prof. Ing. Ivan Křupka, Ph.D.

1. A heat and mass transfer simulation tool for the primary cooling zone in continuous steel casting

   The thermal behaviour of steel in the mould - the primary cooling zone in continuous steel casting - has a substantial influence on the quality and properties of cast steel. However, due to the high computational cost, some phenomena are often neglected in simulation models for continuous steel casting. The work is focused on the development and implementation of a computer model for the primary and partially secondary cooling zone, which will take into consideration fluid flow of the melt, oscillations of the mould, and electromagnetic stirring. The topic is involved in a currently solved research project.

   Tutor: Klimeš Lubomír, doc. Ing., Ph.D.

2. Advanced mathematical methods for the solution of inverse heat transfer problems

   Computer simulations of engineering systems including heat and mass transfer often require the inverse determination of thermophysical properties and/or initial and boundary conditions from the transient thermal behaviour of such systems. The work is focused on the utilisation of advanced mathematical methods, e.g. neural networks and artificial intelligence, to the solution of inverse heat and mass transfer problems. The topic is involved in currently solved research projects (thermal energy storage and steelmaking), and another research project closely related to this topic is being prepared.

   Tutor: Klimeš Lubomír, doc. Ing., Ph.D.

3. Energy efficient twin-fluid atomizers for effective post combustion CO2 and NOx removal

   Ever increasing energy demands along with limited availability of alternative and renewable technologies requires using of fossil fuels in today’s world. Burning of fossil fuels for energy requirements results in emission of greenhouse flue gasses such as CO2 and NOx. Post combustion-capture of primary greenhouse gases is one of the methods reducing global warming. This project is focused on developing a twin-fluid atomizer for spraying of aqueous ammonia solutions which scrubs CO2 from flue gasses by chemical absorption process. Achieving fine spray with 50 μm mean diameter and a narrow drop size distribution is required for effective and controlled scrubbing process. Systematic study of suitability of air-assisted atomization methods with low atomizing gas consumption and advanced atomizer design are the primary objectives of the present project. Developing such an atomizer will allow in effective solvent utilization and reduce the operating costs of the flue gas scrubbing process. This atomizer will also find other applications requiring low atomizing gas consumption and high atomization efficiency. Detailed understanding of spray mixing and droplet-gas interactions in spray columns is critical for increasing efficiency and reducing ammonia slip in spray columns. The computational aspect supported by the experimental finding of this project is aimed to address this issue. The experimental data obtained during the project will form a data strong base for computational simulations of the scrubbing process. Computational models supported by sound experimental data will help in understanding the dynamics of liquid gas interaction and lead towards designing efficient spray columns for flue gas scrubbing. Collaboration between research groups in IIT Tirupati and Brno University Technology will help in exchanging the ideas in the area of liquid atomization and coming up with solutions for reducing global warming.

   Tutor: Jedelský Jan, prof. Ing., Ph.D.

4. Heat transfer and distribution strategies in energy systems of E-vehicles.

   The topic is focused on research of systems and methods ensuring heat transfer and distribution in electric vehicles. A closer focus will be on research into strategies for the transfer and distribution of heat generated by the operation of batteries and other systems in various vehicle operating conditions (driving, quick charging, normal charging, standing) and the use of this heat for other purposes (comfort cab services, etc.).

   Tutor: Jícha Miroslav, prof. Ing., CSc.

5. Liquid flow dynamics and its distribution in a rotating packed bed for CO2 capture

   By means of experiments and computational modelling to study impact of differently distributed liquid in a rotating bed, packed with porous structures (different knitted wire mesh) on liquid dispersion inside the bed. The rotating packed bed is aimed at generating high centrifugal force that contributes to a more intense liquid separation inside the bed and a formation of large interfacial surface between liquid and gas that counter-flows inside the wire mesh. The study will focus on different types of liquid distribution (nozzles with different size spectrum, different orientation, full, hollow, flat cone etc.) and the influence of number of rotation and centrifugal force on liquid dispersion inside the bed and/or on the correlation between characteristics of inlet liquid and outlet liquid phase from the rotating annulus. Based on these correlations an optimal liquid distribution on the internal rotating bed will be analysed.

   Tutor: Jícha Miroslav, prof. Ing., CSc.

6. Method for energy effective thermal management of car cabins

   The topic is focused on research and development of methods and procedures enabling optimal thermal management of the vehicles' cabin. The main control parameters will be based on the requirements for thermal comfort, heat / cold distribution, air quality, cabin services (defrost, defog) and active management of the technologies that provide these services. As the main experimental tool is supposed to use equipment and systems of laboratory of climatic chamber of the department OTTP, FSI.

   Tutor: Jícha Miroslav, prof. Ing., CSc.

7. Research of internal flow and spraying process of advanced designs of Spill-return pressure-swirl atomizers

   Motivation and Goals Spill-return pressure-swirl atomizers (SR PSAs) are wrongly forgotten devices suitable for spraying liquids under specific, nowadays emerging cases when a wide range of turn-down ratios, low pressures, high liquid viscosities or very low flowrates are required. They are not as studied as simplex atomizers namely in the application relevant conditions (elevated pressure, temperature, cross- or coo-flow). The quantification and characterization of the geometrical and kinematic (the displacement speed) characteristics of the gas-liquid interface during the spraying process remain an important challenge in the exploration of the internal flow, discharge and sheet formation, and primary/secondary atomization phenomena. The continuing advances in optical diagnostic methods as well as in CFD (computational fluid dynamics) simulations allow advancing our knowledge to a new level. The experiments performed under specific conditions require a modification of the present experimental infrastructure and improvement of the setup of optical diagnostic approaches along with development and validation of new methodologies for the data analysis and procedures to characterise the liquid-gas flows. The PhD study aims to elucidate the processes related to SR PSAs for application in combustion turbines (the internal flow and air core dynamics, spray stability and cone angle) and to explain the effect of realistic conditions on the spray development. The applicant will focus on several hypotheses, where no available data can be found, are insufficient, or contradictory conclusions were made by different authors: - The internal arrangement (spill-line configuration and shape of convergent part of the swirl chamber) affects the internal flow and formation of the liquid sheet outside the atomizer. - The presence of the external cross/coo-flow induces turbulence and affects the primary breakup distance of the liquid sheet and resulting spray quality. Approaches and methods The applicant will benefit from existing knowhow and methods developed in the Spray laboratory. The gas-liquid flow and interfaces will be tracked using a high-speed camera, image-based object sizing techniques and PIV algorithm. The flow field inside the atomizer and on the liquid film will be estimated by means of particle tracking, applying several assumptions and simplifications. Combination of the particle position/velocity measurement and the model assumptions allows to fully describe the particle kinematics and by tracking multiple particles to estimate the internal flow and to describe the entire flow field. Doppler-based methods will give direct quantitative data on the velocity and size of particles. The advanced experiments supported with CFD simulations and analytical approaches will be used to find out the properties of the internal flow and spray and allow a better understanding of the coupling between interface velocity and geometry. Note: The experimental equipment is available at the Department of Thermomechanics and Environmental engineering, EU FSI. The student will provide the PhD study in the frame of the research projects of specific research, basic research projects of the Czech science foundation, etc.

   Tutor: Jedelský Jan, prof. Ing., Ph.D.