSYS AIM download for evaluation.

All classes will be held from 9:00 a.m. – 4:00 p.m. local time and include a complimentary lunch.

PADT’s support team of ANSYS experts will help attendees understand where ANSYS AIM fits in to their organization and workflow. The class will address both situations and how ANSYS AIM provides the integration of CAD based systems and the ease of use of a modern tool in a product that steps the occasional user through the process without limiting functionality.

Watch this short video to learn more about the capabilities and benefits of ANSYS® AIM™ for the simulation of 3-D physics and multiphysics

## Beyond the Hype – Additive Manufacturing and 3D Printing Worldwide, A Summary of Terry Wholers’ Thoughts

Terry Wholers is the founder and principal consultant of Wohlers Associates Inc., an independent consulting firm that was launched 28 years ago. Wohlers and his team have provided consulting work to over 240 organizations in 24 countries as well as to 150 companies in the investment community. He has authored over 400 books, articles, and technical papers. Terry has twice served as a presenter at the White House. For the past 20 years hes has been the principal author for the Wohlers Report which is an annual worldwide publication focused on Additive Manufacturing and 3D Printing. In 2007 more than a 1,000 industry professionals from around the world selected Terry as the most influential person in Rapid Prototyping Development and Additive Manufacturing.

PADT was fortunate enough to sponsor, with the local SME group, an event in Fort Collins, Colorado where Terry came and shared his views on the industry. What follows is a summary of what we learned. They are basically notes and observations.  Please contact us for any clarification or details:

Terry Wohlers started his talk by asking: How many people have heard of 3D printing?

He noted that these days it was pretty much everyone and if you haven’t then you must be living in a cave. It is like everyone can’t get enough of it.

There has been a lot of growth. In the last 5 years the industry has quadrupled. Last year it was a 4.1 billion industry and this year 5.5 billion. Terry doesn’t own any stock in any of the different 3D printing companies. He cautioned everyone to not confuse the share prices with the growth and the expansion within this industry.

After this introduction, Terry stated that there were really two things in the industry that really excited him.  3D Printing for Manufacturing and for Production Parts.

## 3D Printing in Manufacturing.

The first area to watch is the use of this technology for manufacturing applications. The team looking at the sales data drew a line in the sand for the low cost hobbyist printers at \$5,000. There were 140,000 of them sold last year compared to under 13,000 above \$5k. However, they don’t cost much so the money is still in the industrial machines. Here are the revenues for 2014:

Industrial: 1.12 Billion, or 86.6%.
Hobbyist: 173.3 Million, or 13.4%

There are FDM clones everywhere. 300 or more brands. There is a lot of open source software out there to develop your own FDM printer.

One thing to watch in the industry is expiring patents. This opens up competition and lowers prices and sometimes brings better machines to market.  Right now, the SLS patent expired in June of last year so we are seeing new Selective Laser Sintering devices coming to market.

An exciting example of using 3D printing in manufacturing is the landing gear created by Stratasys. It was built and assembled with a Stratasys FDM printer and used for a fit check. Very Cool!

In medical, some great examples of tooling are jigs, fixtures, drill press, and custom cutting guide for knee replacement. You can take scanned data and create a custom cutting guide for replacing your knee. Tens of thousands of those have been done.

Lots of work is being done on test fixtures as well.

In tooling, with additive manufacturing you can do things that are highly complex. Instead of just straight gun drilled cooling channels you can make the cooling channels conform to the purpose of the part. You can reduce 30-300% cycle time by improving the cooling channels for injection molding dies.  It turns out that Lego is printing their molds! They are using conformal cooling to increase their cycle times.

On the aerospace side of things, end use parts are literally taking off.  Airbus is flying today 45,000 to 60,000 Ultem plastic parts. Both passenger and non-passenger planes have Ultem parts on them.

## 3D Printing for Final Production Parts

The second area to watch is the next frontier, and that is what excites him. You can do structural ribs in 3D printed parts. You need to make sure there are places in your parts to remove the support material used if you are going to use structural ribs. Design is absolutely critical. When he was at Solidworks world in Orlando a few years ago, there was a 3D printed bird that was flapping its wings.

This is a part of that bird that was being flown.

Two weeks ago Terry did a four day course at NASA on Design for Additive Manufacturing. The importance of the subject now is that companies and organizations are paying a lot of money to host people to teach them how to design for additive manufacturing. It was a great learning experience and NASA has already signed up for a second course that is focused on metals. NASA 3D printed a turbopump with 45%fewer parts that runs at 90,000 rpm, and creates 2,000 hp. This turbopump manufactured with conventional methods costs \$220,000 for one, they can 3D print 2 of them in Inconel for \$20,000.

A big part of Design for Additive Manufacturing is using the correct thinking but also using the right tools. There is a lack of both. We are taught to design for the conventional method of manufacturing. Now we have to undo some of that and think, hey there can be a better way to design this part.

One of those ways is Topology Optimization (let mathematics decide where to place the support structure so there is a increased strength to weight ratio). Another is the use of lattice structure (mesh and cellular). Ever since the beginning of time, man would make parts out of a solid material. Well now you can have a thin skin and a lattice structure on the interior to produce something superior in some cases.

We need these kind of tools integrated into the different CAD software’s so that we can design better parts.  This bracket is flying on a Airbus. This cabinet bracket is made out of titanium and is flying on the A35 Airbus. It was designed for 2.3 tons and actually holds up to 12.5-14 tons depending on the test. Peter Zander at Airbus believes that in 2 years they will be printing 30 tons of metal per month!

GE Aviation is building fuel nozzles for the new leap engine. The new design is 25% lighter and five times more durable than the previous design that took 20 different parts to assemble to make one fuel nozzle. The will be printing 40,000 fuel nozzles per year.

Consumer Products:
It is going to be very big. Terry thinks this is going to be a sweet spot in the industry. Once example is this guitar called the Hive Bass. It is built out of Nylon and would cost you \$3,500. You can have a custom guitar made for that price.

There is a Belgium company that creates custom frames for eyewear.

There is also a lot of Jewelry available for consumers along with many other products.

For metal part production there are many steps needed to finish the part. About 9 steps that Terry counted so it can be a long process.

Myth: Additive Manufacturing is fast! Well that depends on Polymers versus Metals and the size and complexity of the parts. Airbus had one build that took 14 days to print with their metal printer! GE mentioned that they have to print the same part twice before they get it right because they will have to reorient the part or change the build parameters to get the best quality build possible.

According to some estimates the global manufacturing economy is in the range of \$13 trillion. If this technology were to penetrate 2% of it then that is over a quarter of a trillion dollars. 5% is approaching two thirds of a trillion!

Terry finished by asking: How many of you think this will be North of the 5% estimate?

We want to thank Terry for giving such an informative talk, and New Belgium Brewing for hosting. The networking afterwords was fantastic.

If you would like to stay up to date on 3D Printing, we recommend the Wohlers Report. It is our primary reference document here at PADT.

## NICE Desktop Cloud Visualization

In a previous post I argued that engineers do magic (read it here). And to help them do their magic better PADT Inc. introduced CoresOnDemand.com.

Among the magical skills engineers use in their daily awesomeness is their ability to bend the time fabric of the universe and perform tasks in almost impossible deadlines. It’s as if engineers work long hours and even work from home, while commuting and even at the coffee shop. Wait, is that what they actually do?

Among a myriad of tools that facilitate remote access and desktop redirection available, one stands out with distinction. NICE-Software developed a tool called Desktop Cloud Visualization (DCV for short). DCV has numerous advantages that we will get into shortly. The videos below give a general idea of what can be achieved with NICE-DCV.

Here is a video from the people at NICE:

And here is one of two PADT Employees using an iPhone to check their CFD results:

# Advantages of Nice-DCV

## Physical location of cluster/workstation or the engineers becomes irrelevant

Because engineers have fast, efficient and secure access to their workstations and clusters, they no longer need to be in the same office or on the same network segment to utilize the available compute resources. They can utilize NICE-DCV to create a fast, efficient and encrypted connection to their resources to submit, monitor and process results. The DCV clients are supported on Windows, Linux & IOS and even have a stand-alone Windows client that can be run on shared or public computers. In a recent live test, one of our engineers was travelling on a shuttle bus to a tiny ski town in Colorado, he was able to connect over the courtesy Wifi, check the status of his jobs and visualize some of the results.

## The need for a powerful laptop or remote workstation to enable offsite work is no longer the only solution

There is no need for offsite engineers lug around a giant laptop in order to efficiently launch and modify their designs or perform simulation runs. Users launch the DCV client, connect to their workstation or cluster and are immediately given access to their desktop. No need to copy files, borrow licenses or transfer data. Engineers don’t need to create copies of files and carry them around on the laptops or on external storage which is an unnecessary security risk.

## “If it ain’t broken don’t fix it!”

Every engineer uses ANSYS in his own special way. Some prefer the good old command line for everything even when a flashy GUI option is available. Others are comfortable using the Windows like GUI interface and would

## Opens the door for GUI-only users to utilize large cluster resources without a steep learning curve or specialized tools.

Nice-DCV makes the use of ANSYS on large HPC clusters within reach for everyone. Engineers can log into pre-configured environments with all of the variables needed for parallel ANSYS runs already defined. Users can use can have their favorite ANSYS software added to the desktop as shortcuts or system admins can write small scripts or programs that serve as an answer file for custom job scripts.

## From 0-60 in about…10 Minutes

For an engineer with the smallest amount of system administration skills it takes about 10 minutes to install the Nice-DCV server and launch the first connection. It’s surprisingly simple and straightforward on both the server and the client side. The benefits of Nice-DCV can be immediately realized in both simplified cluster administration and peace of mind for both the engineers and the system admins.

## PADT’s CoresOnDemand and Nice-DCV

The CoresOnDemand service that PADT introduced last year utilizes the Nice-DCV tool to simplify and enhance the user experience. If you are interested in a live demo on Nice-DCV or the CoresOnDemand environment contact us either by phone: 480-813-4884 or by email cod@padtinc.com. For more information please visit: CoresOnCemand.com

(Note: some of the social media posts had a typo in the title, that was my fault (Eric) not Ahmed’s…)

## ReBlog: An Insider’s View on 3D Printing in Aerospace

In all the hype and hoopla around 3D Printing there are teams around the world that are quietly making a difference in manufacturing – making real parts and figuring out the processes, testing, and protocols needed to realize the dream of additive manufacturing.  One such team is at Honeywell Aerospace, and we are proud to be one of their vendors.

They just published a great blog on where they are and what they have achieved and we recommend you give it a read. Very informative.

### An Insider’s View on 3D Printing in Aerospace

If you would like to learn how you can use this same technology to move your manufacturing process forward, fill out our simple form here, call us at 480.813.4884, or send an email to info@padtinc.com.

## Special Event: Beyond the Hype – Additive Manufacturing and 3D Printing Worldwide

We are pleased and honored to announce a special event that PADT is sponsoring with the Colorado Society of Manufacturing Engineers.  Terry Wholers, a leading voice in the additive manufacturing space, is giving a presentation on the current state of all things AM.  The event is being held at the world famous New Belgium Brewery in Fort Collins, Colorado on September 15, 2015.

## Additive Manufacturing and 3D Printing Worldwide

Cut through the hype and hear about real world applications for additive manufacturing and 3D printing:

• Where is the industry growth?
• Which types of polymers and metals are used in 3D printing?
• What are practical uses for the technology in the engineering environment?
• What are current industry implementations for AM/3D printing?
• How is it being implemented in industry today?
• What kind of parts can be manufactured for final products?
• How important is the design process?
• What are the most common myths and misconceptions?
• What does the future hold?

If your company is thinking about how to practically introduce AM into your design/workflow/manufacturing process, this presentation is for you. Ask questions, discuss business opportunities, and speak in depth about the future.

Mr. Wohlers will highlight recent developments and growth trends that point to where the industry is headed and what the future holds. New products and services are being introduced at an astounding rate. Mr. Wohlers will sort through the maze of choices and opportunities associated with the methods used for rapid product development and additive manufacturing (AM).

Here is the agenda:

4:00 – Brew Tour of New Belgium Brewery –Must RSVP– only 16 spots available!
5:00 – Packaging tour of New Belgium Brewery –Must RSVP– only 48 spots available!
5:30 – 6:30 – Meet, Greet and Network
6:30 – Light Dinner Buffet – Must RSVP for buffet and presentation
7:00 – Presentation by Mr. Terry Wohlers
8:00 – Networking (meet Terry)
9:00 – End of event

Reservations are accepted through Friday, September 11th, so please register now!
Cost of the event is \$20 but is FREE if you mention PADT when you register.

To register please email reservations@sme354.org or
call Chuck Otoupalik at 303-678-8414

Terry Wohlers, founder of Wohlers Associates, Inc., a 28-year old independent consulting firm. Wohlers and his team have provided consulting assistance to more than 240 organizations in 24 countries, as well as to 150+ companies in the investment community. He has authored 400 books, articles, and technical papers and has given 125 keynote presentations on five continents. Wohlers has twice served as a featured speaker at events held at the White House. He is a principal author of the Wohlers Report, the undisputed industry-leading study on additive manufacturing and 3D printing for 20 consecutive years.

Here is what industry experts have to say about Mr. Wohlers and his company’s industry report:

“Why waste time and money when you can get a worldwide overview of additive manufacturing from Wohlers Associates-experts that have focused on AM for 26 years. The Wohlers Report is worth every dollar.”

Peter Sander, Vice President, Airbus Germany

“Now in its 18th year of publication (that’s right all you 3-D printing arrivistes, this stuff has been around for a while), the annual report describes a healthy and growing market for 3-D printing equipment, services, materials and processes, albeit one where the value continues to accrue to industrial applications.”

Michael Copeland, Senior Editor, WIRED

“The amount of information in the report is almost overwhelming. I am awed by its depth and breadth. What’s more, the information is not available anywhere else. For example, we hear how China is changing, but few people fully understand the transformation that’s underway. The report gives insight and clarification on China and it covers the rest of the world with the same careful analysis. It also provides insight into new products and applications that you normally would not hear about, such as light-weight structures, nanomanufacturing, growing organs, gaming, and new types of protective gear. One of the secrets of your success is the extensive travel worldwide, coupled with the information you seek from experts globally. Thank you for making something so remarkable available each year.”

Boris Fritz, Northrop Grumman

“If you need to know anything about where this technology is today or where it is going tomorrow, Wohlers Report is your guide.”

Anthony J. Lockwood, former editorial director, Desktop Engineering

## Press Release: Southern California Expansion Grows PADT’s ANSYS Product Development Software Distribution Business

Palm trees and movie stars.  Endless beaches and deserts that fade to the horizon.  Aerospace companies, world class universities, med device developers, and toy manufacturers.  Oil, freeways, and big construction. Southern California. A place larger and more diverse than most countries in the world.  PADT has done work in the area since our first weeks in business. As our business continued to grow, our customers started asking when we were opening up a local office, but the time never seemed right. Until now.

PADT is pleased to announce that we will be loading furniture and computers in a truck and head on the I-10 to Torrance, California where we will open up a new office.  ANSYS, Inc. has expanded our sales territory to include small and medium sized new accounts in the Southern California area.  The focus of this new office will be building that business.

You can read the official details in the press release below, or the PDF here.  As usual, we want to share some more informal information with our blog readers.

The office will be started with an engineer and a salesperson who have been with us for a while, and another pair that we are hiring locally. This combination of company experience and local knowledge should get us going quickly. Over time, the plan is to grow the Torrance office, and add at least two more. Long term we would like to have between 3 and 10 employees per office in Southern California.

Our team will conduct training and seminars from this office and use it as a base to spread the word on simulation driven product development across Southern California. The initial focus for sales will be on small and medium sized businesses that are currently not using ANSYS products, that want to work with a technical sales and support team who can provide more than the software tool – customers who want a partner who can also help them apply the tools effectively. The dense hotbeds of engineering along the coast will be an obvious area of concentration. We also aim to represent the value of ANSYS products in less visited areas of the region, including the high deserts, “in-between” towns, and inland locations beyond LA, Orange County, and San Diego.

The good news is that we are not starting from scratch. This first office is right down the street from the California campus of PADT’s largest and oldest customer.  We also have over one hundred customers who have used PADT for simulation services, training, rapid prototyping, and product development, and we will be reaching out to them shortly to start building our local network even further.  And then, our new employees who we will hire locally will be contacting their network as well.

Before the end of the summer we hope to have a grand opening event, as well as several seminars that will continue through the end of the year. If you live in the area and want to be invited, visit here to register as someone who want to be on the California contact list.

This blog and social media will be used to post our progress. The entire sales and technical team is looking forward to meeting everyone in the area in the coming months.

If you have any questions or suggestions for us, please contact us.  Our standard number 480.813.4884 works for all of our offices.

Below is a copy of the press release, or you can view the “official” version here.

Press Release:

Southern California Expansion Grows PADT’s ANSYS Product Development Software Distribution Business

PADT opens Torrance office to provide consultant-focused ANSYS Product Sales and Support for small and medium sized engineering businesses in the region

Tempe, Ariz., August 24, 2015 —Phoenix Analysis & Design Technologies, Inc. (PADT) the Southwest’s largest provider of Numerical Simulation, Product Development, and 3D Printing services and products, today announced the addition of Southern California to its ANSYS, Inc. Product Sales and Support territory. PADT is a long time ANSYS Channel Partner who has built a reputation for outstanding technical abilities and customer support in Arizona, New Mexico, Colorado, Utah, and Nevada. The company is now taking the same customer focused approach to selling and supporting the world’s leading product development simulation tools from ANSYS to new customers in Southern California.

“We are honored by ANSYS’ trust in PADT and are eager to start working more closely with their team in Southern California,” said Bob Calvin, PADT’s manager of Simulation Sales. “We have been doing business in this area since PADT was founded 21 years ago. Expanding our offering to include ANSYS products and support is something that makes sense for users, ANSYS and PADT.”

Located in Torrance California, PADT’s new office will be staffed by two sales people and two application engineers.  Aggressive growth will follow.

“We selected Torrance for our new Southern California office because it’s centrally located, easily accessible and right down the street from the California campus of our largest customer,” said Ward Rand, co-owner, PADT. “Having staff with real world industry experience located nearby will strengthen our ability to drive our customer’s product development process, resulting in higher quality products, improved performance and lower costs.”

PADT will open additional offices across the Southern California region in the coming two years with the long term goal of three total offices with three to ten employees each.  The location of these offices, just like the initial Torrance facility, will be chosen to provide service where the demand is greatest.

The ANSYS Channel Partner program is unique in the industry because it allows customers the option to purchase software and support from ANSYS directly, or from highly technical local consulting companies like PADT. Since Southern California has not had an ANSYS Channel Partner for thirteen years, PADT’s engineering experience and ANSYS product expertise will be a tremendous help to small and medium sized companies seeking to discover the power of ANSYS products, and efficiently implement Simulation Driven Product Development (SDPD).

Events, both on-line and face-to-face, will be announced in the coming months to celebrate the arrival of PADT in the area. Those interested in following PADT’s progress, can subscribe to any of the company’s social media outlets, PADT California emails, or visit the new PADT California web page (www.padtinc.com/socal). Anyone needing immediate information can contact PADT at info@padtinc.com or call 480.813.4884.

About Phoenix Analysis and Design Technologies

Phoenix Analysis and Design Technologies, Inc. (PADT) is an engineering product and services company that focuses on helping customers who develop physical products by providing Numerical Simulation, Product Development, and Rapid Prototyping solutions. PADT’s worldwide reputation for technical excellence and experienced staff is based on its proven record of building long term win-win partnerships with vendors and customers. Since its establishment in 1994, companies have relied on PADT because “We Make Innovation Work.” With over 75 employees, PADT services customers from its headquarters at the Arizona State University Research Park in Tempe, Arizona, and from offices in Littleton, Colorado, Albuquerque, New Mexico, and Murray, Utah, as well as through staff members located around the country. More information on PADT can be found at http://www.PADTINC.com.

# # #

Company contact:
Eric Miller
480.813.4884

Media contact:
Linda Capcara
TechTHiNQ
480-229-7090
linda.capcara@techthinq.com

# Engineers Do Magic

In the world of simulation there are two facts of life. First, the deadline of “yesterday would be good” is not too uncommon. Funding deadlines, product roll-out dates, as well as unexpected project requirements are all reliable sources for last minute changes. Engineers are required to do quality work and deliver reliable results in limited time and resources. In essence perform sorcery.

Second, the size and complexity of models can vary wildly. Anything from fasteners and gaskets to complete systems or structures can be in the pipeline. Engineers can be looking at any combination of hundreds of variables that impact the resources required for a successful simulation.

Required CPU cores, RAM per core, interconnect speeds, available disk space, operating system and ANSYS version all vary depending on the model files, simulation type, size, run-time and target date for the results.

Engineers usually do magic. But sometimes limited time or resources that are out of reach can delay on-time delivery of project tasks.

# At PADT, We Can Help

PADT Inc. has been nostrils deep in engineering services and simulation products for over 20 years. We know engineering, we know how to simulate engineering and we know ANSYS very well. To address the challenges our customers are facing, in 2015 PADT introduced CoresOnDemand to the engineering community.

CoresOnDemand offers the combination of our proven CUBE cluster, ANSYS simulation tools and the PADT experience and support as an on demand simulation resource. By focusing on the specific needs of ANSYS users, CoresOnDemand was built to deliver performance and flexibility for the full range of applications. Specifics about the clusters and their configurations can be found at CoresOnDemand.com.

CoresOnDemand is a high performance computing environment purpose built to help customers address numerical simulation needs that require compute power that isn’t available or that is needed on a temporary basis.

# Call Us We’re Nice

CoresOnDemand is a new service in the world of on-demand computing. Prospective customers just need to give us a call or send us an inquiry here to get all of their questions answered. The engineers behind CoresOnDemand have a deep understanding of the ANSYS tools and distributed computing and are able to asses and properly size a compute environment that matches the needed resources.

Call us we’re nice!

# Two Halves of the Nutshell

The process for executing a lease on a CoresOnDemand cluster is quite straight forward. There are two parts to a lease:

## PART 1: How many cores & how long is the lease for?

By working with the PADT engineers – and possibly benchmarking their models – customers can set a realistic estimate on how many cores are required and how long their models need to run on the CoresOnDemand clusters. Normally, leases are in one-week blocks with incentives for longer or regular lease requirements.

Clusters are leased in one-week blocks, but we’re flexible.

## Part 2: How will ANSYS be licensed?

An ANSYS license is required in order to run on the CoresOnDemand environment.  A license lease can be generated by contacting any ANSYS channel partner. PADT can generate license leases in Arizona, Colorado, New Mexico, Utah & Nevada. Licenses can also be borrowed from the customer’s existing license pool.

An ANSYS license may be leased from an ANSYS channel partner or borrowed from customer’s existing license pool.

# Using the Cluster

Once the CoresOnDemand team has completed the cluster setup and user creation (takes a couple of hours for most cases), customers can login and begin using the cluster. The CoresOnDemand clusters allow customers to use the connection method they are comfortable with. All connections to CoresOnDemand are encrypted and are protected by a firewall and an isolated network environment.

## Step 1: Transfer files to the cluster:

Files can be transferred to the cluster using Secure Copy Protocol which creates an encrypted tunnel for copying files. A graphical tool is also available for Windows users (& it’s freeJ). Also, larger files can be loaded to the cluster manually by sending a DVD, Blu-ray disk or external storage device to PADT. The CoresOnDemand team will mount the volume and can assist in the copying of data.

## Step 2: Connect to the cluster and start jobs

Customers can connect to the cluster through an SSH connection. This is the most basic interface where users can launch interactive or batch processing jobs on the cluster. SSH is secure, fast and very stable. The downside of SSH is that is has limited graphical capabilities.

Another option is to use the Nice Software Desktop Cloud Visualization (DCV) interface. DCV provides enhanced interactive 2D/3D access over a standard network. It enables users to access the cluster from anywhere on virtually any device with a screen and an internet connection. The main advantage of DCV is the ability to start interactive ANSYS jobs and monitor them without the need for a continuous connection. For example, a user can connect from his laptop to launch the job and later use his iPad to monitor the progress.

Figure 1. 12 Million cell model simulated on CoresOnDemand

The CoresOnDemand environment also has the Torque resource manager implemented where customers can submit multiple jobs to a job queue and run them in sequence without any manual intervention.

Customers can use SCP or ship external storage to get data on the cluster. SSH or DCV can be used to access the cluster. Batch, interactive or Torque scheduler can be used to submit and monitor jobs.

# All Done?

Once the simulation runs are completed customers usually choose one of two methods to transfer data back. First is to download the results over the internet using SCP (mentioned earlier) or have external media shipped back (External media can be encrypted if needed).

After the customer receives the data and confirms that all useful data was recovered from the cluster, CoresOnDemand engineers re-image the cluster to remove all user data, user accounts and logs. This marks the end of the lease engagement and customers can rest assured that CoresOnDemand is available to help…and it’s pretty fast too.

At the end of the lease customers can download their data or have it shipped on external media. The cluster is later re-imaged and all user data, accounts & logs are also deleted in preparation for the next customer.

## ANSYS Launches Free Student Version

This week ANSYS, Inc. made a fantastic announcement that has been in the works for a while, and that we think will greatly benefit the simulation community:  A free ANSYS Student product.  This is an introductory product that is focused on students who are learning the fundamentals of simulation who also want to learn the full power and capability of the ANSYS product suite.  It includes ANSYS® Multiphysics™ , ANSYS® CFD™ , ANSYS® Autodyn®, ANSYS® Workbench™, ANSYS® DesignModeler™and ANSYS®DesignXplorer™

Yes you read that right, all of the flagship products for free. No features or capabilities are turned off. It is the exact same software as the commercial product, but the size of problems that you can solve is limited.  It runs on MS Windows. Perfect for students.

PADT is excited about this because it gives students access to the ability to learn FEA and CFD simulation with the world’s most popular and capable simulation tool, without running in to brick walls. Want to do a flat plate with a hole in it? No Problem. Want to model fluid-solid-interaction on a flexible membrane valve? No Problem.  Want to model explosive forming? No Problem.  Want to model combustion with complex turbulence? No problem.

All in the same interface as students will use when they enter the work force or do research at University.

This is great news and we can’t wait to see what schools and students do with this access.

## How to Get It – The New Academic Web Pages

The previous Student Portal is being replaced with an Academic Web area on the ansys.com site: ansys.com/academic.

Go to the ANSYS Student site to learn more about ANSYS Student and how to download your copy. These same pages will have resources to help you learn and understand the product.

## The “Pictures”

Let me state categorically that PADT was not consulted on the image that ANSYS, Inc. used for the “student” user that was so happy to find out that there is now a free version of the ANSYS software suite.  Here is their picture:

We would have preferred something like this:

Just kidding. We were happy to see this product come out and thought the picture was hilarious.  In all seriousness, we will also plug the  recent #ilooklikeanengineer twitter hash tag , highlighting the diversity of female engineers. that was awesome and we would love to see more chances for engineers to show their true selves.

## 3D Printing the 4th Dimension – GISHWHES 2015 Scavenger Hunt

GISHWHES is a huge international scavenger hunt. Every year teams around the globe comb through the list of 215 tasks and pick as many as possible that their team can do.  Last year they introduced 3D Printing as a task, and we helped a team 3D Print a quill pen. That was a lot of fun, so when this year’s list included an item on 3D printing, we jumped at the chance to be involved.

The item was:

110: VIDEO. Use a cutting edge 3D printer to 3D print your representation of the 4th dimension.62 POINTS

Being engineers we said “4th Dimension?  Time.”  Then it became a choice between the way mass distorts the space-time continuum or some sort of clock’ish thing.  The distortion thing seemed difficult so we focused on a clock.  Being that we were constrained on budget and time we decided to do a sundial.

The result can be seen here in this YouTube video.

It was a fun project and the team spent a bit of time in the 112F sunshine trying it out.  We can’t wait to see what we will get to do for the 2016 scavenger hunt.

# Making the Model

A couple of people have asked if we downloaded the solid model for the sundial or if we made it. We actually made it. After a little bit of research we found that making a simple horizontal sundial like this one is very easy. Here are the steps we took:

## Get Geometry Values

So it turns out that the angle of each hour line is determined by the latitude of where the dial will go. The angle of the pointy thing, called a gnomon, is also the latitude.  So for Tempe, AZ that is 33.4294°.That gets applied to the equation:

angle(h) = arctan(sin(L*tan(15° · h))

h = integer of the hour, 6 am to 6 pm
L = latitude

I plopped that into Excel:

and got the following:

 Latitude 33.4294 Hour Angle 6 90.00 7 64.06 8 43.66 9 28.85 10 17.64 11 8.40 12 0.00

## Build the Solid Model

The next step is to build the model. I used SolidEdge because I know it real well and was able to knock it out quickly.  But all CAD tools would be the same:

1. Pick a center point.
2. Add lines as rays from that using the angles in the table above for each hour.
3. Design the shape of your sundial to look cool. I did a simple circle .
4. Mark the hours using the sketch. I raised up thin rectangles.
5. Model the gnomon using the latitude as the angle.  Make this as fancy or simple as you want.
7. Label the hours if you want.
8. Save to STL

Here is what my sketch looked like:

And the final solid model looked like this:

We sent this to the printer as shown in the video, and got a sundial.

## Major Enhancements in FLOWNEX 2015: Combustors, Importers, and Pipes

Simulation has revolutionized flow and heat transfer dependent systems over the past decades by minimizing costly physical testing and accelerating time to operation around the world. But for many companies, such simulation has largely focused on components and proved to be very time consuming. The technology advancements delivered by Flownex SE now offer a fast, reliable, and accurate total system and subsystem approach to simulation.

With the release of FLOWNEX 2015, users now have access to advanced combustor system level modeling and they can interact with more system and component simulation tools. This is on top of the already considerable capabilities found in the  tool

## Gas Turbine Combustor Heat Transfer Library

During the Preliminary design phase or when considering modifications to existing combustor designs it’s essential to make realistic predictions of  mass flow splits through the  various air admission holes, total pressure losses liner temperatures along the length of the combustor etc.

Although very powerful, 3D CFD solutions of combustors are specialized, time consuming processes and therefore are seldom exclusively used during initial sizing of a combustor.

It has been demonstrated that 1D/2D network tools, like Flownex, are capable of predicting with reasonable accuracy the same trends as more detailed numerical models.

The advantage, however, is Flownex’s rapid execution, which allows design modifications and parametric studies to be conducted more simply than ever before. The ease of use and incredible speed of Flownex allows 1000s of preliminary designs to be evaluated under all modes of operation for steady state and dynamic cases. Furthermore, the data obtained from the one-dimensional analysis can be used as boundary conditions for a more detailed three-dimensional model, ultimately supplementing a typical combustor design work flow.

While the simulation of combustor systems was previously possible in the Flownex environment, much of the work of implementing industry standard heat transfer correlations was left to the user through scripting .Now in Flownex SE 2015 it’s all been built in to the tool, while maintaining the flexibility required to model any combustor configuration.

New components include

• Film convection component
• Fluid radiation component
• Jet impingement heat transfer component

To sum up Flownex allows more accurate initial designs, less time is spent on advanced 3D combustor simulations and rig tests, thus reducing development time and cost.

Here is a Video that shows off these features:

## Added importers and integration features

### AFT Fathom/Impulse/Arrow importer

An importer was added to import the file formats of AFT products. The importer imports all the diameters, loss factors heights, etc. so 90% of the effort is done, and in some cases the networks solve without any modifications.

ROHR2 Integration (pipe stress analysis software)

Flownex has the ability to calculate forces during dynamic simulations. This is very useful in pipe stress analysis for surge or water hammer cases. The ability to import complete geometries from ROHR2 and export results in the format that ROHR2 expects natively has been added. This means a user can perform these combined analysis now with ROHR2 with the minimum of effort.

Fluid Importers

An Importer was added to import liquid and gas properties from CoolProp an open source fluid property library. The existing Aspen/Hysys fluid importer was changed to be a generic Cape-Open compliant importer. This means that fluid properties can now be imported from any Cape-Open compliant server software.

## Donny Don’t – Thin Sweep Meshing

It’s not a series of articles until there’s at least 3, so here’s the second article in my series of ‘what not to do’ in ANSYS…

Just in case you’re not familiar with thin sweep meshing, here’s an older article that goes over the basics.  Long story short, the thing sweep mesher allows you to use multiple source faces to generate a hex mesh.  It does this by essentially ‘destroying’ the backside topology.  Here’s a dummy board with imprints on the top and bottom surface:

If I use the automatic thin sweep mesher, I let the mesher pick which topology to use as the source mesh, and which topology to ‘destroy’.  A picture might make this easier to understand…

As you can see, the bottom (right picture) topology now lines up with the mesh, but when I look at the top (left picture) the topology does not line up with the mesh.  If I want to apply boundary conditions to the top of the board (left picture), I will get some very odd behavior:

I’ve fixed three sides of the board (why 3?  because I meant to do 4 but missed one and was too lazy to go back and re-run the analysis to explain for some of future deflection plots…sorry, that’s what you get in a free publication) and then applied a pressure to all of those faces.  When I look at the results:

Only one spot on the surface has been loaded.  If you go back to the mesh-with-lines picture, you’ll see that there is only a single element face fully contained in the outline of the red lines.  That is the face that gets loaded.  Looking at the input deck, we can see that the only surface effect element (how pressure loads are applied to the underlying solid) is on the one fully-contained element face:

If I go back and change my thin sweep to use the top surface topology, things make sense:

The top left image shows the thin sweep source definition.  Top right shows the new mesh where the top topology is kept.  Bottom left shows the same boundary conditions.  Bottom right shows the deformation contour.

The same problem occurs if you have contact between the top and bottom of a thin-meshed part.  I’ll switch the model above to a modal analysis and include parts on the top and bottom, with contact regions already imprinted.

I’ll leave the thin sweeping meshing control in place and fix three sides of the board (see previous laziness disclosure).  I hit solve and nothing happens:

Ah, the dreaded empty contact message.  I’ll set the variable to run just to see what’s going on.  Pro Tip:  If you don’t want to use that variable then you would have to write out the input deck, it will stop writing once it gets to the empty contact set.  Then go back and correlate the contact pair ID with the naming convection in the Connections branch.

The model solves and I get a bunch of 0-Hz (or near-0) modes, indicating rigid body motion:

Looking at some of those modes, I can see that the components on one side of my board are not connected:

The missing contacts are on the bottom of the board, where there are three surface mounted components (makes sense…I get 18 rigid body modes, or 6 modes per body).  The first ‘correct’ mode is in the bottom right image above, where it’s a flapping motion of a top-mounted component.

So…why don’t we get any contact defined on the bottom surface?  It’s because of the thin meshing.  The faces that were used to define the contact pair were ‘destroyed’ by the meshing:

Great…so what’s the take-away from this?  Thin sweep meshing is great, but if  you need to apply loads, constraints, define contact…basically interact with ANYTHING on both sides of the part, you may want to use a different meshing technique.  You’ve got several different options…

1. Use the tet mesher.  Hey, 2001 called and wants its model size limits back.  The HPC capabilities of ANSYS make it pretty painless to create larger models and use additional cores and GPUs (if you have a solve-capable GPU).  I used to be worried if my model size was above 200k nodes when I first started using ANSYS…now I don’t flinch until it’s over 1.5M

Look ma, no 0-Hz modes!
2. Use the multi-zone mesher.  With each release the mutli-zone mesher has gotten better, but for most practical applications you need to manually specify the source faces and possibly define a smaller mesh size in order to handle all the surface blocking features.

Look pa, no 0-Hz modes!Full disclosure…the multi-zone mesher did an adequate job but didn’t exactly capture all of the details of my contact patches.  It did well enough with a body sizing and manual source definition in order to ‘mostly’ bond each component to the board.
3. Use the hex-dominant mesher.  Wow, that was hard for me to say.  I’m a bit of a meshing snob, and the hex dominant mesher was immature when it was released way back when.  There were a few instances when it was good, but for the most part, it typically created a good surface mesh and a nightmare volume mesh.  People have been telling me to give it another shot, and for the most part…they’re right.  It’s much, much better.  However, for this model, it has a hard time because of the aspect ratio.  I get the following message when I apply a hex dominant control:

4. The warning is right…the mesh looks decent on the surface but upon further investigation I get some skewed tets/pyramids.  If I reduce the element size I can significantly reduce the amount of poorly formed elements:
5. That’s going on the refrigerator door tonight!

And…no 0-Hz modes!
• Lastly…go back to DesignModeler or SpaceClaim and slice/dice the model and use a multi-body part.
3 operations, ~2 minutes of work (I was eating at the same time)

Modify the connection group to search/sort across parts

That’s a purdy mesh!  (Note:  most of the lower-quality elements, .5 and under, are because there are 2-elements through thickness, reducing the element size or using a single element thru-thickness would fix that right up)

And…no 0-Hz modes.

Phew…this was a long one.  Sorry about that.  Get me talking about meshing and look what happens.  Again, the take-away from all of this should be that the thin sweeper is a great tool.  Just be aware of its limitations and you’ll be able to avoid some of these ‘odd’ behaviors (it’s not all that odd when you understand what happens behind the scenes).