Radiative cooling is an innovative and highly promising passive cooling technology that allows surfaces to dissipate heat via infrared radiation directly into the cold outer space. Unlike traditional cooling methods that require an external energy source, radiative cooling operates autonomously, offering a sustainable and energy-efficient alternative for temperature control. This natural process has attracted considerable attention in recent years due to its potential to mitigate the growing energy demands associated with air conditioning and refrigeration, which contribute significantly to global energy consumption and environmental degradation.

Keywords: radiation cooling, temperature, atmospheric window, air conditioning, energy efficiency, passive cooling, calcium carbonate, barium sulfide, boron nitride, titanium dioxide

When designing engineering structures, the efficiency of the engineer’s work is important. The cooperation between individual programs in BIM technology is very important in this aspect, because it significantly speeds up the work and, as a result, the design process is less time-consuming. In the process of designing steel structures, the first stage is the selection of an appropriate structural solution, then numerical calculations of the model together with all assigned load cases and dimensioning of individual elements of the structure in terms of the ultimate and serviceability limit state. After selecting the appropriate sections, you can start working on the detailed drawings of a given structure. When performing numerical calculations and drawings, at least two programs should be used. The article presents the cooperation between the Dlubal RFEM numerical calculation program and the Tekla Structures building structure modeling program on the example of a steel structure floor design.

Keywords: BIM, Dlubal RFEM, Tekla Structures, steel structures, direct import, engineering structures

The development of a methodology for the formation of an estimate of a construction object on the basis of its information model is considered, taking into account the state of development of software systems for BIM modeling and the peculiarities of regulatory regulation of the construction of construction projects in Russia. The factors that limit the possibility of drawing up estimate documentation for the information model have been identified. Taking into account the identified limitations, a set of operations necessary for the formation of an estimate for a construction object based on its information model is presented.

Keywords: BIM, 5D BIM-model, estimate documentation, civil and industrial construction

An approximate method for calculating the temperature field in solids heated by convection and radiation at the same time, when the thermophysical properties of the substance depend on temperature, is described. The method is based on the complex use of linearization functions and methods of numerical analysis. In the paper an example of calculation of radiation-convective heating of an unlimited plate, during which the heat capacity and thermal conductivity of the material change with temperature, is presented. The results obtained are in good agreement with the data of the finite difference method. The proposed method makes it possible to solve nonlinear problems of thermal conductivity with other boundary conditions, since the technique of solving such problems is not fundamentally different from one another. The article was published in the framework of the program of the International Forum "Victorious may 1945".

Keywords: temperature field,radiation-convective heating, thermal conductivity and heat capacity coefficients, linearizing transformation

The scheme of calculation of nonstationary temperatures in the bodies heated by the radiation which based on the established dependencies between them is presented in the article. To study the process of radiation heating of bodies, the method of linearization functions proposed by one of the authors is used. The idea of the method is as follows. The linearizing transformation leads nonlinear boundary conditions to linear boundary conditions of the third kind. The solution of the linear problem in the stage of regular temperature regime is found by multiplying the corresponding solutions of one-dimensional transfer problems. After the transformations, equations are obtained that allow calculating the temperature fields in multidimensional bodies, if the temperature distribution along the coordinate axes or on the surface is known. There is no need to know the physical parameters of the material and the degree of blackness of the body surface.

Keywords: temperature field, radiation heating, multidimensional bodies, linearizing transformation, linear boundary conditions of the third kind

The article discusses the technological capabilities of application of vibratory mechanical hard lubricant coatings on the basis of MоS2 to improve the surface quality and operational properties of parts made of aluminum with an oxide coating.

Keywords: vibration treatment, the vibration mechano-chemical coating of solid lubricant, combined methods of treatment

Numerical solution to the problem of heat transfer in boundary layers transparent Strip on the walls, exposed on the opposite side of the radiant-convective heating. Study of influence of mode parameters on heat transfer process of tasks carried out in the case of the gradient flow and included the most typical variants of transportation processes. The purpose of the real work is studying of processes of transfer at non-linear boundary conditions, obtaining approximate and analytical decisions non-linear warm and a mass transfer, establishment of communication between regime parameters and physical interpretation of results of a research. Also some conjugate problems of heat exchange in the presence of radiation are studied. The analysis received decisions is carried out. The executed research allowed to establish that existence of a transversal overflow of heat in a wall and also the radiation of a surface have significant effect on the nature of distribution of the surface temperatures.

Keywords: boundary layer, convection, radiation, gradient flow, conjugate heat transfer

Numerical solution of the problem of heat transfer in the boundary layers of transparent gas wall, exposed on the opposite side of radiant-convective heating. The energy dissipation due to viscosity is negligible, the wall is thermally thin, and the physical properties of the medium do not depend on temperature. The aim of this work - finding the local heat transfer coefficients (Nusselt number) needed for the analysis of heat exchangers. When solving the problem of nonlinear transfer functions linearizing method is used, based on which numerical scheme for computer calculations was constructed. The intensity of the local heat transfer in the boundary layer is determined by the number Kx = Nux / Nux0, where the value Nusselt numbers refer to the conditions under consideration of the problem of heat exchange (Nux) and constant surface temperature (Nux0). From a physical point of view, non-dimensional parameter Kx is a measure of the intensity of heat transfer in the boundary layer on a nonisothermal surface compared to heat transfer when the wall temperature everywhere the same. The analysis of this research showed that in radiative-convective heating number Kx on the front edge of the plate takes the largest value of Kx ≈ 1,37 corresponding to a constant heat flux on the wall. It is also shown that the relative temperature of the incoming flow has a significant impact on the value of Kx. The effect of this setting is especially evident in the processes when dominated by the effect of radiation and related to the nonlinearity of the transfer processes. The analysis revealed the influence of basic parameters of heat transfer on the development of transport processes in the boundary layer by heating radiation and convection simultaneously.

Keywords: Boundary layer, convection, radiation, radiation-convection heating, high temperature gas invironment, linearizing function

 An analysis of new methods and means for a mesurement of parameters of piezoelectric ceramic elements and materials is carried out. These methods and means are based on a digital principle of the construction of devices. An impuls with a linear frequncy modulation therein is used as an signal for exciting. Results of experimental studies on this subject are represented for discussion.     

Keywords: piezo ceramic element, piezo, methods and means of measurement, digital signal processing