Experimente und gekoppelte CFD‐Simulationen von Wärmeübergängen an Rohrschlangen in Fermentern und Rührreaktoren

This study provides the influence of different heat exchanger internals (helical pipe coils, heating plugs, pipe registers) and reactor bottom shapes (torispherical/dished (Kloepper-shape), hemispherical, and flat) on the flow field, the turbulent kinetic energy, and the ratio of tangential flow in stirred vessels, based on extensive stereo PIV measurement series in refractive index-matched, optically completely accessible systems. The investigations impressively show advantages and disadvantages of the various equipment, which have a massive influence on both heat transport and the flow.

Section: Theoretical Backgroundmentioning

confidence: 99%

Flow Fields in Stirred Vessels Depending on Different Internal Heat Exchangers and Vessel Bottoms

Jaehrling

Schultz

2019

“…For the evaluation and design of mixing and suspending processes, dimensionless parameters are used to describe the flow state, power input, quality of suspension and the behavior of the suspended particles , . While there are plenty of simulated CFD data available in literature for suspension reactors, practical measurement data for stirred vessels with internals are lacking.…”

Section: Theoretical Backgroundmentioning

confidence: 99%

Optical Measurement Method of Particle Suspension in Stirred Vessels

Wolinski

Ulbricht

Schultz

2019

Suspending particles in liquids is an important and versatile case for industrial stirring processes. By using advanced optical, non‐invasive measurement techniques like particle image velocimetry (PIV), it is possible to gain deep insights into the involved fluid dynamics without affecting the flow. However, for suspensions, the application of PIV is not trivial since both, suspended and tracer particles are present and need to be discerned during experiments. The here presented method development solves this problem and thus leads to a better insight into turbulent kinetic energy distribution, which can be utilized for process optimization through improved stirred vessel design.

“…Then, e.g., Oldshue and Gretton came up with a construction guideline , . Although some constructions of stirred vessels with helical coils and of vessels with and without baffles had been studied in the meantime , the guideline of Oldshue and Gretton for the helical coils is still often used for today's engineering.…”

Section: Introductionmentioning

confidence: 99%

Particle Image Velocimetry Compared to CFD Simulation of Stirred Vessels with Helical Coils

Jährling

Wolinski

Stefan

et al. 2017

The results of measurements using two different particle image velocimetry (PIV) systems (2D-PIV versus stereo-PIV) are compared and the obtained data with a coupled CFD simulation are also correlated. A stirred vessel with internal helical coil as additional heat exchanger is analyzed with these settings. Results for the velocity fields and turbulent kinetic energy distribution are shown and the feasibility of stereo-PIV measurements by using refractive index matching fluid is proven. This investigation provides a good accordance and consistency between the different PIV systems and the related CFD.