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Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des fluides, Fluid dynamics, Stabilité hydrodynamique, Hydrodynamic stability, Instabilité sous l'effet de la poussée hydrostatique, Buoyancy-driven instability, Champ écoulement, Flow pattern, Convection cellulaire, Cellular convection, Convección celular, Couche liquide, Liquid layer, Capa líquida, Etude expérimentale, Experimental study, Force centrifuge, Centrifugal force, Instabilité Rayleigh Bénard, Rayleigh-Benard instability, Simulation numérique, Digital simulation, Système tournant, Rotating system, Sistema giratorio, Transfert chaleur, and Heat transfer

The structure of flow and heat exchange in a horizontal, heated from below, layer of liquid whose boundaries can rotate with the same and different angular velocities have been studied numerically and experimentally. The relative role of buoyancy and centrifugal forces in the formation of the flow structure of liquids with Pr = 16 and 2700 was investigated.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des fluides, Fluid dynamics, Stabilité hydrodynamique, Hydrodynamic stability, Instabilité sous l'effet de la tension superficielle, Surface-tension-driven instability, Champ température, Temperature distribution, Condition aux limites, Boundary conditions, Couche liquide, Liquid layer, Capa líquida, Distribution vitesse, Velocity distribution, Ecoulement cavité, Cavity flow, Flujo cavidad, Etude expérimentale, Experimental study, Instabilité convective, Convective instabilities, Simulation numérique, Digital simulation, Thermocapillarité, Thermocapillarity, Termocapilaridad, Transfert chaleur, and Heat transfer

Convective heat exchange in a flow of liquid in a rectangular cavity with the length-to-height ratio of a liquid layer L/H = 10 is investigated. The conditions of thermal insulation or linear distribution of temperature were kept on the lower horizontal surface. Three types of boundary conditions for velocity were set on the upper boundary: rigid, free without friction, and free with imposition of a thermocapillary effect. The vertical walls of the cavity are isothermal and heated to different temperatures. The investigated regimes were of thermogravitational, thermocapillary, and thermal gravitational-capillary convection. A comparative analysis of the evolution of flow structure with increase in the Rayleigh (Ra) and Marangoni (Ma) numbers is carried out.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Dispositifs d'utilisation de l'énergie thermique, Devices using thermal energy, Séchoirs, Dryers, Champ température, Temperature distribution, Campo temperatura, Humidité, Humidity, Humedad, Section isotherme, Isothermal section, Sección isotérmica, Séchage, Drying, Secado, Transfert chaleur, Heat transfer, Transferencia térmica, Transfert humidité, Humidity transfer, Transferencia húmeda, Transfert masse, Mass transfer, and Transferencia masa

The problem of contact drying of a layer of moist material placed on a hot isothermal surface is considered. A system of heat and mass transfer equations and equations for the initial and boundary conditions are proposed. Luikov's theoretical approach is utilized, but all relevant thermophysical coefficients are considered to be fully dependent on the temperature and moisture content inside the material during the process. The model is solved numerically. Results for temperature and moisture distributions inside the layer of the material obtained using this model are compared to results obtained by solving a model with constant thermophysical coefficients in the governing equations, formed by using the same type of heat and mass transfer equations and equations for the initial and boundary conditions. The process is also examined experimentally, which provided results that enable verification of the proposed models.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Etudes théoriques. Données et constantes. Mesures, Theoretical studies. Data and constants. Metering, Transfert de chaleur, Heat transfer, Autoorganisation, Self organization, Autoorganización, Equation non linéaire, Non linear equation, Ecuación no lineal, Equation parabolique, Parabolic equation, Ecuación parabólica, Instabilité hydrodynamique, Hydrodynamic instability, Inestabilidad hidrodinámica, Paquet onde, Wave packet, Paquete onda, Réaction chimique, Chemical reaction, Reacción química, Simulation numérique, Numerical simulation, Simulación numérica, Système chaotique, Chaotic systems, Transfert chaleur masse, Heat mass transfer, Transferencia calor masa, Turbulence, and Turbulencia

Nonlinear phenomena in thermophysical and chemical-technology processes are considered in the context of nonlinearity, instability, nonuniqueness, nonstationarity, and irreversibility. The perturbation frequency (phase)-to-amplitude ratio is the governing parameter of the nonlinear interaction of perturbations that are described by the proposed general nonlinear parabolic equation. The nonlinearity of this ratio characterizes turbulence, while its linearity characterizes self-organization. It is shown that chaotic conditions can be self-organized under the action of white noise, which favors the system getting into the domain of attraction of a stable node. The mechanism of the occurrence of turbulence is substantiated.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Généralités. Techniques, General aspects. Techniques, Méthodes et techniques (échantillonnage, marquage, piégeage, modélisation...), Methods and techniques (sampling, tagging, trapping, modelling...), Ecologie animale et végétale, Animal and plant ecology, Synécologie, Synecology, Ecosystèmes terrestres, Terrestrial ecosystems, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Accidents climatiques. Feux de végétation, Weather damages. Fires, Feux de végétation, Forest and land fires, Biométéorologie, Biometeorology, Biometeorología, Biophysique, Biophysics, Biofísica, Ecologie, Ecology, Ecología, Environnement, Environment, Medio ambiente, Foresterie, Forestry, Ciencias forestales, Physique appliquée, Applied physics, Física aplicada, Thermodynamique, Thermodynamics, Termodinámica, Combustible, Fuel, Dessiccation, Desiccation, Desecación, Etude expérimentale, Experimental study, Estudio experimental, Etude sur modèle, Model study, Estudio sobre modelo, Etude théorique, Theoretical study, Estudio teórico, Incendie forêt, Forest fire, Incendio forestal, Litière, Litter, Hojarasca, Matériau organique, Organic material, Material orgánico, Origine végétale, Plant origin, Origen vegetal, Problème mixte, Mixed problem, Problema mixto, Coniferales, Ecoulement air, Equation couche limite, Essai soufflerie, Evaporation, Feuille végétal, Matériau forestier combustible, Modèle couche, Modèle mathématique, Modèle physique, Modélisation, Pinus, Pluie, Précipitation atmosphérique, Rayonnement solaire, Transfert chaleur, Transfert humidité, Transfert masse, and Vitesse vent

Physical and mathematical modeling of drying of a layer of combustible forest materials (CFMs) is considered in a conjugate formulation within the framework of which the equations of a binary boundary layer and the equations of heat and mass transfer in a layer of combustible forest materials are solved. Boundary conditions for the laws of conservation of mass and energy are written on the interface of media. It is found experimentally and theoretically that the velocities of the flow and radiation strongly affect the time of drying of a layer of combustible forest materials, whereas the effect of the angle of inclination (slope) between the underlying surface and the horizontal plane is insignificant.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des fluides, Fluid dynamics, Mécanique des fluides appliquée, Applied fluid mechanics, Machines hydrauliques et pneumatiques, Hydraulic and pneumatic machinery, Aube turbine, Turbine blades, Bulle décollement, Separation bubble, Burbuja desprendimiento, Cascade profil, Aerofoil cascade, Cascada perfil, Distribution pression, Pressure distribution, Distribución presión, Distribution vitesse, Velocity distribution, Ecoulement tridimensionnel, Three dimensional flow, Flujo tridimensional, Etude comparative, Comparative study, Estudio comparativo, Génération maille, Mesh generation, Jeu mécanique, Mechanical clearance, Juego mecánico, Simulation numérique, Digital simulation, Tourbillon extrémité, End vortex, Torbellino extremidad, Turbomachine, Turbomachinery, Visualisation écoulement, and Flow visualization

Numerical analysis of the three-dimensional flow fields in an annual cascade with tip clearance and rotation and in a linear cascade is carried out. A comparison with flow visualization verifies the computational result. The comparison indicates that the numerical analysis captures the separation on the tip edge of the pressure side of the blade and the flow direction over the tip surface. However, it does not properly indicate the separation on the leading edge of the suction side. Rotation weakens the leakage flow so that the size of the separation bubble decreases on the tip surface. Large tip clearance increases leakage flow so that the tip vortex is larger and moves to the suction side.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Etudes théoriques. Données et constantes. Mesures, Theoretical studies. Data and constants. Metering, Transfert de chaleur, Heat transfer, Dispositifs d'utilisation de l'énergie thermique, Devices using thermal energy, Echangeurs de chaleur (y compris transformateurs de chaleur, tours de refroidissement, condenseurs), Heat exchangers (included heat transformers, condensers, cooling towers), Echangeur chaleur, Heat exchanger, Intercambiador calor, Echangeur tubulaire, Tubular heat exchanger, Intercambiador tubular, Ecoulement diphasique, Two phase flow, Flujo difásico, Ecoulement gaz liquide, Gas liquid flow, Flujo gas líquido, Faisceau tube, Tube bundle, Haz tubos, Transfert chaleur, Heat transfer, Transferencia térmica, Tube ailette, Finned tube, and Tubo con aletas

The current achievements in the field of intensification of heat exchange in tube heat-exchange apparatus are considered. Requirements for high-efficiency heat-transfer surfaces have been formulated. Problems of intensification of heat exchange in bundles of finned tubes and in heat-exchange apparatus under conditions of condensation and boiling of heat-transfer agents and under scaling conditions have been investigated. High-efficiency designs of heat-exchange apparatus are presented.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Pollution, Pollution atmosphérique, Atmospheric pollution, Etude de la physicochimie des polluants: propriétés, effets, réactions, transport et distribution, Pollutants physicochemistry study: properties, effects, reactions, transport and distribution, Aérosol, Aerosols, Aerosol, Centrale nucléaire, Nuclear power plant, Central nuclear, Centrale(production énergie), Power plant, Central eléctrica, Convection, Convección, Devenir polluant, Pollutant behavior, Evolución contaminante, Dispersion atmosphérique, Atmospheric dispersion, Dispersión atmosférica, Effet milieu, Medium effect, Efecto medio, Emission gaz, Gas emission, Emisión gas, Emission polluant, Pollutant emission, Emisión contaminante, Gaz chaud, Hot gas, Gas caliente, Gouttelette, Droplet, Gotita, Installation ventilation, Ventilating equipment, Instalación ventilación, Modélisation, Modeling, Modelización, Panache, Plume, Penacho, Particule en suspension, Suspended particle, Partícula en suspensión, Phénomène transport, Transport process, Fenómeno transporte, Pollution air, Air pollution, Contaminación aire, Tour refroidissement, Cooling tower, Torre enfriamiento, Transfert chaleur masse, Heat mass transfer, Transferencia calor masa, Vapeur eau, Water vapor, and Vapor agua

The sources of possible technogenic pollution of the atmosphere near power units are discussed. A procedure for evaluating the interaction of cooling-tower plumes with technogenic discharges of power units and with other pollutants of the atmosphere is presented. Results of a series of computational experiments as applied to an analysis of the action of the discharges of cooling towers on the aerosol discharges of ventilation systems of nuclear power plants (NPPs) are reported.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Pollution, Traitement et pollution des eaux, Water treatment and pollution, Pollution des eaux naturelles, Natural water pollution, Eaux continentales superficielles, Continental surface waters, Terre, ocean, espace, Earth, ocean, space, Sciences de la terre, Earth sciences, Géologie de l'ingénieur et de l'environnement. Géothermie, Engineering and environment geology. Geothermics, Pollution, géologie de l'environnement, Pollution, environment geology, Convection, Convección, Cours eau, Stream, Curso agua, Césium 137, Cesium 137, Devenir polluant, Pollutant behavior, Evolución contaminante, Eau surface, Surface water, Agua superficie, Etude cas, Case study, Estudio caso, Migration, Migración, Modèle compartimental, Compartmental model, Modelo compartimental, Modélisation, Modeling, Modelización, Particule en suspension, Suspended particle, Partícula en suspensión, Phénomène transport, Transport process, Fenómeno transporte, Pollution eau, Water pollution, Contaminación agua, Pollution radioactive, Radioactive pollution, Polución radioactiva, Radioisotope, Radionúclido, Simulation numérique, Numerical simulation, Simulación numérica, Strontium 90, Sédiment, Sediments, Sedimento, Transfert masse, Mass transfer, and Transferencia masa

The authors suggest a model of transfer of radionuclides in a river system, which relies on the principle of the chamber model, for the case of hydraulically stationary and chemically equilibrium conditions of interaction of radionuclides in the systems water-suspensions and water-bottom sediments. The model is based on analytical solutions of a system of equations for different conditions of ingress of radioactive contaminants into the river system: in the inlet cross section; with fallout of radiactive aerosols on the water surface; with ingress of radionuclides with surface flow from a contaminated water catchment. The model is verified using the data of radiation monitoring carried out on an experimental water catchment of the Iput river.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Transfert de chaleur, Heat transfer, Rayonnement thermique, Thermal radiation, Champ température, Temperature distribution, Chauffe, Heating, Cinétique, Kinetics, Diffusion lumière, Light scattering, Irradiation pulsée, Pulsed irradiation, Milieu gris, Gray medium, Medio gris, Rayonnement thermique, Thermal radiation, Refroidissement, Cooling, Simulation numérique, Digital simulation, Transfert radiatif, and Radiative transfer

The process of heating and cooling down of a light-scattering and absorbing plane-parallel layer irradiated by a light pulse is discussed. Results are obtained by solving numerically the differential equations of radiation transfer and heat conduction. By the method of finite-difference approximation of space derivatives the problem is reduced to a system of ordinary differential equations with respect to time for the temperature at each point of the layer. Results of calculations for different durations and powers of pulses and different optical and thermophysical parameters of the medium are reported. A comparison is made of the characteristics of temperature processes in the layer on the source side of incidence of a light pulse and on the opposite side.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Etudes théoriques. Données et constantes. Mesures, Theoretical studies. Data and constants. Metering, Etudes thermodynamiques, mécaniques etc. Appliquées à l'énergie, Thermodynamics, mechanics etc. For energy applications, Combustion, Combustión, Hydrodynamique, Hydrodynamics, Hidrodinámica, Recherche scientifique, Scientific research, Investigación científica, Réacteur nucléaire, Nuclear reactor, Reactor nuclear, Thermohydraulique, Thermohydraulics, Termohidraúlica, Transfert chaleur, Heat transfer, and Transferencia térmica

Consideration is given to the general features of fundamental thermophysical and hydrodynamic investigations carried out at scientific centers of the Lithuanian Republic. They are concentrated on the study of mixed convection and thermogravitation, processes of transfer as applied to the safety of nuclear reactors, processes of combustion in boilers, thermohydraulic processes in films and cooling basins, heat and mass exchange in two-phase systems of statically stable foams, processes of evaporation of dispersed bodies in complex systems, and issues of civil-engineering thermophysics.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Dispositifs d'utilisation de l'énergie thermique, Devices using thermal energy, Séchoirs, Dryers, Distribution dimension particule, Particle size distribution, Distribución dimensión partícula, Ecoulement tourbillonnaire, Swirling flow, Flujo torbellinal, Elément pneumatique, Pneumatic element, Elemento neumático, Etude expérimentale, Experimental study, Estudio experimental, Gouttelette, Droplet, Gotita, Générateur tourbillon, Vortex generator, Generador torbellino, Hydrodynamique, Hydrodynamics, Hidrodinámica, Séchage pulvérisation, Spray drying, Secado pulverización, Séchage, Drying, and Secado

Results of experimental investigations of the hydrodynamics of vortex pneumatic sprayers are discussed.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Aérosols, Aerosols, Amas, Cluster, Montón, Aérosol, Aerosols, Aerosol, Condensation, Condensación, Croissance, Growth, Crecimiento, Etude théorique, Theoretical study, Estudio teórico, Mélange gaz, Gas mixture, Mezcla gas, Nucléation, Nucleation, and Nucleación

The influence of a buffer (admixture) gas on the deposition of molecules of a vapor on particles of an aerosol system is investigated.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Pollution, Déchets, Wastes, Déchets de l'agriculture, de l'élevage, des industries agricoles et alimentaires, Agriculture, rearing and food industries wastes, Analyse chimique, Chemical analysis, Análisis químico, Arc électrique, Electric arc, Arco eléctrico, Composition chimique, Chemical composition, Composición química, Condition opératoire, Operating conditions, Condición operatoria, Déchet industriel, Industrial waste, Desperdicio industrial, Dégradation thermique, Thermal degradation, Degradación térmica, Effluent gazeux, Gaseous effluent, Efluente gaseoso, Etude expérimentale, Experimental study, Estudio experimental, Industrie agricole, Agricultural industry, Industria agrícola, Jet plasma, Plasma jet, Chorro plasma, Pesticide, Pesticides, Plaguicida, Produit agrochimique, Agricultural chemical product, Producto químico agrícola, Réacteur plasma, Plasma reactor, Reactor plasma, Traitement déchet, Waste treatment, Tratamiento desperdicios, Traitement thermique, Heat treatment, Tratamiento térmico, Transfert chaleur, Heat transfer, and Transferencia térmica

The possibility of using a multijet electric-arc plasma-chemical reactor for decontamination and destruction of different powder pesticides with an expired effective date and storage life which have not been used in agriculture is studied. Studies of heat transfer are conducted on a setup operating without processing of raw material and with supply of pesticides (isophen and butyl ester of 2,4-dichlorophenoxyacetic acid) to the reactor. The composition of waste gases at the reactor outlet is studied.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Etudes théoriques. Données et constantes. Mesures, Theoretical studies. Data and constants. Metering, Transfert de chaleur, Heat transfer, Champ température, Temperature distribution, Campo temperatura, Cylindre, Cylinder, Cilindro, Distribution vitesse, Velocity distribution, Distribución velocidad, Ecoulement conduite, Pipe flow, Flujo conducción, Ecoulement non isotherme, Non isothermal flow, Flujo no isotermo, Etirage, Drawing, Estiramiento, Modélisation, Modeling, Modelización, Refroidissement convection, Convection cooling, Enfriamiento convección, Refroidissement rayonnement, Radiation cooling, Enfriamiento radiación, Transfert chaleur masse, Heat mass transfer, and Transferencia calor masa

Heat transfer in stabilized regimes of non isothermal flows in a round tube and in channels with two-dimensional convex cross sections is investigated with allowance for the velocity profile of a heating or cooling flow of a fluid. Mathematical models of unsteady processes of cooling by convection and radiation in pulling of rods and plane sheets at a constant velocity and of heat transfer (mass transfer) in a thin running-down layer of a medium (fluid) are solved.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de croissance cristalline; physique de la croissance cristalline, Methods of crystal growth; physics of crystal growth, Croissance en phase fondue; fusion de zone et purification de zone, Growth from melts; zone melting and refining, Convection mixte, Combined convection, Convección mixta, Convection naturelle, Natural convection, Croissance cristalline en phase fondue, Crystal growth from melts, Etude expérimentale, Experimental study, Ligne courant, Streamlines, Méthode Czochralski, Czochralski method, Méthode différence finie, Finite difference method, Régime écoulement, Flow regime, Régimen flujo, Simulation numérique, Digital simulation, Thermocapillarité, Thermocapillarity, Termocapilaridad, Transfert chaleur, and Heat transfer

Numerically, by the method of finite differences, we investigated the regimes of laminar convection of a thermogravitational, thermocapillary, and gravitational-capillary nature in the classical variant of the Czochralski method. Evolution of the spatial form of flow in each type of convection and the trends of local and integral heat exchange in the range of Grashof, 0 ≤ Gr ≤ 8.104, and Marangoni, 0 ≤ Ma ≤ 6.5.104 numbers have studied for the Prandtl number Pr = 16. Local heat exchange in the regimes of free and mixed convection is investigated experimentally.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Terre, ocean, espace, Earth, ocean, space, Sciences de la terre, Earth sciences, Géologie de l'ingénieur et de l'environnement. Géothermie, Engineering and environment geology. Geothermics, Risques naturels: prévisions, dommages, etc, Natural hazards: prediction, damages, etc, Catastrophe naturelle, natural disasters, Catástrofe natural, Modèle mathématique, mathematical models, Modelo matemático, Probabilité, probability, Probabilidad, Propriété mécanique, mechanical properties, Propiedad mecánica, Prévision, prediction, Previsión, Risque naturel, Natural hazards, Riesgo natural, Théorie, theory, Teoría, Transfert chaleur, heat transfer, Transferencia térmica, Transfert masse, mass transfer, and Transferencia masa

Basic definitions and concepts of the physicomathematical theory of natural catastrophes are given. Possibilities of mathematical modeling of natural and technogenic catastrophes are discussed in the context of the theory of heat and mass transfer and the mechanics of reacting media. The importance of taking into account conjugate heat and mass exchange in modeling catastrophes is emphasized. A formula for evaluating the probability of a collisional catastrophe is given.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Synécologie, Synecology, Ecosystèmes terrestres, Terrestrial ecosystems, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Accidents climatiques. Feux de végétation, Weather damages. Fires, Feux de végétation, Forest and land fires, Biomécanique, Biomechanics, Biomecánica, Biométéorologie, Biometeorology, Biometeorología, Biophysique, Biophysics, Biofísica, Ecologie, Ecology, Ecología, Environnement, Environment, Medio ambiente, Foresterie, Forestry, Ciencias forestales, Physique appliquée, Applied physics, Física aplicada, Combustible, Fuel, Etude expérimentale, Experimental study, Estudio experimental, Incendie forêt, Forest fire, Incendio forestal, Matériau organique, Organic material, Material orgánico, Origine végétale, Plant origin, Origen vegetal, Vibration, Vibración, Action vibration, Brindille, Cedrus, Ecoulement air, Ecoulement laminaire, Feuille végétal, Module Young, Picea, Pinus, Propriété élastique, Rigidité, Transfert chaleur, Transfert masse, and Vitesse vent

Vibrations of elements of combustible forest materials (CFMs) in a laminar air flow are studied experimentally using optical-fiber facilities. The elastic properties of combustible forest materials - the Young modulus and the rigidity, whose values in the limiting cases are in satisfactory agreement with the known data - are determined. It is stated that vibrations of combustible forest materials can affect their heat and mass exchange with the environment. The results obtained made it possible to evaluate the limiting value of the equilibrium velocity of wind in the forest cover at which a crown forest fire can originate or die down.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Pollution atmosphérique due à l'industrie des combustibles et à leur utilisation, Air pollution caused by fuel industries, Mesures. Contrôle, Metering. Control, Azote oxyde, Nitrogen oxide, Nitrógeno óxido, Carbone dioxyde, Carbon dioxide, Carbono dióxido, Epuration effluent gazeux, Flue gas purification, Depuración efluente gaseoso, Gaz combustion, Combustion gas, Gas combustión, Lutte antipollution air, Air pollution control, Protección polución aire, Mesure concentration, Concentration measurement, Medición concentración, Pollution air, Air pollution, Contaminación aire, Sorbant, Sorbent, and Sorbente

Results of an energy-environmental analysis of the expediency of purifying artificial fuel gases are given. Experimental investigations have been carried out in industrial furnaces of modern structure where various kinds of high- and low-calorific gaseous fuels are used.

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Metallurgy, welding, Métallurgie, soudage, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Synécologie, Synecology, Ecosystèmes terrestres, Terrestrial ecosystems, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Accidents climatiques. Feux de végétation, Weather damages. Fires, Feux de végétation, Forest and land fires, Biophysique, Biophysics, Biofísica, Ecologie, Ecology, Ecología, Environnement, Environment, Medio ambiente, Foresterie, Forestry, Ciencias forestales, Gymnospermae, Physique appliquée, Applied physics, Física aplicada, Spermatophyta, Thermodynamique, Thermodynamics, Termodinámica, Caractéristique transfert, Transfer characteristic, Característica transferencia, Combustible, Fuel, Coniferales, Etude expérimentale, Experimental study, Estudio experimental, Incendie forêt, Forest fire, Incendio forestal, Matériau organique, Organic material, Material orgánico, Origine végétale, Plant origin, Origen vegetal, Transfert masse, Mass transfer, Transferencia masa, Adsorption, Anatomie, Cedrus, Dessiccation, Désorption, Feuille végétal, Matériau forestier combustible, Modification structure, Osmose, Picea, Pinus, Relation structure propriété, Tourbe, and Transfert humidité

The main characteristics of moisture transfer (the coefficients of moisture capacity and moisture conductivity) for the most widespread elements of combustible forest materials (CFMs), namely, needles of pine, cedar, and spruce, are found experimentally according to the procedure of A. V. Luikov, which is based on the introduction of a scale of moisture-transfer potential. The data obtained are compared with the results of other authors. Analysis of the structure of the CFM elements made it possible to establish that complex processes (desorption, adsorption, and osmosis) associated with a change in the fine structure of the needles during their drying occur inside the CFM elements.