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Chemical and Process Engineering
Doctoral Programme,
Faculty of Chemical Engineering
--- Careers--- Programme Details
Ph.D. topics for study year 2026/27Diagnostics of two-phase flows in microchannels
AnnotationThe aim of this project is to experimentally investigate the character of two-phase (gas/liquid) flow in microchannels. The mapping of different flow regimes will be performed for different microchannel configurations (e.g., channel crossing, T-junction, sudden expansion) and different model fluids (Newtonian, viscoelastic, pseudoplastic). The electrodiffusion method, an original experimental technique developed in our department, is used to determine the liquid flow in the near-wall region and to detect the characteristics of translating bubbles. The visualization experiments with a high-speed camera and the velocity field measurements with the mPIV technique will provide additional information about the flow structure in microchannels. The candidate should have a Master's degree in chemical engineering or a similar applied science field. He/she should have experimental skills for laboratory work and some basic knowledge of hydrodynamics. However, enthusiasm for independent scientific work is the most important requirement. The candidate will certainly benefit from our long experience in experimental (computer-controlled measurements with subsequent data processing in LabView) and theoretical (solving complex hydrodynamic problems in MatLab or Mathematica) fluid mechanics. Consistent bridging of particle-resolved and semi-resolved simulations of particle-laden flows
AnnotationThe Ph.D. thesis focuses on the development of a consistent multiscale methodology that bridges particle-resolved and semi-resolved simulations of particle-laden flows. Motivated by the severe computational limitations of fully resolved CFD–DEM approaches and the insufficient physical fidelity of conventional semi-resolved models, the work aims to establish a scale-aware framework that enables accurate and computationally efficient simulations across a wide range of particle concentrations, sizes, and shapes. We build on an existing particle-resolved CFD–DEM solver capable of handling arbitrarily shaped particles. From simulations evaluated using the aforementioned solver, physically consistent closure information are systematically extracted, in particular hydrodynamic interaction forces such as drag and lift. These data are then used to construct surrogate models based on artificial neural networks, allowing the essential microscale physics to be embedded into semi-resolved formulations without explicitly resolving the flow around each particle. Emphasis is placed on numerical consistency, robustness, and transferability across flow regimes, particle morphologies, and solid phase volume fractions. Mathematical modelling of polymerization processes
AnnotationTéma je zaměřeno na vývoj pokročilých matematických modelů poylmerizačních i depolymerizačních reakcí souvisejících s rozličnými, průmyslově motivovanými problémy, např. cílenou depolymerizací hyaluronanů termální hydrolýzou, polymerací ethylénu za vysokého tlaku či Fischer-Tropschovou syntézou jakožto možnou alternativou pro výrobu syntetických paliv. Motivace jednotlivých případových studií bude jednak zlepšení vlastností finálního produktu, jednak vývoj prediktivních systémů pro zajištění bezpečnosti průmyslových procesů. Práce bude založena jednak na "first-principles" deterministickém modelování reakčně-transportních jevů, ale využita bude také metodika kontinuace ustálených stavů pro analýzu stability řešení. Vyvinuté modely budou posléze ve spolupráci se zahraničními partnery integrovány do většího celku zahrnujícího i "data-driven" statistické modely založené na principech strojového učení. Microbubbles: formation, properties, applications
AnnotationMicrobubbles are small gas bubbles (approximately 1-1000 microns in size) dispersed in a liquid. In many respects, they behave differently from 'normal' bubbles measuring millimeters and centimeters, which are used in most multiphase devices (contactors, reactors). They have a low rising velocity and thus a long delay time, which improves transport and reaction processes and reduces waste. They have a large specific surface area (m2)/(m3) for a given volume of gas in the device. They are increasingly used in various applications, but still their behaviour under complex industrial conditions is not fully understood. In this dissertation, the student will learn the basic skills of working with microbubbles, such as their preparation using microbubble generators and the characterization of their basic properties. They will then solve a given project involving their specific use in a process or application. The project topic will be assigned by agreement, depending on current opportunities and possibilities. The knowledge gained will be applicable in various types of industrial applications (chemical, biotechnological, food, metallurgical, pharmaceutical, environmental, etc.). Requirements • Master degree, in chemical engineering or a related field, creative approach to research, and teamwork ability. Preparation of a microfluidic platform for diagnostics
AnnotationSeparation of organic vapors and gases with tailored membranes
AnnotationMetal/covalent organic frameworks, as well as functionalized nanostructure materials with ionic liquids, are advancing the separation capabilities of polymer membranes for gas and organic vapor separations. Such functionalization of membranes also suppresses negative phenomena, such as plasticization and aging, which limit the use of a new generation of polymeric materials with excellent separation properties. This work aims to investigate the effect of the type and amount of functionalization on the transport-separation parameters and the structure of membranes. The study of the transport and separation properties will be carried out using automated systems to measure the permeation of gas and organic vapor mixtures. Also, the possibilities of predicting transport parameters using physical models and machine learning methods will be explored. Required education and skills: • Master's degree in Chemical Engineering, Physical Chemistry, or any relevant field; • interest in science, willingness for experimental work, and to learn new things; teamwork ability. Structured catalytic reactors for industrial applications
AnnotationPráce se věnuje experimentálnímu vývoji strukturovaných katalytických reaktorů pro průmyslové aplikace, jako jsou ukládání a uvolňování energie ve formě bezuhlíkatých paliv (NH3, H2 a další), jejich využití v palivových článcích a také katalytické odstraňování škodlivin z výfukových plynů. Ve středu zájmu jsou reakční kinetika katalytických reakcí a dále zlepšení přenosu hmoty a tepla v reaktoru pro dosažení co nejvyšší konverze. Flow Based Evaluation of Light Activated Antibacterial Surfaces
AnnotationLight activated photocatalytic materials are attracting increasing interest as antibacterial surfaces because they can inactivate microorganisms upon illumination without the need for chemical disinfectants. However, their antibacterial performance is often studied under static or poorly controlled conditions, which makes it difficult to understand how and why they work and to transfer them to practical applications. In particular, the effects of flow conditions, mass transfer, and surface interactions are still not well understood. This PhD project focuses on studying antibacterial photocatalytic surfaces under well controlled flow conditions using microfluidic reactors. Bacteria will be exposed to reactive oxygen species generated at illuminated solid surfaces while key parameters such as reactor geometry, flow rate, residence time, and surface properties are systematically varied. This approach will allow the student to quantify bacterial inactivation and to understand the roles of transport and surface reactivity. Bacteria are used as simple test systems to evaluate surface performance, enabling the development of clear structure performance relationships and practical design guidelines for light activated antibacterial surfaces. The PhD topic is part of a project funded by the Czech Grant Agency and is carried out in cooperation with three major Czech research institutions, namely Brno University of Technology, Masaryk University, and the Czech Academy of Sciences. The outcomes of the project are relevant for flow based disinfection, water treatment, and related environmental applications. Heat transfer in granular materials during mechanical mixing
AnnotationThe PhD project focuses on the relationship between particle contact dynamics and heat transfer in mixed granular systems. Using a combination of the discrete element method (DEM), CFD simulations, and experiments in a rotating drum and vertical mixer, the study will investigate how the type and intensity of mixing affect the dominant mechanisms of heat transport. The aim is to link microscopic contact mechanics with the macroscopic thermal behavior of the system. Required education and skills • Master's degree in chemical engineering, mathematical modeling, and computer science; • high motivation, willingness to learn new things; • team spirit. Multiscale mathematical modeling of structured catalytic reactors and fuel cells
AnnotationPráce se věnuje víceúrovňovému matematickému modelování strukturovaných katalytických reaktorů a palivových článků pro průmyslové aplikace, jako jsou ukládání a uvolňování energie ve formě bezuhlíkatých paliv (NH3, H2 a další) a také katalytické odstraňování škodlivin z výfukových plynů. Ve středu zájmu jsou reakční kinetika katalytických reakcí a dále zlepšení přenosu hmoty a tepla v reaktoru pro dosažení co nejvyšší účinnosti a konverze. Vyvíjené modely pokrývají měřítka od mikroskopických porézních struktur až po celé zařízení. Effect of adhesion on granular dynamics and segregation during mixing
AnnotationThe PhD project focuses on the role of adhesion in the behavior of granular systems during mechanical mixing. Using the discrete element method (DEM) with cohesive contact models (JKR, bond model) and experimental validation, the study will investigate how adhesion influences segregation patterns and the dynamics of agglomerate formation and breakup. The aim is to understand under what conditions and in what ways adhesion modifies segregation, and what factors determine agglomerate stability under mechanical stress. Required education and skills • Master's degree in chemical engineering, mathematical modeling, and computer science; • high motivation, willingness to learn new things; • team spirit. Effect of interfacial properties on dynamics of bubbles
AnnotationMultiphase systems consisting of a gas phase dispersed in a liquid environment are omnipresent in nature and in living systems. Gas-liquid contact is also responsible for the success of many industrial processes, such as flotation, or aerated reactors. Surfactants, SAS, with their ability to lower the interfacial tension between gas-liquid phases, alter the behavior of many multiphase processes, and for many systems, the characterization of the interface by surface tension alone is not enough and less conventional measurements of surface rheology and SAS adsorption/desorption characteristics are crucial. The aim of this work is to determine experimentally the influence of surfactants on the dynamics of processes with bubbles (movement, dissolution, coalescence, etc.) and to characterize selected SASs by measuring relevant physico-chemical and transport properties. The typical work will include measurements of interfacial rheology, observation and evaluation of bubble dynamics by high-speed camera, and physical interpretation of results. Required education and skills • Master degree in chemical or mechanical engineering or in physical chemistry; • Systematic and creative approach to scientific research, teamwork ability. High-Throughput Experimentation for Heterogeneous Catalysis in Flow Reactors
AnnotationThis project aims to develop a platform combining high-throughput experimentation (HTE) with flow photomicroreactors to create efficient, scalable, and green heterogeneous catalytic processes. Addressing the complexity of catalytic reactions, varying catalysts, substrates, and reaction conditions, requires moving beyond traditional one-variable-at-a-time methods. HTE enables rapid screening of heterogeneous photocatalysts and reaction conditions across diverse photochemical transformations, while translating these reactions into flow photomicroreactors reduces reaction times, improves mass and photon transport, and accelerates discovery. The student will design experimental workflows integrating segmented flow in microreactors, where individual reaction parameters are tested in discrete liquid slugs containing suspended or immobilized solid catalysts, enabling systematic exploration of the reaction design space. HTE in the flow photomicroreactor will be coupled with in-line analytical techniques to distinguish effective and ineffective catalyst–substrate interactions. The resulting datasets will be visualized as heat maps, providing clear insight into structure and performance relationships and guiding rational optimization of heterogeneous catalytic systems. Development of advanced mathematical models for control of catalytic reactors
AnnotationPráce se věnuje vývoji matematických modelů pro účinné řízení provozu katalytických reaktorů v průmyslových aplikacích, jako jsou odstraňování škodlivin z výfukových plynů (systém pro selektivní katalytickou redukci NOx se vstřikováním močoviny), palivové články využívající bezuhlíkatých paliv (NH3, H2) a další. Vyvinuté modely musí být schopny v reálném čase popsat a předpovídat budoucí chování daného reaktoru na základě jeho historie a signálů z měřicích čidel. Bude zkoumán jak přístup pomocí klasických fyzikálně-chemických modelů, tak i s využitím modelů strojového učení a umělé inteligence. |
Updated: 20.1.2022 16:26, Author: Jan Kříž