Recent developments in the modelling of heating and evaporation of spherical and non-spherical, mono- and multi-component droplets will be reviewed. The focus will be on simple models, compared with Direct Numerical Simulations, which, despite their simplicity, can capture the most significant features of the phenomena. For spherical droplets, these models are based on the analytical solutions to the one-dimensional heat transfer and component diffusion equations in a composite droplet. The analytical solutions to these equations were obtained, implemented into the numerical code, and used at each time step of the calculations.

The radiative heating of the droplet will be considered assuming that the droplet is semi-transparent. The effect of a supporting wire will be taken into account assuming that heat supplied from the wire is distributed instantaneously and homogeneously throughout the whole droplet volume.

A new model for mono-component droplet heating and evaporation will be reviewed. This model links the previously developed liquid phase model, using the analytical solution to the heat transfer equation at each time step, and the gas phase model, using the solution to the equations of the conservation of mass, momentum, and energy leading to an explicit expression for the Nusselt number and implicit expression for evaporation rate of the droplet. The latter expressions are used as boundary conditions for the liquid phase model. The new model was verified using a comparison between its predictions of the droplet temperatures and radii for very large liquid thermal conductivity and those of the model, using the assumption that the thermal conductivity of liquid is infinitely large. The closeness between the predictions of these models supports the reliability of both.

The model was validated using the experimental data obtained at the Heat and Mass Transfer laboratory of Tomsk Polytechnical University referring to the heating and evaporation of droplets. The deviations between the measured and predicted droplet radii and temperatures in most cases were shown to be within experimental error margins.

Greater integration of materials, product and processes of multi-components system is demanded ultimately toward a knowledge-based control of advanced manufacturing technologies. High-performance manufacturing (HPM) of product is a big challenge for integrated design and processing toward desired high performance due to highly ill-posed multi-objective optimization problem. A coupled design and processing modeling of product includes full finite element structural model of the system connected with manufacturing thermodynamics models of its components. The key components and their key processing/assembling processes identify on sensitivity analysis of accumulative surface integrity change in process chains and then in service under localized service conditions of components in data and model regularization of material-oriented regularization method. The system performance is determined by multiple components sum of accumulative surface integrity change under the localized service conditions allocated from the system service conditions. The manufacturing inverse problem to synergistically optimize the design and processing parameters is solved on sensitivity matrix algorithm with characteristic process signatures of the key components in the key process chains. A canned main coolant pump (MCP) prototype as a study case with the optimized geometry, materials and structure toward required dynamic performance is successfully manufactured in the optimized desigh and processing parameters by the additive manufacturing, near net shape manufacturing, joining/cladding, and surface modification/coating.   

High-flux solar irradiation obtained with optical concentrators is a viable source of clean process heat for high-temperature physical and chemical processing. Traditionally, the progress in concentrating solar thermal technologies has been driven by advancements in concentrated solar power, in particular in the context of large-scale dispatchable power generation. Solar thermochemistry is concerned with direct thermochemical production of chemical fuels and materials processing, without intermediate electricity generation, promising high energy conversion efficiency. In this presentation, recent advances in numerical modelling of multiphase transport phenomena in high-temperature solar thermal systems are discussed. Two types of multiphase flows recently investigated for efficient collection, conversion and storage of concentrated solar energy are focused on: (1) particle–gas flows featuring polydisperse particle transport under direct concentrated solar irradiation, and (2) boiling sodium flows. Governing equations and numerical solution methods are elaborated along with selected results obtained for free-falling particle and liquid sodium solar receivers. Examples of on-sun demonstration and pilot systems and the potential for improving the efficiency of solar energy collection, conversion and storage processes are discussed.

The talk presents the latest research developments in vortex flow methods for efficient heat transfer enhancement for gas turbine blade cooling in my research group at Shanghai Jiao Tong University in China. I will first present a fundamental study related to the vortex flow by various dimpled surfaces for heat transfer enhancement, and the intensified vortex flow by the rib turbulator and dimple hybrid structures for heat transfer enhancement in improving the rib turbulated cooling and the latticework matrix cooling for gas turbine blades. Furthermore, the vortex flow by the micro ribs on the surface is also studied for efficient heat transfer enhancement in jet impingement cooling. In an applied study, vortex flow control is achieved through novel guiding pin fins in wedged channel for improving the gas turbine blade trailing edge cooling.

Light, a phenomenon both enigmatic and ubiquitous throughout history, has captivated minds for centuries. Scientists and Engineers driven by technological advancements, managed to exploit light for developing a formidable source of coherent, monochromatic, collimated and high intensity photons: the LASER. In popular consciousness, LASER is often associated either with illuminating substances—laser pointers and laser scanners—or, much more frequently, as tools for destroying matter, from laser cutting machines for metal to laser guns in science fiction movies. Nowadays, LASER technology is extensively used both for industrial and research purposes. To this end, engineers and researchers work on optical additive technologies by using LASER enabling intricate manipulation of matter and allowing the reproduction of highly complex structures with impressive precision. For instance, two-photon polymerization enables us to create a replica of the Venus de Milo with micron and even submicron resolution.

An even more fascinating application of LASER is the ability to manipulate microscopic scale objects, known as optical tweezers (trapping) technology. Optical trapping is a non – invasive and non – destructive technology, which extends to the delicate control even of living cells without causing them any discomfort. Discoveries explaining and applying these phenomena have already been recognized with several Nobel Prizes in Physics: first in 1997 for the development of methods for laser cooling and trapping of atoms, for achieving Bose-Einstein condensation in 2001, for the first super-resolution microscope for single-molecule localization in 2014, and also for optical tweezers and their application in biological systems in 2018. In this introductory lecture, we will address the principles of optical tweezers, examining the key approximations for describing their operation. We will explore the principles of forming optical nanojets and the potential for integrating these technologies. Primarily, optical tweezers and LASER processing will be utilized to nanofunctionalize 2-D materials and implement highly precise direct laser spots. We will also attempt to answer questions such as whether it is possible to approach and surpass the diffraction limit in the precision of the technological process, which medium is more promising—liquid or gas, and whether liquid boiling during processing is a friend or foe. Answers to these questions will allow a better understanding of the nature of the involved technologies and confirm that solving the related physical and engineering challenges is largely connected to the engineering of thermophysics and physical hydrodynamics.

Kinetic helicity is defined as the correlation between the velocity field and its vorticity. Helicity, like energy, is an inviscid invariant of the equations of hydrodynamics. Unlike energy, which is a measure of turbulence intensity, helicity is a measure of vortex tube entanglement. The helicity effect can manifest itself both in the spectral transfer of turbulent energy between different scales and influencing the momentum flux in physical space caused by Reynolds stresses. The paper explains the physical significance of this effect and describes a mathematical model of helical turbulence. In addition to suppressing the transfer, inhomogeneous helicity in combination with rotation can cause large-scale flow. However, in the presence of external sources of small-scale helicity, a reverse energy cascade occurs even in the case of homogeneous and isotropic turbulence. The results of direct numerical modeling confirming the generation of a global flow under the influence of helicity will be considered, and some possible applications to phenomena in geophysical and astrophysical flows will be given.

Light, a phenomenon both enigmatic and ubiquitous throughout history, has captivated minds for centuries. Scientists and Engineers driven by technological advancements, managed to exploit light for developing a formidable source of coherent, monochromatic, collimated and high intensity photons: the LASER. In popular consciousness, LASER is often associated either with illuminating substances—laser pointers and laser scanners—or, much more frequently, as tools for destroying matter, from laser cutting machines for metal to laser guns in science fiction movies. Nowadays, LASER technology is extensively used both for industrial and research purposes. To this end, engineers and researchers work on optical additive technologies by using LASER enabling intricate manipulation of matter and allowing the reproduction of highly complex structures with impressive precision. For instance, two-photon polymerization enables us to create a replica of the Venus de Milo with micron and even submicron resolution.

An even more fascinating application of LASER is the ability to manipulate microscopic scale objects, known as optical tweezers (trapping) technology. Optical trapping is a non – invasive and non – destructive technology, which extends to the delicate control even of living cells without causing them any discomfort. Discoveries explaining and applying these phenomena have already been recognized with several Nobel Prizes in Physics: first in 1997 for the development of methods for laser cooling and trapping of atoms, for achieving Bose-Einstein condensation in 2001, for the first super-resolution microscope for single-molecule localization in 2014, and also for optical tweezers and their application in biological systems in 2018. In this introductory lecture, we will address the principles of optical tweezers, examining the key approximations for describing their operation. We will explore the principles of forming optical nanojets and the potential for integrating these technologies. Primarily, optical tweezers and LASER processing will be utilized to nanofunctionalize 2-D materials and implement highly precise direct laser spots. We will also attempt to answer questions such as whether it is possible to approach and surpass the diffraction limit in the precision of the technological process, which medium is more promising—liquid or gas, and whether liquid boiling during processing is a friend or foe. Answers to these questions will allow a better understanding of the nature of the involved technologies and confirm that solving the related physical and engineering challenges is largely connected to the engineering of thermophysics and physical hydrodynamics.

Boiling, cavitation, droplet condensation and freezing are considered as basic phase change phenomena. These phase change phenomena can be manipulated and controlled using surface modification as a passive method. One of the most promising approaches in surface modification include the use of modified surfaces with mixed wettability along the surface, which pay way to significant performance enhancements leading to energy savings. It is also possible to obtain optimized surface configurations depending on the operating condition and application as well as the phase change phenomenon. Such optimization efforts will make it possible to maximize energy savings and efficiency in thermal-fluids systems involving phase change and will further contribute to tackle with global warming. In this talk, our recent efforts and results in this topic will be presented and recent developments and trends in this field will be discussed.

The second part of the talk will focus on scalable and practical method for having the same effect of modified surfaces with surface enhancements via next generation bio-coatings based on hyperthermophilic archaea and antifreeze proteins, which could allow to have durable, environmentally friendly, inexpensive, and unique structures and to offer surface modification without the use of any cleanroom fabrication techniques. The results of studies on these new generation surfaces will be presented for boiling, dropwise condensation and freezing.

Light, a phenomenon both enigmatic and ubiquitous throughout history, has captivated minds for centuries. Scientists and Engineers driven by technological advancements, managed to exploit light for developing a formidable source of coherent, monochromatic, collimated and high intensity photons: the LASER. In popular consciousness, LASER is often associated either with illuminating substances—laser pointers and laser scanners—or, much more frequently, as tools for destroying matter, from laser cutting machines for metal to laser guns in science fiction movies. Nowadays, LASER technology is extensively used both for industrial and research purposes. To this end, engineers and researchers work on optical additive technologies by using LASER enabling intricate manipulation of matter and allowing the reproduction of highly complex structures with impressive precision. For instance, two-photon polymerization enables us to create a replica of the Venus de Milo with micron and even submicron resolution.

An even more fascinating application of LASER is the ability to manipulate microscopic scale objects, known as optical tweezers (trapping) technology. Optical trapping is a non – invasive and non – destructive technology, which extends to the delicate control even of living cells without causing them any discomfort. Discoveries explaining and applying these phenomena have already been recognized with several Nobel Prizes in Physics: first in 1997 for the development of methods for laser cooling and trapping of atoms, for achieving Bose-Einstein condensation in 2001, for the first super-resolution microscope for single-molecule localization in 2014, and also for optical tweezers and their application in biological systems in 2018. In this introductory lecture, we will address the principles of optical tweezers, examining the key approximations for describing their operation. We will explore the principles of forming optical nanojets and the potential for integrating these technologies. Primarily, optical tweezers and LASER processing will be utilized to nanofunctionalize 2-D materials and implement highly precise direct laser spots. We will also attempt to answer questions such as whether it is possible to approach and surpass the diffraction limit in the precision of the technological process, which medium is more promising—liquid or gas, and whether liquid boiling during processing is a friend or foe. Answers to these questions will allow a better understanding of the nature of the involved technologies and confirm that solving the related physical and engineering challenges is largely connected to the engineering of thermophysics and physical hydrodynamics.

Advanced and efficient energy saving and storage technologies play important roles to the fields of energy, power, petrochemical, metallurgy, refrigeration, aerospace and other fields. For energy systems, traditional design calculation often relies on the overall lumped parameter method, which will face problems such as hard to clearly show local characteristics and calculated difficulties in the analysis process. This report presents a thermal resistance regulation method, based on thermal resistance networks and thermoelectric analogy. The thermal resistance field is constructed by assigning the thermal resistance for discrete control units at points. From the energy transfer, the concept of multi-dimensional conduction-advection thermal resistance in parallel in fluid domain is proposed, and the conduction-advection thermal resistance network with heat capacity is constructed, which enables the integration of momentum and heat transfer in the fluid domain and explains the mechanism of local energy exchange. The relative relationship between thermal resistance and energy is investigated by order-of-magnitude analysis from the parallel thermal resistance analysis. Subsequently, based on analysing the relative magnitude of the thermal resistance distribution, a computational expression for the local thermal resistance is obtained. On this basis, typical heat transfer processes such as double-sided heat transfer are studied, and local thermal resistance analysis methods such as local thermal resistance ratio and local total thermal resistance are proposed. Afterwards, a large amount of data is further analyzed and fitted to construct a correlation equation between the local thermal resistance and the macroscopic parameters, which provides the means to guide the practical engineering applications. The conduction-advection parallel thermal resistance network is important to analyze the flow and heat transfer processes and guide the regulation and optimization of the heat transfer processes. The local thermal resistance method, on the other hand, achieves the accuracy of calculation and the simplicity of design from the computational heat transfer method, and provides the approach to realization for engineering applications. The thermal resistance adjustment principle based on the local thermal resistance method is an important guide for the accurate design of energy saving and storage devices.

The Siberian school of thermal physicists has made a significant contribution to the development of research in the field of convective heat transfer under complex conditions, near-wall turbulence and methods for controlling the intensity of heat and mass transfer processes. Almost from the day the Institute of Thermal Physics was founded, this area has become a priority and has been constantly given close attention. Such interest in the problems of convective heat and mass transfer was dictated by important applications in various fields of technology - power engineering, aerospace engineering, chemical technologies and many other energy-intensive devices and units. This direction was laid by S.S. Kutateladze together with A.I. Leontiev. They developed an asymptotic theory of a turbulent boundary layer based on the amazing properties of boundary layers with vanishing viscosity. The obtained relationships for the transfer coefficients under complex flow conditions (injection, suction, non-isothermality, compressibility, flow inhomogeneity, etc.) are striking in their simplicity and at the same time in the accuracy of prediction. Therefore, the methods of calculating the flow and heat exchange developed on the basis of the conclusions of the asymptotic theory have become very popular among practical engineers. Similar ideas were used in the development of methods for calculating the thermal protection of heat-stressed surfaces, which is also an important contribution of Siberian researchers to the theory and practice of heat exchange. Particular attention was paid to the development of new methods of thermophysical experiment, the creation of unique experimental stands, and methods for automating the collection and processing of measurement results. The report presents a retrospective of the development of research up to the present day. A wide range of topical problems is considered, which are currently being worked on by researchers of the IT SB RAS, such as control of heat exchange processes during forced and natural convection, heat exchange intensification, thermal protection, and much more.

The report will cover the following issues: the history of research into the phenomenon of superheating, starting from the first systematic works by the University of Toronto staff; the history of research carried out at the Ural School of Thermophysics, starting from the 1950s; modern methods and results of measuring the temperature of achievable superheating and the properties of superheated liquids and supercritical fluids under substantially non-stationary conditions; characteristic features of boiling of solutions with limited solubility of components having a lower critical solution temperature in the regions of not entirely stable (located above the liquid-liquid binodal and/or liquid-vapor binodal) and unstable (located above the liquid-liquid spinodal) states; promising, in the author's opinion, problems in the field of superheating of complex objects.