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The essence of the current examination is to carry out thermofluid parametric sensitivity with time-varying thermal migration of chemically reactive tiny species across an oscillating infinite plate surface. The impact of thermal motile tiny particles under the influence of many other oscillating flow parameters has yet to be investigated; hence the results obtained in this research are novel. Using a suitable non-dimensional variable, the leading PDEs (partial differential equations) are transmuted into dimensionless PDEs, ensuring equations are numerically solved using the MAPLE built-in approach. The numerical values produced in a limited scenario are linked with the outcomes found in the literature to validate the precision of the numerical approach utilized. The fluctuations in the profiles of the velocity, temperature, and concentration, in addition to the wall friction and rate of thermal and solutal transport, are illustrated via graphs and tables due to the modification of the critical parameters. The endmost results of the study concede that increasing permeability quantity and thermal and solutal buoyancy impellers intensify the fluid velocity. In contrast, a converse tendency is perceived with magnetic parameter and also, wall friction acts opposite to the velocity. The fluid temperature attenuated with dilation of the Prandtl number and radiation parameter, whilst a contrary trend was perceived with Eckert number. The increasing thermo-diffusion helps to develop fluid concentration whilst the Schmidt number and chemical reaction displayed opposite trend. Further, we achieved a tremendous conformity between the current findings and genuine results in the literature. [ABSTRACT FROM AUTHOR]

This work uses a mathematical model to investigate the impact of physical factors on the non-isothermal flow of Powell-Eyring fluid with variations in thermal conductivity and viscosity through a porous medium. The governing equations defining the flow, mass, and energy transfer issue are converted into nonlinear ordinary differential equations via selected transformation variables, and the resultant problem is numerically solved using the Galerkin weighted residual technique. This approach is implemented with Maple 18 program. The examination of the findings revealed that the radiation parameter, variations of thermal conductivity, and viscosity characteristics had a substantial impact on the flow system. This presentation includes a visual picture and explanation of how different physical characteristics affect the flow system. [ABSTRACT FROM AUTHOR]

This study focused on the impact of substrates shape on the heat radiationcharacteristics of a coating made of titanium carbide, TiC, deposited over a graphite basis. The TiC coating emissivity increase by 29.65% at 1050 °C and by 37.45% at 1650 °C when graphite, substrate surface roughness, was decreased from 3.01 µm to 0.73 µm. Simultaneously, the TiC coating's spectrum emissivity on the graphite substrate indicated the material's clear characteristic heat radiation. These findings demonstrated that the coating and substrate interacted to determine the coating's heat radiation properties. A simplified coating model created to consider how the shape of the substrate affects the coating's ability to conduct heat. Ultimately, the rough form of the substrate led to a decrease in the coating's heat radiation characteristics and an enhancement in energy loss at the interface. [ABSTRACT FROM AUTHOR]

The graphene-contained materials are added during the synthesis process of polyester resin, thus a graphene modified polyester resin is prepared. It is revealed that the introduction of graphene has no effect on the synthesis process and parameters of polyester resin, in addition, has no effect on the properties of powder coatings, such as levelling property, bending property and reactivity. However, the mechanical and durability properties of powder coatings are decreased slightly. The self-made heat-radiating device is used to investigate the graphene modified powder coatings. The results show that the addition of graphene can significantly increase the heat radiation of powder coatings. Moreover, the heat radiation property increases with the increase of the film thickness in a certain range. [ABSTRACT FROM AUTHOR]

Contemporary research has been conducted to predict the attributes of electro-magnetized blood flow doped with nanomaterials in the artery pathway through different geometries and physiological aspects. The electro-osmotically guided blood flow loaded with gold and graphene oxide (GO) nanoparticles for non-Newtonian cases via an oblique skewed arterial configuration is taken into account in the research work. The streaming model is designed by encountering the assembled impact of heat radiation, an energy source with Joule heating, wall flexibility and slip conditions, and plunged nanoparticles' shape factors. The Rabinowitsch model is employed to capture the non-Newtonian rheological traits of electrified hybrid nano-blood. The distribution of electric potential within the electric double layer (EDL) is predicted by solving the Poisson-Boltzmann equation. The complexity of the model equations is mitigated using the Debye-Hückel and lubrication approaches. A novel semi-analytical approach is prosecuted for acquiring the solutions for the finalized dimensionless model equations. Graphs and tables are used to explain the hemodynamical consequences of notable model parameters on the model entities. The worthy findings are that electro-osmotic forces have been seen to have a significant impact on the hybridized nanoparticle-infused blood mobility, which may assist medical students in maintaining adequate blood pressure during cardiac surgeries. An uprising in the Joule heating parameter is associated with a significant boost in the blood temperature profile. The model findings are expected to support biomedical research and improve pathophysiological and surgical processes. [ABSTRACT FROM AUTHOR]

Relevance. The need to analyze the current state of the subject of coal drying in order to identify the most effective methods in terms of time and energy costs, as well as environmental safety and improve the quality of fuel. As practice shows, drying is one of the most important stages in coal preparation for combustion, it helps to increase thermal efficiency, reduce emissions and environmental pollution, increase energy capacity and improve combustion stability. Among the main methods of drying coal, drying with evaporation: A) rotary drying; B) drying in a fluidized bed; C) immersion drying with hot oil; D) drying in a microwave oven, as well as drying without evaporation: A) hydrothermal dehydration; B) mechanical/thermal dehydration; C) solvent extraction, can be distinguished. At the same time, each of these methods is constantly evolving and it is required to evaluate the influence of the dynamics of these changes on the key characteristics of drying. Aim. Review and analysis of modern methods of coal drying, the most efficient in terms of time and energy costs. Object. Wet material – coal, subjected to various drying methods. Methods. Search for works on the stated topic, checking the indication of the main drying parameters: time, energy consumption, etc. Based on the data obtained, a comparison of various drying methods was carried out, and optimal methods were recommended. Results. The authors have considered the modern methods of drying coal and assessed their effectiveness. Rotary drying, hot oil immersion drying, mechanical/thermal dehydration and solvent extraction were found to be the most energy efficient methods for drying coal. The paper considers the features of each drying method.

The current study examines the effect of heat generation on thermal Marangoni convective boundary layer flow of dusty trihybrid nanofluid across a flat surface with thermal radiation and non-linear mixed convection. We consider, two phase dusty liquid model with non-linear heat generation. The fluctuation of surface tension gradients leads to the discovery of Marangoni convection. It can be used for growing crystals, drying silicon wafers, stabilising soap films, and wielding. The main objective of this study is to ascertain the trihybrid nanofluid thermal mobility. A trihybrid nanofluid consisting of magnesium oxide (Mgo), titanium oxide (TiO2), silver (Ag) and water as the base fluid is used. This model can improve the efficiency and dependability of thermal systems in a variety of applications by helping to optimize heat transfer processes in materials processing, electronics cooling, and the creation of cutting-edge cooling technologies in energy systems. The existing PDEs are converted into nonlinear ODEs via similarity variables. The nonlinear ODEs are then solved numerically using shooting technique (RKF-45th approach). When the Marangoni convection parameter rises, higher surface tension gradients lead to stronger induced flows and more efficient heat transfer inside the liquid. As the temperature profiles of the dust and fluid phases drop, the distribution of these characteristics in the liquid becomes more homogeneous.

The theory of thermal radiation and viscous heating are crucial in space engineering and high temperature activities. This inquiry analyzes the consequence of energy source/sink on steady Magnetohydrodynamic(MHD) flow of stretchable surface via porous channel taken into account the introduction of thermal radiation and viscous heating. The transformed nondimensionalized nonlinear governing model is numerically classified and resolved to derive solutions for the physical terms using shooting techniques along with 4th order Runge Kutta method. The flow behavior represented through the physical parameters are discussed via tables and graphs. Examined are the effects of skin friction as well as Sherwood and Nusselt numbers. It is revealed from the research that increase in micropolar term leads to higher velocity and temperature while microrotation falls. Also, increase in temperature is observed for every increase in porosity, Eckert, radiative and heat source terms. It is deduced from the investigation that the temperature can be enhanced as both radiative and viscous heating terms improves.

This work uses a mathematical model to investigate the impact of physical factors on the non-isothermal flow of Powell-Eyring fluid with variations in thermal conductivity and viscosity through a porous medium. The governing equations defining the flow, mass, and energy transfer issue are converted into nonlinear ordinary differential equations via selected transformation variables, and the resultant problem is numerically solved using the Galerkin weighted residual technique. This approach is implemented with Maple 18 program. The examination of the findings revealed that the radiation parameter, variations of thermal conductivity, and viscosity characteristics had a substantial impact on the flow system. This presentation includes a visual picture and explanation of how different physical characteristics affect the flow system.

The research considers the microwave treatment of snow-and-ice mass comprising the stages of heating and melting. A nonlinear mathematical model for two-phase Stephan problem was developed for the case of sandwich dielectrics system. We offer approximate analytical solutions that take into account the thermophysical and electrophysical properties of dielectric layers; this approach allows parametric analysis. [ABSTRACT FROM AUTHOR]

A multiplicity of simulations is required to optimize systems with thermal transient processes in the presence of uncertain parameters. That is why model order reduction is applied to minimize the numerical effort. The consideration of heat radiation and convection with parameter-dependent heat transfer coefficients results in a nonlinear system with many inputs as these loads are distributed over the whole surface limiting the attainable reduced dimension. Therefore, a new input reduction method is presented approximating the input matrix based on load vector snapshots using singular value decomposition. Afterward, standard reduction methods like the Krylov subspace method or balanced truncation can be applied. Compared to proper orthogonal decomposition, the number of training simulations decreases significantly and the reduced-order model provides a high accuracy within a broad parameter range. In a second step, the discrete empirical interpolation method is used to limit the evaluation of the nonlinearity to a few degrees of freedom and proper orthogonal decomposition allows the fast adaptation of the emissivity. As a result, the reduced system becomes independent of the original dimensions and the computation time is reduced drastically. This approach enables an optimal method combination depending on the number of simulations performed with the reduced model. [ABSTRACT FROM AUTHOR]

The relationship among the length of arcs, slag layer height, efficiency of arcs, and specific power consumption of high-power arc steel-making furnaces has been established in this study. When working on 400–430-mm-long arcs, with the depth of the arc penetration into the bath and slag of 425–500 mm, the average value of the arc efficiency for melting is 0.78–0.80, and the specific power consumption for the EAF-100 furnace is 360 kW·h. The predicted, calculated, and real specific power consumptions, depending on the length of arcs, slag layer height, depth of arcs in the slag, and efficiency of arcs, coincide or differ by 2%–5%. [ABSTRACT FROM AUTHOR]

Blood‐contaminated shoeprints and footmarks contain valuable operational information as they may bind an individual who stepped in the crime scene with the incident and not merely with the location. As determining the age of a bloodstain remains a challenge, while processing the scene, it is difficult to determine whether the blood is completely, or partially, dry. Thus, executing a dye staining protocol may wash these marks away as they might still be soluble. However, to meet this challenge, it is possible to fix blood marks using heat. This study aims to find a solution for floor surfaces covered by heavier blood traces (shoeprints and footmarks). For this purpose, a new pseudo‐operating device was constructed for examining the blood‐fixing process of both mentioned trace types. Two trials were performed with depletion marks. The results revealed that fully developed fresh and heavily blood deposits were obtained by heating to 200°C for 7.5 min using the fixing device, followed by a staining protocol using amido black solution. The achieved sharp resolution of the examined bloody prints demonstrates that in certain cases the dehydration mechanism of heating is preferred over precipitating the proteins attributed to 5‐sulfosalycilic acid; thus, reducing the risk of washing blood evidence while processing the crime scene. [ABSTRACT FROM AUTHOR]

This paper considers the microwave processing for snow-ice mass comprising the heating and melting stages. The search for basic patterns of these processes aimed at optimization, control, and the design of stages is based on mathematical models and their implementation using analytical or numerical methods. A nonlinear mathematical model of the two-phase Stefan problem for a layered system of dielectrics was constructed. This approach takes into account the dependences of the medium permittivity and other parameters on the medium temperature and the design of a microwave radiation source. [ABSTRACT FROM AUTHOR]

This article presents the calculation results of the heat transfer in a high-power electric arc steel-making furnace EAF-100. With an increase in the slag layer height, the radiation heat fluxes from arcs to the walls decrease, while the surface of the bath and spherical segments under the arcs increase. With the full penetration of the arcs into the bath and slag, the density of the thermal radiation fluxes of the arcs is reduced by three times over the entire height of the walls compared with an insignificant embedding of the arcs. Thermal loads on the water-cooled wall panels in the absorbing furnace atmosphere are reduced by four times compared to those in the transparent furnace atmosphere. [ABSTRACT FROM AUTHOR]

The feasibility of the future more-electric, hybrid-electric, and all-electric aircraft configurations will depend on a good understanding of thermal aspects early in the design. However, thermal analysis of aircraft equipment bays is typically performed at later design stages to validate if the design meets the minimal certification requirements rather than to optimize the cooling strategy. The presented work aims to provide new insight into thermal aspects in typical aircraft equipment bays. In particular, system thermal interactions, such as radiation, play a more significant role in tightly packaged bays, such as avionics bays. This paper investigates the influence of radiation on the overall system heat dissipation in two representative avionics bays. Using Computational Fluid Dynamics (CFD) simulation, combined with an analytical approach, the authors analyze the impact of several parameters, such as varying mass flow rates and distances between adjacent systems, on their thermal interaction. The results suggest that the radiative effects must be considered when the gap distance between the systems is larger than 0.1 m, the flow rate between two systems is not strong enough to have high convective heat exchanges, when the systems of interest are hidden by other systems from the ventilation sources, and when the system's internal heat dissipation is significant. Overall, this paper's results will contribute enhance conceptual design methods, such as the previously developed Thermal Risk Analysis, and help optimize thermal management strategies for future aircraft. [ABSTRACT FROM AUTHOR]

• A novel freeze and cold storage system with an additional electric radiant heater is proposed. • A comprehensive evaluation method of system thermal performance is applied. • Thermal parameters are compared and optimized by the experimental method. • The system thermal performance is improved at the optimum thermal conditions. Improvement of thermal efficiency for isobutane refrigeration system could match well with the building requirements of low-carbon, and sustainable development. The electric radiant heater (ERH) is widely used for the freeze and cold storage (FCS) system, but it has problems of high electric consumption and high freezer compartment temperature rise (FCTR) as a result of low heat-transfer efficiency under defrosting. Therefore, a novel FCS system with an additional electric radiant heater (AERH) based on the heat required for frost melted and synchronous defrosting is proposed. The defrosting consumption and the FCTR of the novel FCS system are comprehensively evaluated by a novel evaluation method. Besides, the effect of the thermal parameters (i.e., the defrosting pause temperature, the position, and electric power of the AERH) on the heat transfer characteristics are compared and optimized by the experimental method. Finally, a novel method is presented to predict the optimum thermal conditions. The results show that the optimum system thermal performance is obtained, the defrosting duration and defrosting consumption are reduced by 44.02 % and 37.03 %, and the defrosting efficiency and energy efficiency could be increased by 17.92 % and 9.96 %, respectively, as compared to the conventional FCS system. The proposed FCS system has better economic performance and heat transfer efficiency. Meanwhile, 30.54 kg of CO 2 emissions could be avoided during the annual operation period, and the environmental benefits are also considerable. This study not only reaffirms the benefit of using the AERH for defrosting in the FCS system but also provides a reference for the promotion and application of efficient heat transfer technology in building refrigeration engineering. [ABSTRACT FROM AUTHOR]

With the large-scaling and intensification of crude oil reserves, storage tanks are also developed in the direction of large capacity. Hence, it is easy to trigger a chain fire effect in the tank farm once a fire occurs, causing huge economic losses and even casualties. In order to reasonably design the safety distance of large crude oil storage tanks and reduce the heat radiation effect of the firing tank on the adjacent tanks, the fire of the storage tank was numerically simulated with the CFD technology. Meanwhile, the influence of the three factors, including the wind speed, spray intensity and oil burning rate, on the safety distance of large crude oil storage tanks were analyzed by controlling a single variable and designing the orthogonal working conditions. The results show that the three factors ranking in a decreasing order of influence are the spray intensity, wind speed and oil burning rate successively. To reduce the safety distance between the storage tanks, it is recommended to increase the spray intensity of cooling water. Thereby, the research results could provide guidance for the layout design of crude oil reserves.

In this paper, the safety and thermal comfort of protective clothing used by firefighters was analyzed. Three-dimensional geometry and morphology models of real multilayer assemblies used in thermal protective clothing were mapped by selected Computer-Aided Design (CAD) software. In the designed assembly models, different scales of the resolution were used for the particular layers – a homogenization for nonwoven fabrics model and designing the geometry of the individual yarns in the model of woven fabrics. Then, the finite volume method to simulate heat transfer through the assemblies caused by their exposure to the flame was applied. Finally, the simulation results with experimental measurements conducted according to the EN ISO 9151 were compared. Based on both the experimental and simulation results, parameters describing the tested clothing protective features directly affecting the firefighter's safety were determined. As a result of the experiment and simulations, comparable values of these parameters were determined, which could show that used methods are an efficient tool in studying the thermal properties of multilayer protective clothing. [ABSTRACT FROM AUTHOR]

The Cabinet-type ERK solar dryer is manufactured by a temperature distribution process so that the temperature inside the appliance is well distributed. The cabinet-type ERK solar dryer comprises several components to maintain the water content, including a drying oven, air blower, heat-resistant pipe, hot water pump, thermostat, heat exchanger, and heater. These tools are used to convert heat radiation into conduction or convection so that the dried agricultural products' water content is relatively low. The data needed to show the quality of the tool include temperature on temperature received by the wall (Tw), absorbent plate (Tp) and room temperature (Tr). And as for other supporting data including the environmental air/ambient temperature (Ta) and solar irradiation (I) for optimal tool usage time. The experiment results for 5.5 hours, as many as 23 measurements with time interval 15 minutes, obtained a relatively unchanged temperature distribution. During that time, the average temperature received by the wall (Tw) was 41.26 °C, while the middle plate temperature (Tp) was 40.65 °C and room temperature (Tr) was 40.71 °C. Thus, the temperature in the Cabinet-type ERK solar dryer is well distributed. The distribution percentage between wall temperature and plate temperature is 98.52 %, while wall temperature and room temperature are 98.67 %. The result indicates that the Cabinet-type ERK solar dryer is potential as a drying device for agricultural commodities. It is hoped that the Cabinet-type ERK solar dryer will be an alternative to a drying system that can improve the quality of agricultural commodities for farmers in Indonesia. [ABSTRACT FROM AUTHOR]

For now, the introduction of fillers with highly intrinsic thermal conductivity (TC) into polymers is the most effective way to prepare composites with excellent heat dissipation capability. However, reducing the filler loading without lowering the TC is the most challenging. In this article, patterned electrospinning and hot pressing were employed to prepare thermally conductive and electrically insulating polyvinylidene fluoride (PVDF)-based composites containing 20 wt% boron nitride nanosheets (BNNSs) as the dominant filler and 5 wt% Al 2 O 3 nanopowders as the auxiliary filler. We have proven "1 + 1>2″ in terms of enhancing the TC of composites at nanoscale by the synergistic effect of nanosheet and nanopowder. The results showed that the in-plane TC (8.55 W/(m·K)), volume resistivity (1.56 × 1015 Ω cm), and breakdown strength (406.2 kV/mm) of the composites were improved by 4759.1 %, 649.0 %, and 34.1 % compared with the neat polymer, respectively. Furthermore, the potential application of such composites in contact heat dissipation and radiative cooling was demonstrated by the experiment of integrating cordierite particles with high infrared radiation onto the films. [Display omitted] • An interface material integrating heat conduction and radiation was prepared. • The TC of the composites containing 20 wt% BN and 5 wt% Al 2 O 3 reached 8.55 W/(m·K). • "1 + 1>2″ of nanosheet/nanopowder on the enhancement of TC was confirmed. • Excellent contact and non-contact heat dissipation were achieved. [ABSTRACT FROM AUTHOR]

The paper presents an assessment of the unwanted temperature non-uniformity found in high temperature applications of the pulse calorimetry technique. Specimens in the form of a solid cylinder undergoes fast electrical heating and an intense heat radiation at high temperatures, coupled with the heat conduction the specimens' cold ends, make them having a highly non-uniform temperature distribution, both in their radial and axial directions. By using finite element method simulations of a typical pulse calorimetry experiment, the temperature non-uniformity across the specimen diameter and along the specimen effective length has been estimated for different specimen dimensions and materials, as well as for different heating rates. The obtained results suggest that an optimization of experimental parameters, such as the specimen diameter, specimen total and effective length and heating rate, is needed for minimization of the temperature non-uniformity effect. [ABSTRACT FROM AUTHOR]

The phase-field formulation for fracture based on the framework of representative crack elements is extended to transient thermo-mechanics. The finite element formulation is derived starting from the variational principle of total virtual power. The intention of this manuscript is to demonstrate the potential of the framework for multi-physical fracture models and complex processes inside the crack. The present model at hand allows to predict realistic deformation kinematics and heat fluxes at cracks. At the application of fully coupled, transient thermo-elasticity to a pre-cracked plate, the opened crack yields thermal isolation between both parts of the plate. Inhomogeneous thermal strains result in a curved crack surface, inhomogeneous recontact and finally heat flow through the crack regions in contact. The novel phase-field framework further allows to study processes inside the crack, which is demonstrated by heat radiation between opened crack surfaces. Finally, numerically calculated crack paths at a disc subjected to thermal shock load are compared to experimental results from literature and a curved crack in a three-dimensional application are presented. [ABSTRACT FROM AUTHOR]

Coal mined from the surface or underground is rarely suitable for direct use and requires preparation based on physical and/or chemical methods of removing certain components in order to improve the quality of coal to the required level. High humidity leads to a decrease in the energy efficiency of boiler, so the process of fuel drying is a necessary step in coal preparation, and reducing energy costs for moisture removal is an urgent task. One of the ways of moisture reduction is coal treatment with microwave radiation. As compared with other methods, microwave drying has the following features and important advantages: 1) volumetric heating; 2) selective heating (there is no energy absorption in dried areas); 3) low thermal inertia. However, this method requires high power inputs and there is a need to find energy-efficient processing regimes. In the present work, a drying model has been constructed, the optimal regime of layer drying has been found using the finite element method at the example of brown coal from the Talovsky deposit, and energy costs have been determined. [ABSTRACT FROM AUTHOR]

Due to the complex effects of combined loadings on complete steel structures, the combined effects of high-velocity projectile impact and heat radiation due to a pool-fire on a vertical Q345 steel tank have not been generally considered. In this study, a consecutive coupling approach is established. The combined effects of projectile perforation and heat radiation on the failure modes and fire resistance of a vertical steel tank are investigated. Additionally, the effects of the projectile size, projectile shape, and separation distance are analyzed. The results indicate that compared with a fixed-roof tank without impact, the perforation results in stress concentrations in the plastic deformation zone. The stress level of the perforated tank is higher, and the fire resistance of the perforated tank is lower. Additionally, as the perforation size increases, the stress level triggering the thermal buckling of the perforated tank decreases outside of the plastic deformation zone. Additionally, the fire resistance decreases. Moreover, as the separation distance decreases, the stress level of the cylindrical shell increases. The fire resistance of the perforated tank decreases dramatically. By understanding the failure mode, this study is able to suggest fire and explosion protection measures in petrochemical industries to decrease or eliminate the domino effect risk and incident damage. Additionally, the fire resistance data can help improve guidelines and understanding for fire and rescue services, which would undoubtedly play a vital part in emergency response and rescue, and enhance the process safety level overall. [ABSTRACT FROM AUTHOR]

In this paper, the safety and thermal comfort of protective clothing used by firefighters was analyzed. Three-dimensional geometry and morphology models of real multilayer assemblies used in thermal protective clothing were mapped by selected Computer-Aided Design (CAD) software. In the designed assembly models, different scales of the resolution were used for the particular layers – a homogenization for nonwoven fabrics model and designing the geometry of the individual yarns in the model of woven fabrics. Then, the finite volume method to simulate heat transfer through the assemblies caused by their exposure to the flame was applied. Finally, the simulation results with experimental measurements conducted according to the EN ISO 9151 were compared. Based on both the experimental and simulation results, parameters describing the tested clothing protective features directly affecting the firefighter’s safety were determined. As a result of the experiment and simulations, comparable values of these parameters were determined, which could show that used methods are an efficient tool in studying the thermal properties of multilayer protective clothing.

The main factor of oil tank fire spread should be attributed to the fire's heat radiation. Affected by the heat radiation transferred from the flame of the firing tank, adjacent tanks are easily ignited and may cause a widespread fire in the entire tank farm. In order to study the distribution rule of heat radiation on tank wall when adjacent tanks are exposed to heat radiation, the small-sized experimental device of the heat radiation influence of burning tank on adjacent tank a smallscale experimental device for the influence of tank combustion on the heat radiation of adjacent tanks was established to conduct the experimental study on heat radiation distribution of adjacent tank wall under fire conditions. The experimental results show that under fire conditions, the adjacent tank wall in front of the firing tank is most exposed to radiation. The heat radiation drops gradually from the tank roof to the tank bottom and symmetrically from the center line to both sides. As the L/D(L is the distance between two adjacent oil tanks, and D is the diameter of the oil tank) ratio increases, the heat radiation on the adjacent tank decreases. The experimental data can provide a reference for the heat radiation research of adjacent tanks under fire conditions, and is of great significance for preventing adjacent tanks from being ignited and preventing fire and explosion accidents in tank farm.

The relevance of the research is dictated by the need to develop mathematical models of microwave heating and MV-drying of wet materials to obtain technologically optimal and cost-effective modes. This publication is a continuation of the articles of the same authors in The Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, in which using mathematical modeling, the authors have studied in details the process at the first and second stages of drying – the heating stage, when heat exchange between the surface of a wet body and the environment occurs due to radiation and convection, and microwave energy is absorbed by the surface layer owing to its small penetration depth, as well as the stage of constant drying rate. The authors constructed the asymptotic solutions of this nonlinear problem for small and large values ​​of dimensionless time, which are demanded by engineering practice, both for parametric analysis and for performing operational calculations. The approach associated with the consideration of the third stage – the stage of the falling drying rate, is based on determination of the basic drying equation, which provides the relationship between heat transfer and moisture exchange using the Rebinder criterion. The aim of the researchis tostate the problem of the third stage of microwave drying of a wet material – the stage of a falling drying rate, and to implement a theoretical solution to determine temperature field distribution over the layer thickness and the drying rate. The object of the research is a flat layer of wet material – coal, sand, wood, etc. capillary-porous arrays, which are affected by microwave radiation. Such materials have a high dielectric constant and, as a result, very effectively absorb microwave radiation, which is almost 100% converted to thermal energy. The research methodsare associated with mathematical modeling, which are based on the equations of Maxwell’s electrodynamics and heat and moisture transfer by A.V. Lykov. In this article, when assessing the parameters of heat and moisture transfer, heat transfer accounting is conducted in more details than mass transfer. One of the features of this problem is the consideration of materials with a small depth of absorption, whereby the source term in the system of equations for heating is in the boundary condition. The temperature and moisture content of the body to be dried were determined in the mode of the falling drying speed, the calculated analytical ratios for small and large parameters of time were obtained.

The relevance of the research is dictated by the need to develop mathematical models of microwave heating and MW-drying of wet materials to obtain technologically optimal and cost-effective modes. This publication is a continuation of the article by the same authors in «Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering», in which the authors using mathematical modeling, studied in detail the process at the first stage of drying –the heating stage, when heat exchange between the surface of a moist body and the environment is due to radiation and convection – energy is absorbed by the surface layer due to its small depth of penetration. The authors constructed the asymptotic solutions of this nonlinear problem for small and large values ​​of dimensionless time demanded by engineering practice, both for parametric analysis, and for carrying out operational calculations. The approach associated with the consideration of the second stage, the stage of constant drying rate, is based on a more detailed study of heat transfer, and the calculation of the rate of drying is carried out using the approximation dependence of A.V. Lykov. The paper proposes a condition for cross-linking of thermal modes of I and II stages of drying. The aim of the research is the state of the problem of the second stage of microwave drying of wet material – a stage of constant drying rate – and implementation of a theoretical solution to determine the distribution of the temperature field across the layer thickness and the magnitude of the drying rate. The object of the research is a flat layer of wet material – coal, sand, wood, and other capillary-porous arrays, which are affected by microwave radiation. Such materials have a high dielectric constant and, as a result, very effectively absorb microwave radiation, which is almost 100 % converted to thermal energy. The research methods are associated with mathematical modeling, which are based on Maxwell's electrodynamics equations and A.V. Lykov heat and moisture transfer. In this article, the Maxwell problem is solved independently of the problem of heat and mass transfer; therefore, the flux density absorbed by microwave radiation is known. Also, one of the features of this problem is the consideration of materials with a small absorption depth, that is why the source term in the system of equations for heating is in the boundary condition. As a result of the research, the authors involving the stationary temperature field conditions and the constancy of the moisture content flux density over time stated and solved the problem of temperature field distribution across the thickness of the wet plate, which strictly follows the square parabolic law. The drying speed of the II stage and the critical moisture content at the end of the II stage were determined from A,V. Lykov correlation dependencies. The paper introduces the stitching solutions for the I and II stages and the analysis of the constructed solutions.

The feasibility of the future more-electric, hybrid-electric, and all-electric aircraft configurations will depend on a good understanding of thermal aspects early in the design. However, thermal analysis of aircraft equipment bays is typically performed at later design stages to validate if the design meets the minimal certification requirements rather than to optimize the cooling strategy. The presented work aims to provide new insight into thermal aspects in typical aircraft equipment bays. In particular, system thermal interactions, such as radiation, play a more significant role in tightly packaged bays, such as avionics bays. This paper investigates the influence of radiation on the overall system heat dissipation in two representative avionics bays. Using Computational Fluid Dynamics (CFD) simulation, combined with an analytical approach, the authors analyze the impact of several parameters, such as varying mass flow rates and distances between adjacent systems, on their thermal interaction. The results suggest that the radiative effects must be considered when the gap distance between the systems is larger than 0.1 m, the flow rate between two systems is not strong enough to have high convective heat exchanges, when the systems of interest are hidden by other systems from the ventilation sources, and when the system’s internal heat dissipation is significant. Overall, this paper’s results will contribute enhance conceptual design methods, such as the previously developed Thermal Risk Analysis, and help optimize thermal management strategies for future aircraft.

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The relevance of the research is determined by the need to develop mathematical models of microwave heating and MW-drying of wet materials to obtain technologically optimal and cost-effective modes. Due to the complexity and non-linearity of the processes taking place inside wet materials during microwave processing, it is extremely important to build models that would allow one to construct analytically approximate solutions in order to find the main laws and characteristic features of the processes under consideration. The aim of the research is to state the first stage of the microwave drying of wet material – the warm-up phase. The search for analytical solution for the temperature of the layer at different points in time allows us to determine the beginning of the next stage – drying. The object of the research is a flat layer of wet material – coal, sand, wood and other capillary-porous arrays, which are affected by microwave radiation. Such materials have a high dielectric constant and, as a result, they very efficiently absorb microwave radiation, which is almost 100 % converted to thermal energy. The methods are associated with mathematical modeling, which are based on Maxwell electrodynamics equations and heat and moisture transfer of A.V. Lykov. In this article, the Maxwell problem is solved independently on the problem of heat and mass transfer; therefore, the flux density of the absorbed microwave radiation is assumed to be known. Also, one of the features of this problem is the consideration of materials with a small depth of absorption, whereby the source term in the system of equations for heating is in the boundary condition. As a result of the research the problem of heat transfer at a given power source of heat was solved using asymptotic procedures. The authors have obtained approximate analytical solutions for the first of the three characteristic stages of microwave drying under conditions of low penetration depth of microwaves: the warm-up stage of a moist material. The constructed solutions were analyzed.

Classical thermodynamics often helps to passively describe macroscopic heat phenomena of natural systems, which means people almost cannot change the heat phenomena, but understand them according to the four thermodynamic laws. In contrast, thermal metamaterials, together with the governing theories, make it possible to actively manipulate macroscopic heat phenomena of artificial systems, which enables people to change the heat phenomena at will. Such metamaterials or metamaterial-based devices refer to those artificial structures that yield novel functions in controlling heat transfer. Since the concept of thermal cloak was proposed in 2008, this field has been developed rapidly with fruitful research results, which range from both theoretical models and experimental techniques in scientific research to practical applications in industry, such as radiative cooling and infrared camouflage. In this review, we comb through the research history of thermal metamaterials, and present novel functions and their associated theories in four areas. Such theories include both transformation theories and their extended theories, which are called theoretical thermotics for convenience. The four areas are classified according to the different ways of heat transfer, namely, heat conduction, heat conduction–convection,​ heat conduction–radiation, and heat conduction–convection–radiation. The corresponding experiments and applications are also introduced. At last, we provide our views on future opportunities and challenges in thermotics of metamaterials. [ABSTRACT FROM AUTHOR]

Analytical formulation of nonisothermal injection in geological reservoirs remains challenging, and researchers have adopted a number of simplifying assumptions to theoretically predict the resulting geomechanical alterations. One common assumption behind current thermo‐poroelastic solutions is a constant temperature and constant pore pressure in the reservoir rock adjacent to the source/sink, which results in an unrealistic discontinuity in the rock temperature profile, ignoring the gradual geomechanical changes at this location. Another common assumption in previous studies is the plane strain approximation, thus ignoring vertical interactions between the target layer and the surrounding rocks. This paper presents new closed‐form thermo‐poroelastic solutions for nonisothermal injection in a low permeable porous layer confined with flexible sealing rocks. The transient nature of temperatures in the rock adjacent to the source/sink is incorporated through implication of a temporal heat and fluid flux boundary condition. The impact of vertical confinement is also integrated using the Winkler model. The proposed solutions are proven to capture generation of short‐term thermal‐induced pore pressures near the wellbore, which cannot be captured using conventional solutions. It is also demonstrated that the conventional solutions obtained using constant pore pressure and temperature boundary are in fact a special case of the proposed solutions, and the latter yield the former where the heat transfer between the source/sink and the rock occurs quite rapidly. The vertical confinement is also shown to have a notable impact on the induced stresses‐strains, and thus should be incorporated when studying wellbore stability or assessing seal rock integrity during nonisothermal injection. [ABSTRACT FROM AUTHOR]

The limited stability and heat insulation performance of the traditional aqueous film forming foam (AFFF) affects its efficiency in fire extinguishing. Recently, functional nanoparticles have been used as stabilizers. The formed three-phase foam exhibits better performance. However, the mechanisms and heat transfer behaviors of the three-phase foam are still unclear and require further clarification. Therefore, in this study, the thermal stability, the volume expansion, and the temperature profiles inside the foam layer exposed to the high-temperature environment are studied. The results indicate that the high ambient temperature benefits the foaming but reduces the foam stability. The foam layer exposed to continuous radiant heating presents three successive stages, i.e. the initial stage, the balanced stage, and the collapse stage due to distinct heat transfer characteristics in the depth direction. Moreover, the effects of foam composition and operation conditions on foam insulation are further evaluated. It is found that the insulation performance of foam can be enhanced with higher particle concentration, especially hydrophobic particles. High foam expansion ratio leads to better foam stability but worse thermal insulation. The life of foam decreases with the radiation heat flux. The results provide useful guidance for achieving high fire-extinguishing efficiency of foam. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Architectural Journal / Jian Zhu Xue Bao is the property of Architectural Journal Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The horizontal rotary retort is one of the important equipment in oil shale retorting by solid heat carrier technology, in which the heating of oil shale plays a crucial role in shale oil production. In this work, a comprehensive heat transfer model including both conduction and radiation under contact and non-contact conditions was proposed to numerically investigate the heat exchange among particles at five different pathways by employing the discrete element method (DEM). The effects of particle physical parameter (particle size) and operating conditions (rotational speed and fill ratio) on thermal characteristics such as oil shale heating time, thermal rate, thermal index and heat flow were deeply analyzed. In summary, the heat flow generated by particle-fluid-particle heat conduction contributed 66–71% of the total heat flow, the radiative flow produced by particle-particle heat radiation was 22–30%, and the thermal contribution of particle-particle heat conduction was the least, accounting for only 6–7%. Unlabelled Image • Application of the comprehensive thermal DEM model in horizontal rotary retorts. • Intricate mechanisms including both heat conduction and heat radiation. • Effects of particle physical parameter and operating conditions. • Contribution of five different heat transfer pathways to the total heat flow. [ABSTRACT FROM AUTHOR]

Radiative heat transfer across nanoscale-thick layers attracts considerable attention because of its importance for modern technology, and also because of the evidence that conventional methods of radiative heat transfer fail at such small scales. This paper analyzes several approaches to this problem that have been proposed since the late 1960s when the first adaptations of the classical Stefan–Boltzmann law of radiative heat transfer to smaller scales were presented. It is shown that while all authors agree that thermal radiation is described by Maxwell's equations for electrodynamics, the methods of these studies drifted from deductive reasoning based on these equations toward heuristic guesses. This paper identifies critical points of several of these previous studies that are responsible for the lack of a suitable theory of radiative heat transfer across nanoscale layers despite almost 50 years of effort. Among these points are: (1) attempts to describe heat transfer using statistical distributions that are limited to equilibrium systems that cannot produce any heat flux; (2) application of the so-called fluctuation–dissipation theorem when its conditions are not satisfied; (3) the failure to distinguish between different kinds of evanescent fields; (4) an unjustified assumption that resonant surface waves can transfer heat by tunneling. [ABSTRACT FROM AUTHOR]

The present study investigates the effects of thermal radiation and chemical reaction on magnetohydrodynamic flow, heat, and mass transfer characteristics of nanofluids such as Cu–water and Ag–water over a non‐linear porous stretching surface in the presence of viscous dissipation and heat generation. Using similarity transformation, the governing boundary layer equations of the problem are transformed into non‐linear ordinary differential equations and solved numerically by the shooting method along with the Runge–Kutta–Fehlberg fourth–fifth‐order integration scheme. The influences of various parameters on velocity, temperature, and concentration profiles of the flow field are analysed and the results are plotted graphically. A backpropagation neural network is applied to predict the skin friction coefficient, Nusselt number, and Sherwood number and these results are presented through graphs. The present numerical results are compared with the existing results and are found to be in good agreement. The results of artificial neural network and the obtained numerical values agree well with an error <5%. [ABSTRACT FROM AUTHOR]