Application of Computer Aided Engineering (CAE)

In the Biofluid Mechanics Lab the development of new products and systems is based on methods of CAE. CAE integrates the design and the manufacturing of products. The related processes are called Computer-Aided Design (CAD) and Computer-Aided Manufacturing (CAM). In a CAE system, drawings developed and revised during the design process are converted directly into instructions for the Computer Numerical Control (CNC) milling machines.

The Biofluid Mechanics Lab uses a 3-dimensional CAD software to generate solid model geometries. Design improvements can be integrated into the 3D model with little effort compared to conventional 2D design.

Additional tools like calculation software for strains/stresses and Computational Fluid Dynamics (CFD) provide simple data exchange for:

• Manufacturing of mechanical parts and moulds using CNC milling machines

The blood pump shown on the right is part of a pneumatically driven Left Ventricular Heart Assist Device (LVAD).

Blood pump

• Strain/stress calculation using Finite Element Method (FEM)

Blood chamber of the blood pump. As a part of the FEM-calculation a solid mesh was generated consisting of more than 50.000 parabolic tetrahedral elements.	Solid mesh of the blood chamber
Resulting displacement in the endsystolic state of the blood pump.	Displacement
The image shows the strain values plotted on the deformed shape of the model. The blood chamber is diagonally cut in order to show the strain values on the inside of the material.	Strain values

• Calculation of fluid dynamics with the methods of CFD

This image shows the enclosed fluid volume of an LVAD's blood pump. The structure can be imported into a CFD calculation program like FLUENT.

CFD-Volume