Overcoming the Barriers Imposed by Geometry SpaceClaim Empowers CAE Analysts

Transcription

1 Overcoming the Barriers Imposed by Geometry SpaceClaim Empowers CAE Analysts July 2011 A CIMdata Report

2 Overcoming the Barriers Imposed by Geometry SpaceClaim Empowers CAE Analysts July 2011 Produced by CIMdata, Inc. CIMdata, Inc Research Park Drive, Ann Arbor, Michigan Tel: +1 (734) Fax: +1 (734) CIMdata is a Registered Trademark of CIMdata, Inc. Copyright 2011 by CIMdata, Inc. All rights reserved.

3 Overcoming the Barriers Imposed by Geometry SpaceClaim Empowers CAE Analysts CAE analysts often face the burden of poor quality and over-detailed geometric models in preparing finite element meshing for analysis. However, end users of SpaceClaim Engineer testify that the application is making a valued impact to alleviate these barriers. To surmount those problems, a solution must be able to import an extensive range of CAD model formats found in the industry and also support an intuitive user interface that is easy to learn for non-cad experts. SpaceClaim boasts a positive record in each case in the opinion of their customers. McCormick Stevenson, an engineering services company, finds that SpaceClaim serves as a great arbiter of geometry and boasts, anything can be imported. The broad appeal of SpaceClaim Engineer as a tool for CAE analysts is further touted by Stig Staghøj Knudsen, a naval architect and CFD expert from Ramboll Group A/S in Denmark. For them, SpaceClaim cleans up CAD models in new ways not previously available saving a lot of product development time in the process. 1. Introduction During the product development process, CAE analysis offers developers an important opportunity to validate and improve product reliability and quality. However, analysts are often thwarted in their attempts to respond with timely simulation results due to the burden of poor quality and over-detailed geometric models. In order to properly mesh the models for finite element analysis, a CAE analyst faces the necessity to first resolve topological inaccuracies such as gaps and small sliver surfaces in the geometry. The analyst must then simplify the model by de-featuring the geometric detail by removing things such as small holes, slots, and rounds that design has added for final manufacturing. It is essential to meshing that a model be watertight by eliminating any gaps in its geometry. These holes or flaws are often formed by mismatched vertices or edges between solid model faces created by importing CAD models generated with loose tolerances or by approximations done during CAD data translations. The existence of gaps in the model can easily disrupt the execution of building a finite element mesh on the model. Small sliver surfaces are often generated when intersecting surfaces and adding fillets to freeform shape models, and they must be removed to avoid over complicated meshing. In addition, CAE analysts based on their individual judgment will remove geometric details, which were added to support manufacturing by the designers, so as to further unburden the meshing algorithm. The extent of the challenge imposed by these two barriers is corroborated in previous CPDA/CIMdata research. A study on CAE Model Clean Up across numerous industry verticals indicated that seventy-five percent of CAE analysts interviewed faced the need to correct model errors. In addition, eighty-eight percent in the study faced the need to de-feature their models. These concerns are further compounded by yet another barrier that many CAE analysts face in dealing with Figure 1 A Detailed Model and Its De-Featured Variant Removing Geometry Barriers for CAE A CIMdata White Paper Page 1

4 geometric models the broad array of possible geometric data formats they must process. Many product developers assert today that product development is a multi-cad endeavor. Whether the analyst serves a product manufacturing company working with diverse supply chain partners or represents a member of an outsource service company doing analysis for a range of clients, the CAE analyst must be ready to accept CAD models in a wide range of proprietary and industry-standard formats. They require tools that can uniformly deal with the challenge. 2. A Geometry Simplification Solution Recently, many firms are turning to SpaceClaim Corporation for a solution. 1 The company has positioned their product, SpaceClaim Engineer, as a leader in 3D direct modeling for rapid concept design and geometry manipulation. To succeed in this role, a product must be able to import the extensive range of CAD model formats found in the industry and offer an intuitive user interface that is easy to learn for non-cad experts. SpaceClaim boasts a positive record in each case, as testified to by their customers. McCormick Stevenson Corporation is a mechanical engineering services firm for the defense and aerospace industries headquartered in Clearwater, Florida. 2 It specializes in mechanical packaging and integration of electronic systems used in harsh military environments. The company s President, Noel McCormick, reflects on the state of the technology: In my experience, without adequate simplification to the model, the finite element iterative process can go wildly out of control from a manhours standpoint. Mr. McCormick continues, For years CAD vendors have told a story that developers can use the same geometry for analysis that they use for design. In our experience, that has never been true. He notes that once an analyst receives a model, it takes time to prepare the data and perform the actual simulation. The CAD design model, 1 For information on SpaceClaim Corporation and the SpaceClaim Engineer product, see 2 For information on McCormick Stevenson Corporation and their services, see however, continues to progress and the model data sets evolve quickly out of synch. For that reason alone any recommended changes to the model from the CAE analyst are communicated verbally. McCormick Stevenson chose SpaceClaim Engineer for their CAE analysts. After admitting to an initial hesitation because SpaceClaim Engineer is not a traditional parametric, history-based modeling application, Noel notes they recognized that once a CAE analyst makes a change to the model in preparation for analysis, It is no longer design geometry. So moving it to SpaceClaim is a non-issue. Further, he indicates that while de-featuring holes is not critical in their typical models, they will mid-surface parts wherever they can within an assembly, and then de-feature unnecessary rounds. His assessment: SpaceClaim, with their selection tools, makes that very easy. He continues, We have also created geometry without any hesitation. No training was necessary. Given that we are a consulting firm, SpaceClaim offers us potential benefits because it is a great arbiter of geometry. We can import anything into it once it is there, the design potential is obvious. Figure 2 SpaceClaim Allows Removal of Non-Critical Features to Facilitate Meshing The broad appeal of SpaceClaim Engineer as a tool for CAE analysts is further touted by Stig Staghøj Knudsen, a naval architect and CFD expert from Ramboll Group A/S, an engineering, design, and consultancy company headquartered in Denmark. 3 In a similar circumstance to 3 For information on Ramboll Group A/S and their services, see Page 2 A CIMdata White Paper Geometry Barriers for CAE

5 Figure 3 Once Imported into ANSYS the SpaceClaim Model is Analyzed with Reduced Computational Time Due to Its Simplification that experienced by McCormick Stevenson, Mr. Knudsen notes that Ramboll, as a large contractor, gets data from a number of industries, all of which use different CAD software. He also reflects on the varied quality of the data they receive. In just over the past year and a half, they have selected SpaceClaim as their tool of choice for handling disparate imported CAD data and preparing those models for analysis. Mr. Knudsen offers, We used to redraw things from scratch. With SpaceClaim we have the ability to clean up CAD in ways we did not have before and it has saved us a lot of time. He speaks to one example of a client supplying a large model and drawings and Ramboll s ability to prepare the model and analyze it within one week using SpaceClaim, whereas he estimates it would have previously taken three weeks. He notes, We get a lot of different geometries and we don t want to waste a lot of time on geometry. Often on very large CAD models with extensive manufacturing detail, we use SpaceClaim s de-featuring. They have a lot of good tools to do both fix errors and defeature, especially for industrial products. Mr. Knudsen highlights a special point that underscores their use of SpaceClaim the fact that there is no one simple solution to prepare a CAD model for simulation. He notes that, Different tools are needed to prepare the models. There is no easy answer as to which one to use. The last fix you used may not be the correct one for the next problem. With SpaceClaim we can always find a solution. It rapidly becomes apparent that an overriding requirement for any tool that attempts to facilitate the preparation of CAD models for meshing and simulation done by a CAE analyst is that it not only have the necessary functional capabilities, but it must also be intuitive and easy to use. Often, however, those attributes are difficult to define and articulate. Yet SpaceClaim has captured much of the essence of these requirements as validated by its customers, including Martin Schagerlind, Simulation Engineer at Vicura in Sweden. 4 Vicura is an engineering company specializing in driveline technology that originated in early 2011 from General Motors Powertrain and Saab Automobile Powertrain AB. He notes that with his first look at SpaceClaim he was impressed with its ease of use. Now that he has chosen SpaceClaim for his work he confirms that the application is very efficient. Mr. Schagerlind notes that overall the power and flexibility in SpaceClaim allows model clean up five times faster than functions found in the meshing tool set they use. Prior to having the CAE analyst clean up the model, changes had to be requested from the designer, leading to delays. He also noted that customer communications have improved by using SpaceClaim s ability to do cross-section renderings. 3. Summary and Concluding Remarks The reduction of the product development cycle while improving product quality and reliability remains a strategic goal in all manufacturing companies. The CAE analyst relies on an iterative cycle of model, clean up, mesh, and analysis to make recommendations for product improvement. The tools they use directly impact their productivity. In the CAE analyst world, SpaceClaim is making a valuable impact as testified to by its users. SpaceClaim is helping them overcome the barriers imposed by model geometry. Research for this paper was supported by SpaceClaim Corporation. About CIMdata CIMdata, a leading independent worldwide firm, provides strategic management consulting to maximize an enterprise s ability to design and deliver innovative 4 For information on Vicura and its products and services, see Removing Geometry Barriers for CAE A CIMdata Report Page 3

6 products and services through the application of Product Lifecycle Management (PLM) solutions. Since its founding more than 25 years ago, CIMdata has delivered world-class knowledge, expertise, and best-practice methods on PLM solutions. These solutions incorporate both business processes and a wide-ranging set of PLM enabling technologies. CIMdata works with both industrial organizations and suppliers of technologies and services seeking competitive advantage in the global economy. CIMdata helps industrial organizations establish effective PLM strategies, assists in the identification of requirements and selection of PLM technologies, helps organizations optimize their operational structure and processes to implement solutions, and assists in the deployment of these solutions. For PLM solution suppliers, CIMdata helps define business and market strategies, delivers worldwide market information and analyses, provides education and support for internal sales and marketing teams, as well as overall support at all stages of business and product programs to make them optimally effective in their markets. In addition to consulting, CIMdata conducts research, provides PLM-focused subscription services, and produces several commercial publications. The company also provides industry education through PLM certification programs, seminars, and conferences worldwide. CIMdata serves clients around the world from offices in North America, Europe, and Asia Pacific. To learn more about CIMdata s services, visit our website at or contact CIMdata at: 3909 Research Park Drive, Ann Arbor, MI 48108, USA. Tel: Fax: ; or at Oogststraat 20, 6004 CV Weert, The Netherlands. Tel: +31 (0) Page 4 A CIMdata White Paper Geometry Barriers for CAE

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