International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

This article provides a systemic analysis of the application of analytical methods for solving differential equations of heat and mass transfer for the design of building envelopes in the context of modern energy efficiency requirements and the digitalization of the construction industry. It is demonstrated that analytical solutions remain critical for the design of multilayer walls and roofs, thermal stability and vapor permeability calculations, and the verification of BIM models and smart home systems. A review of classic and new analytical results from 2015–2025 is presented, including the use of physically-informed neural networks (PINN) for real-time thermal protection optimization. Examples of implementation in regulatory documents, software, and microclimate management systems are provided.

To design energy-efficient buildings, it is essential to accurately calculate, monitor, and analyze their energy consumption at all stages: from conceptual (sketch) development and design to construction and operation. However, current regulatory documentation lacks methodologies that fully account for the interrelated processes occurring in building envelopes—such as heat transfer, moisture accumulation, and air infiltration—evaluate the effectiveness of specific energy-saving measures, or perform energy consumption data analysis to determine a building’s actual energy performance indicators.This highlights the relevance of calculating and analyzing building energy consumption while accounting for heat and mass transfer processes in envelope structures and the presence of various architectural and construction elements. A methodology has been developed for processing data obtained from building thermal energy metering systems. This methodology allows, during the operational phase, to determine buildings’ energy characteristics, evaluate the efficiency of thermal energy use, and assess the effectiveness of energy-saving measures.

Using the methods of systemic, mathematical and numerical analysis, as well as general physicochemical and thermodynamic laws, a complex of theoretical and experimental studies of transfer processes during short-term contact of phases has been carried out. These studies made it possible to fully reveal the regularities of external and internal heat and mass transfer, to find scientifically grounded ways to intensify the processes of vacuum, conductive and combined drying methods. Within the framework of linear nonequilibrium thermodynamics, a mathematical model of filtration-diffusion energy and mass transfer has been developed with a correct estimate of the orders of the terms in the system of differential equations of energy and mass transfer, taking into account the composition of the vapor-air mixture in the capillary-porous body. The limits of applicability of the hypothesis of short-term contact of phases according to the Fourier criterion for the transfer inside and outside the surfaces of the canonical shape (plate, cylinder, sphere) and wedge are estimated from the standpoint of the accuracy of calculating interphase flows. It is shown that in a number of cases the contact is not short-lived due to the curvature and the presence of angles on the contact surface, and not due to the finiteness of the dimensions of the contacting phases.