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This article contains results of an experimental study of the process of droplets gravitating in a layer of a typical forest fuel during its thermal decomposition. Also similar experiments were carried out in conditions of moderate temperature conditions (about 300 K). Pine needles were considered as a material for study. The initial droplets’ volume was varied from 90 to 900 μL. After analysis of experimental results we established the depths, on which water droplets can penetrate into the layer of forest combustible material (FCM). The characteristic velocities of water droplets’ motion at different distances from the FCM surface were calculated. Also we determined the fraction of the mass of water consumed in the FCM layer for vaporization and cooling of the material to temperatures below the values corresponding to thermal decomposition.

To use widespreadly the waste of coals and oils processing in the great and the small-scale power generation, the key parameter, which is sectional constancy of promising organic coal-water fuels (OCWF), was studied. The compo-sitions of OCWF from brown and bituminous coals, filter cakes, used motor, turbine and dielectrical oils, water-oil emul-sion and special wetting agent (plasticizer) were investigated. Two modes of preparation were considered. They are with homogenizer and cavitator. It was established that the constancy did not exceed 5–7 days for the compositions of OCWF with brown coals, and 12–15 days for that compositions with bituminous coals and filter cakes. The injection of used oils in a composition of OCWF led to increase in viscosity of fuel compositions and their sectional constancy.

Experimental investigation of vapor formation was carried out on water droplets on fixed graphite substrate and heterogeneous droplets (containing solid single inclusions) when heating in high-temperature gas. High-speed video shooting (up to 105 frames per second), optical method (Particle Image Velocimetry) and TEMA Automotive software were used. We revealed two phase change mechanisms of heterogeneous liquid droplets. Effect of evaporation and boiling on evaporation times of water droplets was determined.

Experimental studies determining periods of suppression of thermal decomposition reaction of forest combustible materials was carried out by high-speed, cross-correlation cameras and panoramic techniques PIV and IPI under influence of water steam. Conditions and characteristics of reaction termination of thermal decomposition of forest combustible materials under reaction with steam cloud were defined.

This paper investigates the evaporation of a water droplet with a comparably sized solid nontransparent inclusion in a high-temperature (500–800 K) gas medium. Water evaporates from the free surface of the inclusion. During this process, intensive vapor formation occurs on the inner interface “water droplet – solid inclusion” with the subsequent explosive decay of the droplet. Experiments have been conducted using high-speed (up to 105 fps) video cameras “Phantom” and software “Phantom Camera Control”. The conditions of the explosive vapor formation of the heterogeneous water droplet were found. The typical phase change mechanisms of the heterogeneous water droplet under the conditions of intensive heat exchange were determined.

This paper focuses on the study of macroscopic regularities that describe how moving droplets influence on the evaporation of subsequent droplets in high-temperature gases (1100 K) and air at moderate temperatures (about 300 K). Experiments have been conducted by means of high-speed video recording and using specialized software. Investigations have been performed for two and three successive droplets with the initial radius of 1.5 mm. The effect of droplet braking, coagulation and acceleration has been defined. The typical difference between velocities, sizes and distances of successive droplets has been demonstrated.

The present study examines the characteristics of conductive heating (up to ignition temperature) of a composite fuel droplet based on coal, liquid petroleum products, and water. In this paper, we have established the difference between heat transfer from a heat source to a fuel droplet in case of conductive (hot surface) and convective (hot gas) heat supply. The Leidenfrost effect influences on heat transfer characteristics significantly due to the gas gap between a composite fuel droplet and a hot surface.

Mathematical models of heattransfer are developed for an assessment of measurement errors of temperature by thermocouples with an isolated and uninsulated seal. Dependences of necessary time of heating (for authentic measurement) for the thermocouples with an isolated seal manufactured of different materials are set. It is shown that for thermocouples with isolated seal minimum necessary duration of heating up slightly exceeds this index for thermocouples with an uninsulated seal.

This paper presents a series of experimental studies to determine the basic characteristics and features of the transformation of small water droplets (3–6 mm) and large water bombs (50–100 mm) in free fall. Investigations have been carried out using cameras “Phantom V411” and “Phantom Miro M310”. Software “Tema Automotive” have been used for data processing from video recordings. The regulations of the surface transformations of small droplets and large water bombs have been established. The stages of transformation (disintegration) have been established for large water bombs. The mechanisms of deformation have been defined for small droplets. The characteristic times have been determined for the defined stages of transformation. The study demonstrates the influence of the initial size of droplets and water bombs on the times and velocities of considered processes.

A complex model of heat supply system of building was developed by using Matlab. The model allows conducting for a wide range of research related to improving the energy efficiency of buildings. In this work the investigations of energy efficiency of several advanced insulation materials, which is characterized by different thermal characteristics, were carried out. Conclusions about the impact of the thermal protective envelope on the room thermal regime were made. Prognostic heat consumptions values of rooms with different characteristics of thermal insulation materials and main base-load envelopes were determined. Researches were conducted for the winter climatic conditions of Western Siberia: the average daily outdoor temperature is -22 °C, the amplitude of temperature oscillation is 8 °C.

Numerical investigation of flammable interaction processes of local energy sources with liquid condensed substances has been carried out. Basic integrated characteristic values of process have been defined – ignition delay time at different energy sources parameters. Recommendations have been formulated to ensure fire safety of technological processes, characterized by possible local heat sources formation (cutting, welding, friction, metal grinding etc.) in the vicinity of storage areas, transportation, transfer and processing of flammable liquids (gasoline, kerosene, diesel fuel).

Heattransfer models in a sensitive element of the resistive temperature detector taking into account temperature dependence of heatphysical characteristics of elements of the sensor are developed. The assessment of the relative deviation of results of numerical research of integral characteristics of process of heattransfer in a sensitive element of the sensor from the data obtained by means of the model which isn't considering influence of temperature on heatphysical properties of substances is executed. It is shown that the relative error of computation makes from 7,3% to 14,9% depending on type of the sensor and the taken temperature.

The experimental investigations of gas-vapor-droplet two-phase flow formation during single water droplets and their aggregate motion through high-temperature (more than 1000 K) combustion products have been conducted with usage of cross-correlation measuring facility and optical methods of “tracer” visualization (“Particle Image Velocimetry” and “Interferometric Particle Imaging”). Modes of droplet motion in high-temperature gases area have been established. It has been determined the influence of the main droplet (sizes, composition, temperature, dispersability, form, velocity) and gas (temperature and velocity) characteristics on parameters of forming gas-vapor-droplet mixtures. The main elements of advanced firefighting technologies with the usage of time and space apportioned polydisperse composition water droplet flows have been formulated. Physical and predictive mathematical models have been developed to determine the basic parameters of equipment which is necessary for operation with these technology usage.

Numerical simulation of water massif motion through the high temperature gases corresponding to the typical conditions of forest fires was carried out. Maximal values of part by volume of liquid evaporating from water massif under its motion through the flaming burning area were determined when solving the heat and mass transfer problem under the conditions of endothermic phase transformations. Influence of liquid phase transition heat on the heat and mass transfer conditions on the track of water massif was determined. The expediency of polydisperse interspaced in time and space atomization of water massifs under the large-scale (especially, forest fires) fire extinguishing was proved.

The experimental investigation of water droplet deformation (characteristic dimensions 3 ÷ 6 mm) when moving through the gas area (air) with 1÷ 5 m/s velocities was carried out. The high-speed (delay time between the frames is less than 100 ns) tools of cross-correlation videorecording were used. A cyclic change nature of the droplet shapes (from close to spherical to conditionally ellipsoidal) was found. The characteristic times of “deformation cycles” and the maximal deviations of droplet dimensions relative to initial dimensions were determined. The influence of droplet velocities and its dimensions on the deformation characteristics was determined.

A model of the building heating system, consisting of energy source, a distributed automatic control system, elements of individual heating unit and heating system is designed. Application Simulink of mathematical package Matlab is selected as a platform for the model. There are the specialized application Simscape libraries in aggregate with a wide range of Matlab mathematical tools allow to apply the “acausal” modeling concept. The conducted research of single-pipe heating system configuration and automatic control system allowed comparing the integral parameters of the systems with local and individual regulation. The results of research of thermal condition premises, situated in the extreme movement direction of the coolant are given. The conclusions about the possibility of increasing the operational efficiency of single-pipe heating system configuration in the implementation of distributed control systems are presented.

The mathematical and physical models of heat transfer were developed in order to determine the critical conditions of heat transfer in typical light-emitting diodes (LED). Operating time of LEDs under mentioned critical conditions and typical heating temperature of a compound were calculated.

A numerical research was executed for macroscopic regularities determination of heat and mass transfer processes under the conditions of phase transformation and chemical reaction at the ignition of vapour coming from fabrics impregnated by typical combustible liquid into oxidant area at the local power supply. Limit conditions of heterogeneous system “fabric – combustible liquid – oxidant” ignition at the heating of single metal particle was established. Dependences of ignition delay time on temperature and rates of local power source were obtained.

Forecasting heat and mass transfer model for the numerical investigation of liquid fuel ignition features during its spilling on the metallic substrate heated up to high temperatures was developed. The dependences of liquid fuel (by the example of kerosene) ignition delay times on the velocity of its spilling, the liquid film (which is formed) thickness and the metallic substrate temperature were found. The least values of these parameters (whereby the ignition is possible under the heat and mass transfer conditions considered) were determined.

The physical and predictive mathematical models of heat and mass transfer, phase transformations and chemical reaction have been developed to determine the necessary and sufficient conditions of inflammation and fire nascence at typical cable lines electrical overloads. The integral characteristics of study process complex – ignition delay times have been established according to cable lines electrical overloads modes. The temperature distributions in typical cable lines at overloads have been determined. The concentration variation characteristic ranges (which are sufficient for gas-phase ignition) of thermal decomposition components of cable sheaths at overloads have been adduced. The two-dimensional heat-and-mass transfer problem for a three-layer cable in the area of limited heat sink is solved. Thermal decomposition of the cable sheath and diffusion of thermal decomposition components and air were taken into account. Fire risk assessment of cable lines on overload in conditions of limited heat transfer is carried out. The dependence of ignition time delay for mixture of oxidized and thermal decomposition components from intensity of a current.

Researches of nonstationary processes of heating up of sensitive elements of thermocouples by means of one-dimensional and two-dimensional mathematical models of heat transfer are conducted. By the created models are defined duration of heating up of the sensitive elements necessary for achievement of the temperature of the thermocouple within a permissible deviation from rated direct current characteristic for three types of thermocouples – K, L and S. Distinctions in the results received by means of one-dimensional and two-dimensional models of heat transfer are shown and justified. For surface thermo-electric transformers, temperature measurement conditions are simulated in case of different value of air gap between the heater and thermocouple surface. It is shown that the value of a gap has an essential impact on minimum necessary time of measurement. Change of duration of heating up of thermocouple from heatphysical characteristics of the typical materials which are used in the case of manufacture of sensing elements is probed.

Experimental investigation of deformation regularities of widely used in industry liquid (water, kerosene, ethanol) droplets during the motion through the gas area under the action of gravitational forces has been conducted. Droplet characteristic sizes were varied in the range from 3 mm to 6 mm. Droplet motion velocities were come up to 5 m/s. Cross-correlation video recording system with optical methods of droplet size and velocity measurement was used. More than 10 characteristic droplets “strain cycles” have been established during they pass the distances up to 1 m through the gas area. The characteristic droplet forms, times, extents and amplitudes have been determined for each “strain cycle”. The expression has been formulated which describes the characteristic “strain cycles” time dependencies on droplet velocities and sizes, also on the fundamental properties (viscosity, density, surface tension) of liquid and gas area in a first approximation. The conditions of droplet deformation intensification and this process in industry gas-vapor-droplet setups stabilization have been determined.

Heat and mass transfer model for the numerical investigation of the evaporation process of a single droplet in water jet when moving through high temperature gases was developed. The integral characteristics of the process under investigation were calculated. The macroscopic regularities of water droplet evaporation, as elements of jet, in the high temperature gas mixture (as exemplified by combustion products of typical condensed substances) were determined.

Structure of microprocessed-based automation system (MBAS) of oil pumping station (OPS) «Alexandrovskaya», located on the territory of Tomsk region and forming part of the Oil Transporting Joint Stock Company «Transneft», developed in accordance with the requirements of the guidance document «Complex of the typical design choices automation of OPSs and crude storages on the basis of modern standard solutions and components».