automotive

The B-pillar is an important load carrying component of any automobile body. It is a primary support structure for the roof, and is typically a thin-walled, spot-welded, closed-section structure made from high strength steels. As part of the validation process, the B-pillar can be ex-perimentally loaded at quasi-static rates until failure†. The force and displacement of the impactor are measured to get valuable insight into the stiffness characteristics of the structure.

During product development, design engineers often have the freedom to modify a number of parameters. However, any design modification requires validation to ensure the satisfaction of requirements for all load cases. With Abaqus for CATIA V5 (AFC), nonlinear finite element technology is made available within the CATIA environment, allowing design engineers to efficiently incorporate accurate stress analysis into the design process. In this Technology Brief two approaches are described to illustrate the productivity gains possible with AFC.

This technology brief illustrates typical mode-based noise, vibration, and harshness (NVH) analyses of a full automobile model using the Abaqus product suite. Abaqus/AMS, the automatic multi-level substructuring eigensolver, is used to compute the eigensolution. A steady-state dynamic analysis is then performed in Abaqus/Standard. The significant performance benefit of using Abaqus/AMS and the SIM-based linear dynamics architecture will be demonstrated for uncoupled structural and coupled structural-acoustic analyses.

A methodology to study the sound radiation of engine valve covers is presented. The analysis process uses a nonlinear static simulation followed by a steady state dy-namics simulation to determine the sound pressure field due to the vibration of the engine cover. The effects of assembly loads are included. The methodology is dem-onstrated with two representative engine valve covers using acoustic finite and/or infinite element methods. Good correlation between the analysis results and avail-able experimental data is achieved.

The National Highway Traffic Safety Administration (NHTSA) mandates the use of certain test procedures to determine automobile roof crush resistance. In the test the force-deflection behavior of the roof structure is meas-ured by quasi-statically pressing a precisely positioned rigid plate against the automobile. As part of the design process, the test is often simulated analytically. As with many quasi-static processes, the roof crush resis-tance test can be simulated in Abaqus/Standard or Abaqus/Explicit.

A methodology to study friction-induced squeal in a com-plete automotive disc brake assembly is presented. The analysis process uses a nonlinear static simulation se-quence followed by a complex eigenvalue extraction to determine the dynamic instabilities that are manifested as unwanted noise. The effects of assembly loads; nonuni-form contact pressure between the brake linings and disc; velocity-, temperature-, and pressure-dependent friction coefficients; friction-induced damping; and lining wear can be included. The methodology is demonstrated with a representative disc brake assembly.

Spot-welded, thin-walled curved beams, which constitute the main structural members in many automobile and other ground vehicle body structures, play a significant role in absorbing energy during a collision. Due to their extensive use, it is important to study the collapse charac-teristics of these curved members (Ref. 1). Abaqus/Explicit can be used effectively to simulate the quasi-static collapse of spot-welded structural members accu-rately.

A wide range of loading conditions must be considered in the design of a tire. Computational simulations of a quasi-static, steady-state dynamic and nonlinear transient dy-namic nature must be completed. In addition, the com-plexity and size of typical tire models highlight the need for efficient solution techniques.

This work describes a numerical methodology based on the Finite Element approach able to simulate the dynamic maneuver of the full vehicle running on fatigue reference roads. The basic idea of present work stays in combining a moderately complex and general tire model with traditional full-vehicle methods, including both implicit and explicit finite element techniques, in order to predict – within the early design phases when no prototypes are available - the loads transmitted to the vehicle running on the real fatigue reference roads.

Snow traction is an important tire performance parameter for product applications in markets where snow is present for several months during the year. It is very difficult to perform multiple tests because proving grounds and consistent test conditions are available only for limited periods of time and due to prototyping and test expense. This paper deals with the simulation aspects of the snow traction test using Abaqus. The first part of this paper describes the chosen test method and offers a review of the available simulation technology.