The new generation of electrorheological fluids (ERFs) offers a wide range of applicability in fluid mechatronics with automotive ERF devices such as ERF shock absorbers mentioned at first place. The optimal design of such tools requires the proper modelling and simulation both of the operational behaviour of the device itself as well as its impact on the dynamics of the complete vehicle. This paper addresses these issues featuring an extended Bingham fluid model and its numerical solution as well as substitutive models of viscoeleastic-plastic system behaviour. Also control issues for optimal semi-active suspension of vehicles with controllable ERF shock absorbers are discussed.

In the framework of the macroscopic simulation of electrorheological fluids, we present an extension of the classical Bingham model which goes beyond pure shear flows and thus enables the simulation of settings in more complex geometries. Emphasis is on the numerical solution of the resulting nonsmooth minimization problem. We propose the method of augmented Lagrangians combined with an operator-splitting technique which allows to confine the nonlinearity to local, low-dimensional problems. Numerical results are given that illustrate the electrorheological effects for various shear rates and electric field strengths in case of an electrorheological suspension rotating between two revolving cylinders.

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High power electronic devices based on innovative semiconductor technology playa significant role in technical applications. A robust operating behavior of such devices can be achieved by an optimal design taking into account the presence of coupled physical effects. In this contribution, we focus on electrothermomechanical coupling phenomena in Integrated-High-Voltage Modules with housing and cooling mechanisms that are used as electric drives for high power electromotors. For the numerical solution of the underlying coupled systems of partial differential equations we consider efficient algorithmic tools such as domain decomposition techniques.

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