## flow simulation

#### Example calculations of the following physical topics include:

• sonic and sub-sonic flows
• stationary- or transient flow calculations
• mixing of gases, liquids and particles free and forced convection
• multi-phase mixtures
• chemical reactions; particle, gas, liquid, surface reactions
• adsorption, absorption
• heat radiation
• electric field forces abrasion of materials or growing on surfaces or particle growth
• phase change: evaporate, condense, solo exploding, melting, sublimation
• convection in pumps and fans, optimization and wear reduction
• aerodynamics
• aero acoustics
• filling processes
• laminar and turbulent flows

Theory and practice

Flow simulations are based on the numerical solution of the Navier-Stokes-equations which area an analytic description of flow processes. Those equations can be combined with equations on energy and material transport to display heat transport or distributions of concentrations.

CFD (Computational Fluid Dynamics) simulation technology means that the infinite number of degrees of freedom that a fluid continuum has can be projected to a finite number of points in space and converted into matrix equations by means of suitable mathematical procedures. The discretion is done using CFD software programmes that enable the user to resolve the complex equation systems on modern computers with reasonable effort. When reducing the continuum of the finite number of points, a calculation lattice results where the physical information of the lattice point is computed from the values of the surrounding lattice.

The final simulation model is then derived from this calculation lattice, while referring to the physical models relevant for the specific case (e. g. turbulent, laminar, multi-phase etc.), from the material parameters (density, viscosity, heat conductivity, etc.) and the framework conditions (volume flow, temperature, adhesive friction, etc.). Eventually, the numerical fluid computation delivers the physical parameters required which allow for reading and evaluating the quantity and quality of velocity and temperature distributions, pressure, streamlines etc.

Our success is not only rooted in the adequate interpretation of the simulation results, but even more so in the analysis of their economic use and applicability.