Simulations How Simulations Drastically Reduce the Development Time of Cars
The limits of computer-aided simulations are far from exhausted. At the Altair Technology Conference, the simulation specialist presented a variety of interesting applications with a focus on the automotive industry.
Today, hardly any car goes into production without being thoroughly tested in simulations. This is also necessary as product cycles become ever shorter: The development of a new car takes three to four years. Then the car is sold for six to eight years. Even though these numbers vary somewhat from manufacturer to manufacturer, today all car manufacturers are exposed to much greater time pressure than a few years ago. The much-discussed digitalization of processes has long since found its way into the automotive industry. New models are created with CAD software. Data management and team collaboration are supported by PLM software, and prototypes of parts, assemblies or complete bodies are being produced less frequently than real models.
From October 16 to, 2018, Altair demonstrated at its global user conference in Paris how product development can be accelerated through the use of simulation, artificial intelligence, and additive manufacturing. Around 800 participants followed the invitation of the American software manufacturer with a focus on CAD and simulation software and listened attentively to more than 140 presentations. Industry seminars and in-depth technical sessions dealt with topics such as design for manufacturing, lead time reduction, fatigue simulation, design for additive manufacturing, e-mobility, system simulation, and IoT (Internet of Things).
Structural Simulations do not Require Geometric Simplification, Cleanup or Networking
The conference started with a sensation: James R. Scapa, Founder, Chairman and CEO of Altair, announced the acquisition of competitor Simsolid. Simsolid's simulation technology is used by engineers, designers, and computational engineers worldwide The software is based on detailed CAD assemblies and provides fast, accurate, and robust structural simulations without the need for geometric simplification, cleanup, or networking. The underlying technology is largely based on the work of Dr. Victor Apanovitch, a former professor at the Belarusian National Technical University and co-founder of Simsolid. The expansion of Altair's portfolio is expected to offer major benefits to its customers, particularly with regard to simulation.
Virtual Product Development Instead of Crash Tests
These days, no automobile manufacturer can do without simulation technology. Cost and time pressure in product development set clear priorities. This is especially apparent in the example of the vehicle crash test, a classic of simulation applications. In the past, dozens of cars were literally driven against the wall to assess the behavior of bodywork or restraint systems. Then realistic simulations came into play that virtually modelled the real behavior of components using the finite element method to achieve high prediction quality. Over the past few years, these simulations have gained such precision that some car manufacturers have now largely abandoned physical crash tests in the development phase. Small changes to the bodywork, which used to require a lot of effort, now require only a few mouse clicks and a few hours of computing time in virtual product development to simulate variations in crash behavior.
Jaguar I-Pace: Development Time Reduced from 18 Months to 12 Weeks
A presentation by Mark White, former Head of Body Development at Jaguar Land Rover, showed the potential offered by modern tools. He focused his lecture on the development of the Jaguar I-Pace, the first electric vehicle produced by the traditional British manufacturer. The entire vehicle was newly developed and adapted to the requirements of a purely electric vehicle. A few facts made the audience sit up and take notice: By using 94 % aluminum components, it was possible to reduce the weight of the body to just 258 kilograms. Nevertheless, the entire body is still stable enough to accommodate a large panoramic roof. In the crash simulations, special attention was also paid to the installation space of the battery to ensure maximum safety.
One Million Hours of Simulated Tests Instead of Countless Real Prototypes
Using the B-pillar, which plays an important role for both the stability and crash safety of the I-Pace, White demonstrated in detail the advantages of simulation in interaction with the CAD software: Design variants can be tested, evaluated, and modified with new parameters within a very short time. Numerous flow simulation tests examined aerodynamics until a CW value of 029 was achieved. According to White, "a very acceptable value" for an SUV.
White says the use of Altair tools has resulted in many advantages: Development time has been reduced from 18 months to 12 weeks; real driving tests have been reduced by 750,000 miles, saving more than 300 tons of CO2. A large number of real prototypes were not required anymore, thus reducing costs. To achieve this goal, more than a million hours were spent on simulation tests and around 1,000 years of computing power on high-speed computers (HPCs) were used.
C123 Methodology Provides Early Feedback in the Design Phase
Another exciting development approach was presented by Andrea Merulla, Head of Concept and Innovation at Ferrari: the C123 methodology. Altair designed this development approach, which provides the engineer with early feedback and conclusions during the design phase. C123 is a very flexible approach in which optimization is carried out on the basis of three different levels of abstraction of the BIW (Body in White). In abstraction level C1, the vehicle is constructed as a construction model in order to determine load paths (basic questions on construction spaces, vehicle architecture, etc.). In stage C2, a model consisting of special beam elements and coupled cross-section information is used to perform rapid variant optimization. The abstraction level C3 basically corresponds to the conventional method based on shell models. In order to simulate and optimize shell models quickly, however, details that are not required for basic design decisions are often omitted. Simulation-driven development is aimed at helping to point in the right direction, evaluating design alternatives, and finding the best possible balance between all development attributes. Ferrari uses this approach to test variant constellations.
Some of the presentations also dealt with "Digital Twins". This concept is suitable for use in a PLM strategy involving many product variants and allows all the data for a product to be available at the touch of a button: from the idea and design to production. The digital twin is the exact virtual model of a product or production line. It represents the development over the entire life cycle and enables the prediction of behavior, the optimization of performance, and the implementation of results from previous design and production experiences.
This article was first published by konstruktionspraxis.