Timo Merbach, M.Sc.

 


Denickestr. 15

Building K, Room 0512

21073 Hamburg

Phone +49 40 30601 - 2031

Mail Timo Merbach


 

Biography

Timo Merbach studied Process Engineering at Hamburg University of Technology (TUHH) from 2017 to 2020, where he completed his bachelor’s thesis on mass transfer in aerated stirred tank reactors at the Institute of Multiphase Flows (IMS). He continued his studies in the master’s programme in Process Engineering at TUHH, graduating at the end of 2023.

In 2024, Timo Merbach began working as a research assistant at the IMS, contributing to the Collaborative Research Centre (CRC) 1615 SMART Reactors and focusing on projects B04 and C01, which are dedicated to tailored transport processes in multiphase reactors and the integration of components into adaptive geometries. He is currently assigned to the working group Reactive Bubbly Flows due to the available expertise concerning transport processes in reactive systems.

Research

How are the different timescales of fluid dynamic mixing, mass transfer and reaction kinetics impacting the yield and selectivity of competitive-consecutive gas-liquid reactions?

Applying measuring techniques as Particle Image Velocimetry (PIV), Particle Tracking Velocimetry (PTV), Laser Induced Fluorescence (LIF) or imaging UV-VIS Spectroscopy to obtain information on velocity and concentration fields around reactive bubbles to understand the complex interplay of fluid dynamics, mass transfer and chemical reactions.

Education

Undergraduate courses

  • Grundlagen des Technischen Zeichnens (SoSe 2024)

  • Einführung in CAD (WiSe 2024/25)

  • Einführung in das Chemie- und Bioingenieurwesen (WiSe 2024/25)

Oral and Poster Presentations

Oral Presentations

  • Wigger. C., Merbach, T., Acikgöz, S., Herzog, D., Kelbassa, I., Schlüter, M., Weiland, C.: "Lagrangian Analysis of Reactive Flows Inside Porous Media using CFD", Jahrestreffen der DECHEMA/VDI-Fachgruppe CFD, Dresden, Germany, 2026, oral presentation
  • Wigger. C., Merbach, T., Weiland, C., Acikgöz, S., Herzog, D., von Kameke, A., Kelbassa, I., Schlüter, M.: "Identification and Characterisation of Heterogeneities in Triply Periodic Minimal Surface Structures using CFD", Multiscale Multiphase Process Engineering, Matsue, Japan, 2026, oral presentation
  • Merbach, T., Kexel, F., Nissen, J., Wigger, C., von Kameke, A., Schlüter, M.: "Optimizing Transport Processes in Vertically Aligned Carbon Nanotube Forests", International Conference on Multiphase Flow, Toulouse, France, 2025, oral presentation

  • Wigger C.; Merbach, T.; Weiland, C.; Acikgoez, S.; Herzog, D.; von Kameke, A.; Kelbassa, I.; Schlüter M.: "Identification and Characterisation of Stagnant Zones in Triply Periodic Minimal Surface Structures", Jahrestreffen der DECHEMA/VDI-Fachgruppen Mischvorgänge, Hochdruckverfahrenstechnik und Mehrphasenströmungen, Hamburg, Germany, 2025, oral presentation

Poster Presentations

  • Nissen, J., Merbach, T.; Kexel, F.; Schlüter, M., von Kameke, A.: "Transport Processes in Microchannels with fitted Carbon Nanotubes", Multiscale Multiphase Process Engineering, Matsue, Japan, 2026, poster presentation
  • Merbach, T.; Wigger, C.; Acikgoez, S.; Kexel, F.; Herzog, D.; Kelbassa, I.; Schlüter, M.: "Tailoring Multiscale Transport Phenomena through Hierarchical Structures for SMART Reactors", Jahrestreffen der DECHEMA/VDI-Fachgruppen Mischvorgänge, Hochdruckverfahrenstechnik und Mehrphasenströmungen, Hamburg, Germany, 2025, poster presentation 

  • Adrian, M.; Tsanda, A.; Merbach, T.; Acikgoez, S.; Herzog, D.; Benders, S.; Kelbassa, I.; Schlüter, M.; Knopp, T.; Penn, A.: "Advancing Multiphase Flow Imaging with High-Density Receiver Arrays: MRI Velocity Measurements in Structured Packing with Schwarz-Diamond-TPSf Design", Jahrestreffen der DECHEMA/VDI-Fachgruppen Mischvorgänge, Hochdruckverfahrenstechnik und Mehrphasenströmungen, Hamburg, Germany, 2025, poster presentation 

  • Merbach, T.; Mockus, B.; Minamitani, K.; Kexel, F.; Schlüter, M.; Valluri, P.; Hayashi, K.; Tomiyama, A.: "Development of a Correlation for the Terminal Rising Velocity for 2D-Bubbles in Unconfined Domain", 11th International Conference on Multiphase Flows, Kobe, Japan, 2023, poster presentation
  • Mockus, B.; Merbach, T.; Minamitani, K.; Valluri, P.; Schlüter, M.; Kurimoto, R.; Hayashi, K.; Tomiyama, A.: "Terminal Velocity and Mass Transfer of 2D Bubbles in a Confined Hele-Shaw Cell", 11th International Conference on Multiphase Flows, Kobe, Japan, 2023, poster presentation

  • Kexel, F.; Bertram, S.; Merbach, T.; von Kameke, A.; Hoffmann, M.; Tomiyama, A.; Schlüter, M.: "Influence of Taylor Bubble Shapes on Wake Structures", 4th International Symposium on Multiscale Multiphase Process Engineering, Berlin, 2022, poster presentation

Publications

[192117]
Title: Design guidelines for laser powder bed fusion of triply periodic minimal surface structures for applications in smart reactors.
Written by: Acikgöz, S.; Wigger, C.; Merbach, T.; Kexel, F.; Maiwald, M. I.; Herzog, D.; Kelbassa, I.; Schlüter M.
in: <em>Prog. Addit. Manuf</em>. January (2026).
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DOI: 10.1007/s40964-025-01457-y
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Abstract: Additive Manufacturing (AM), particularly Laser Powder Bed Fusion (PBF-LB/M), has transformed the production of complex metallic structures, enabling applications in smart reactors where enhanced heat and mass transfer at minimal pressure drop are critical. Triply Periodic Minimal Surface (TPMS) structures, such as Gyroid-TPSf and Schwarz-Diamond-TPSf geometries, offer unique advantages due to their high surface area-to-volume ratios, tunable porosity, and zero mean curvature. However, their manufacturability using PBF-LB/M remains underexplored, especially for demanding applications in process engineering that require structural integrity under extreme conditions. This study investigates the design and manufacturability of TPMS structures using 316L stainless steel via PBF-LB/M, focusing on the interaction of the key parameters porosity, unit cell size, and sheet thickness, of which two are independent variables while the third is a dependent variable. Through numerical simulations, experimental validation, and process optimization, practical design guidelines are developed. In this study, the design parameters of Gyroid-TPSf and Schwarz-Diamond-TPSf samples include porosities ranging from 70 to 90% and unit cell sizes from 2 to 20 mm. The results indicate that specifically, at large unit cell sizes (e.g., 20 mm), the decreased curvature radius reduces self-supporting effects, leading to insufficient mechanical stability during printing and resulting in local deformation. Conversely, at small unit cell sizes combined with high porosity levels (e.g., 2 mm and 90%), the sheet thickness becomes critically thin, often below the printable resolution, resulting in incomplete or fragile structures. CFD simulations were validated against experimental data across various volume flow rates. This work enables a knowledge-based selection of a suitable type of TPMS and its design parameters depending on the required flow characteristics in a given process engineering task while maintaining manufacturability. In conclusion, the study underscores the need for further refinement of design and manufacturing processes to fully exploit their benefits.