Using STAR-CCM+ for Research and Teaching at the Chair of Chemical - PowerPoint PPT Presentation

Using STAR-CCM+ for Research and Teaching at the Chair of Chemical & Process Engineering P ROF . D R .-I NG . M. K RAUME , G. W EHINGER , T. E PPINGER Chair of Chemical & Process Engineering Technische Universität Berlin STAR Global Conference 2014 (March 17-19), Vienna

Content 1. Introducing the chair of chemical & process engineering at TU Berlin 2. Single-phase research 3. Multi-phase research 4. Teaching CFD Slide 2 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

TU Berlin – Chair of chemical & process engineering Slide 3 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

SINGLE-PHASE RESEARCH Slide 4 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Single-phase stirrer vessels Temperature • Enzymatic membrane reactor pH control control  70 mm x 40 mm  90 mL Volume Adapter  H/D ≈ 1,8  Stirrer with d/D ≈ 0,9  Membrane at bottom • Single-phase CFD simulations: Inlet – Membrane fouling characteristics Membrane – Stirrer momentum Stirrer – Mixing time Shaft Outlet Lyagin et al. (2012). Chemical Engineering , 27 Slide 5 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Membrane fouling and shear stress Shear stress [PA] Enzyme: Acylase from Aspergillus Melleus Lyagin et al. (2012) Procedia Engineering , 44, 391-393. Slide 6 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Spatially resolved catalytic fixed-bed reactors DARS DEM Calculation of detailed (discrete element method) homogeneous and heterogeneous Generation of a random packing reaction mechanism Spatially Resolved Simulation of Fixed-Bed Reactors CFD - STAR-CCM+ Pore model Calculation of fluid dynamics, Calculation of processes within temperature and species pores concentration Slide 7 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Fixed bed generation using DEM simulations Filling by DEM-simulation  Fixed-bed geometry  Meshing  CFD simulation Spherical particles Non-spherical particles Eppinger et al. (2011). Chemical Engineering Journal , 166 (1), 324-331. Slide 8 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Work flow – non-spherical particles Raschig rings Raschig rings Cylinders one hole four hole D/d = 8.8 D = 0.22m d = h = 0.025m H = 0.55m Slide 9 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Catalytic fixed-bed reactors Coupling spatially complex geometries with detailed surface reactions Heterogeneous dry reforming of methane (42 irreversible reactions) 𝑤 𝑒 𝑞 𝑆𝑓 𝑞 = 𝜉 = 28 , T wall = 700 °C See the presentation by Gregor Wehinger : “Spatially Resolved Simulations of Heterogeneous Dry Reforming of Methane in Fixed- Bed Reactors” from 2:00 pm to 2:25 pm, Klimt I. Slide 10 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Mixing in biogas plants Challenges: • Shear thinning and viscoelastic fluids • multi-phase systems: solid, liquid and gaseous Biogas plant: substrate: corn silage 2 submersible mixers volume: 2500m³ Requirement: Correspondence of the agitators  S = 39 [Pa∙s 0.12 ] ∙  (0.12-1)  0 = 1000 Pa∙s  ∞ = 0.34 Pa∙s Slide 11 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Mixing in biogas plants Cavern forming in high viscous, shear thinning fluids  the correspondence of the agitators breaks down 2.40 1.92 1.44 0.96 0.48 0.00 Slide 12 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Permeation through a semipermeable membrane Feed side: c F (x,y,z) Retentate Feed 𝑵 Membrane 𝑵 Mass transfer as concentration dependent boundary condition Permeate side: c P (x,y,z) Permeate 𝑮 − 𝒅 𝒋 𝑸 𝒚,𝒜,𝒛=𝟏 For each component i: 𝑵 𝒋 𝒚, 𝒜 = 𝑴 𝑩 𝒅 𝒋 Concentration difference between Permeance feed and permeate side on Mass flow Area membrane surface  Implementation as user function Slide 13 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Application Details Gas permeation test cell Cross section Fluid volume Mesh Input Parameters Methane and n-butane mixture • p Feed , p Perm , 𝑊 𝐺𝑓𝑓𝑒 • Permeance L of membrane material • Trimmed Mesh • Slide 14 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Results Velocity profile Concentration profile Transmembrane -6,3*10 -5 kg/m² s bar mass transfer of n-butane: -6,6*10 -5 kg/m² s bar Slide 15 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

MULTI-PHASE RESEARCH Slide 16 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Multi-phase slim stirrer reactors • Combining CFD simulations and population balance equation  drop size and power consumption Slide 17 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Power number and Sauter mean diameter Slide 18 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

VOF-simulation of a silicon oil liquid film 0 cm  Film with constant height 4 cm  Regular beads  Irregular beads due to coalescence 20cm  Fewer but higher and faster beads 28 cm Wehinger et al. Chemical Engineering Science 104 (2013): 934-944. Slide 19 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Mass transfer at vertical liquid film Specific interfacial area depending on Mean gas-side Sherwood number gas load depending on Reynolds number Slide 20 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

TEACHING CFD Slide 21 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Teaching • Students are CFD users, not programmers • Theory: as much as necessary • Focus: solving engineering problems • Advantages of STAR-CCM+: CAD CAD modeler mostly simple geometries Post- GUI processing Hierarchical model selection Reports, Monitors, Animations Slide 22 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Example: Hippopotamus pool in the zoo of Berlin • Three hippopotami in the pool • Water turbidity in the pool due to biomass disposal • Pool: 600 m³ and 160 m³/h  Velocity distribution and residence time Simplified geometric model Slide 23 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Water turbidity by evaluating velocities Velocity distribution at different levels in the hippopotamus pool  Dead zones indicates water turbidity Pressure outlets Velocity inlet Slide 24 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Conclusion • We are applying computational fluid dynamics regularly. • Special objections need special solutions, e.g., user defined subroutines. • CFD accompanies and/or enriches specific experiments at different length and time scales. • CFD references and is likewise referenced by experiments. Slide 25 Chair of Chemical & Process Engineering STAR Global Conference 2014 www. verfahrenstechnik.tu-berlin.de Vienna, March 17-19, 2014

Thank you for your attention. Prof. Dr.-Ing. M. Kraume, G. Wehinger, T. Eppinger Chair of Chemical & Process Engineering Technische Universität Berlin STAR Global Conference 2014 (March 17-19), Vienna