CFD-Berlin has a long record of experience in the application and improvement of own CFD codes as well as custom software.
This applies to consulting as well as implementation on our protected servers.
We have extensive expertise in research and development regarding numerical aeroacoustics / computational aeroacoustics (CAA). Common cases relate to sound propagation in flows with sound-absorbing surfaces even in areas with complex boundary. Examples are the inlet or bypass channel of aircraft engines and blowers for (industrial) air conditioning (HVAC) applications. With advanced solvers and in-house tools, we perform optimisations of acoustic absorbers with a large number of parameters > liner optimisation.
Our CAA solver CFDNoise is based on the Euler differential equations (linearized / nonlinear) that can be used to simulate sound propagation in flows. For the solution, a numerical method high-order method, especially optimised for sound propagation, is used. Sound sources can be simulated with modal and broadband stimulation. Acoustic absorbers are used as an impedance boundary condition with flexible frequency dependence. This allows to optimise novel liner concepts such as the Special Acoustic Absorber (SAA) Liner, which – because of complexly shaped resonance spaces – provides complex variations in damping characteristics.
Effio is a framework for optimised output and processing of non-stationary / time-dependent data. Problems relate to large data sets, file system instability due to too many files, blockages through simultaneous access to shared I/O resources, and file-compatible file formats for solvers and tools. To address these problems, Effio has been developed. It provides ‘in one operation’ and in parallel, data for many grid points and several time steps. In the form of a library, it can be easily and minimally integrated into various solvers and tools in C/C++ as well as in Fortran. The output format is set jointly by configuration files. When for simple operations, e.g. averaging of data, they need to be processed by external tools, which requires to read entire data sets, Effio performs equations with simple post-processing operations (min, max, mean, exponential smoothing,…) at the time of the solution. This enables parallel processing and saves enormous work steps / computing time.