Sign In
Forgot Password?
Sign In | | Create Account

On a Wing and a Prayer - Part Deux

Nazita Saye

Nazita Saye

Posted Nov 24, 2010

It seems that my previous post resonated deeply with everyone – I received a lot of offline comments and my post inspired two of my colleagues (Boris and Andras) to do their own blog posts. This doesn’t shock me because Thanksgiving week is one of the busiest travel periods in the States so everyone is thinking about flying. So I thought we should stay with the subject for one more day and look at it from another angle.

On that faithful flight, soon after the engine blew up, 54 separate alarms (yup 54) went off in the cockpit. With so many alarms going on at the same time, some warning of imminent loss of critical systems, understanding and prioritizing between the various alarms must have been a daunting task. Luckily there were 5 pilots with a combined flight time of 100 years in the cabin at the time of the incident. So one pilot concentrated on actually flying the plane (not an easy task since the plane was rather unresponsive due to engine shrapnel severing lots of cables in the wing) while the others dealt with the various alarms. In all it took 50 minutes to process the various messages and they were able to land the plane without any other major incidents. Once they landed, the investigators pored over the damage and as a result they’ve learned a few things. One significant finding is that systems should be separated so that one single point of failure couldn’t damage the entire system. And that brings us to today’s topic: interdependencies in design.

Unless you work for a small organization, you won’t have enough insight into all the various systems in a complex product. Let’s take a car for example. Cars consist of many systems … each designed to work in harmony with the other. Yet they are rarely if ever designed that way. Chances are that the various components and or systems are made by several specialist tier 2 and tier 3 organizations. All good enough because quite frankly having specialists work on the various aspects ensures the best possible design for each respective component. That’s where our solutions come in – a thermal specialist works on the LED headlights with FloTHERM, the mechanical engineer works on the hybrid engine with FloEFD, another works on the dual temperature zone to ensure passenger comfort with FloVENT and lastly the QA team tests the reliablity of the LED with T3Ster. But at some point, all these subsystems need to come together to create one entity.  How do you ensure that the whole system can work together?

Building a physical model to test everything is expensive and going to the market with an untested product … well… we all know what I think about that. I remember watching an automotive show a couple of years ago. The host was doing a test drive on a new car and seemed happy enough with the handling of the car. But he went a bit berserk when he tried to take a CD out of the dash and was unable to do so because the gear lever was in the way when the car was parked. It seemed that whoever did the layout didn’t really think about the whole system (or he/she didn’t mind changing CDs while driving a car). Hmm… there goes that pesky issue with interdependencies…

That’s why it’s important for engineering managers to invest in solutions that work with one another in order to support a holistic design process. A few of the CAD vendors offer this type of solution. For example, PTC offers a tool called Creo Elements/View. With this tool you can bring in content from many different sources to view, mark-up and interact with the digital version of your product. In other words, you’d optimize your design for flow and heat transfer and transfer the final design data into a collaboration tool and watch your design come to life.

A few years ago I heard about a major agricultural vehicle manufacturer who used to create full scale foam-core mock-ups of their vehicle cabins for test purposes. They’d haul the “test” vehicle into the parking lot in the middle of the night while sporting a few flashlights to test for visibility and to see whether the operator could access the various levers. Perhaps visibility in a tractor may not seem that big of a deal to you and me but remember farm vehicles use the same roads as us. So you don’t want them to plow into you because the operator was unable to see you or reach a specific lever. Invariably after each of these test sessions, they needed to tweak the design. So they would spend 6 weeks on the redesign and creation of another mock-up.

Once they started using a collaborative design tool, they were able to modify the model and immediately use a head mount display to immerse themselves into the digital product and to test it – drastically cutting the time and expense needed to test new design ideas. I guess their system was very similar to those flight simulators you see used for training pilots. They could even simulate fog, something they couldn’t do in the parking lot in the middle of the night. They no doubt even used that digital mockup to train their mechanics on how to fix problems. The end result? A product which was tested and optimized for operability, ergonomics and safety without spending a dime on building a phsycial prototype.

By using a holistic design approach and through a combination of CFD simulation and collaborative design tools you could create the best possible components, test their interdependencies and ensure that one failure doesn’t create a cascading effect. And it’s a lot more reasonably priced to implement than you might think. All you need is the imagination to see how it would work for your organization, find the right solution partners and make it happen.
Until next time,


PS. I would like to wish everyone back home a very Happy Thanksgiving. I’m a bit nervous as I’ll be cooking my first Thanksgiving dinner all on my own. Wish me luck!

T3ster, Thermal, CFD, LED, QA, FloVENT, hybrid engine

More Blog Posts

About Nazita Saye

Nazita SayeI have been involved with the CFD user community in one shape or another since 1999 -- when the NIKA team first introduced FloWorks to the engineering community. Over the years I've seen the market evolve and I still marvel at the wide range of products that are being designed with our tools. As the Manager of External Communications for the Mechanical Analysis Division at Mentor, it is my privilege to bring some of our customer stories to you. Visit CFD doesn’t mean Color For Directors

More Posts by Nazita Saye


No one has commented yet on this post. Be the first to comment below.

Add Your Comment

Please complete the following information to comment or sign in.

(Your email will not be published)


Online Chat