The dynamic development of the automotive industry and improvements in quality of life have caused a significant increase in the production of car tires. Unfortunately, when the useful life of these products comes to an end, the problem of their disposal arises. The article presents the results of tests of epoxy mortars in which granules made from waste tires were used as a substitute for sand in the amount of 0, 20, 40, 60, 80 and 100% vol. respectively. The available literature lacks information about resin composites that arise with such a large or complete replacement of sand with rubber waste. Along with the increase in the content of waste, the values of strength parameters of composites decreased; however, a material characterized by very low water absorption, that is lightweight and with a low thermal conduction coefficient was obtained. Using the ADINA program, numerical simulations were carried out regarding the temperature distribution in a part of the building structure containing modified rubber mortar. The results of the simulation confirmed the possibility of practical use of the obtained composite due to its good thermal insulation properties. This approach to testing composites modified with rubber waste is innovative.
Among the technological solutions for external walls, the Trombe wall is an interesting proposition for obtaining solar radiation energy. The aim of the presented research is to determine the influence of glazing parameters on the thermal performance of the Trombe wall containing a phase change material (PCM). In the experimental tests, three glazing (G1, G2, and G3) with different heat transfer coefficient (Ug) and total solar energy transmittance factor (g) were used. The tests were carried out under laboratory conditions in a small-scale simulation chamber. The thermal energy of absorbed solar radiation was simulated with a heating panel. All of the walls are characterized by high dynamics of operation in the first two days. From the moment of heating, the walls achieve the minimum value of the heat flux after 16–18 h. In practice, this means the highest thermal efficiency of the wall during the night of the next day. A noticeable influence of the type of glazing on the operation of the barrier was found. The obtained results suggest that the most effective barrier for “sunny days” is the B1 barrier. The B2 barrier is suitable for alternating days in the cycle: “sunny day”, “cloudy day”. However, the B3 barrier is the most advantageous in periods with a predominance of “cloudy days”. In addition to the experimental studies, a numerical model of the B1 barrier was developed and simulation was carried out using the finite element method. The simulation results were consistent with the experimental tests. The second numerical simulation confirmed the rightness of using the heating panel in experimental tests.
The increasing costs related to the use of primary energy carriers, and greater social awareness related to the need for energy saving, necessitate the use of renewable energy sources, including solar radiation. The Trombe wall (thermal storage wall—TSW) is an indirect passive solar energy system solution, aimed at obtaining, storing, and transferring thermal energy into buildings. However, there is no comprehensive information on the impact of the use of such solutions on environmental performance in the life cycle of buildings, especially those located in temperate climates. The aim of this paper is therefore to determine the environmental impact of the construction of barriers using phase change materials (PCM) from the perspective of the life cycle of a model building conforming to the current Polish energy standard (EP < 70 kWh/(m2∙yr)). The subject of the research is the structure of a TSW using phase change materials and a reference wall with a maximum overall heat transfer coefficient of 0.2 W/m2K. A comprehensive computational model of a residential building located in Rzeszów, Poland, was created, taking into account the thermal parameters of the analyzed structure of the wall and its operation under real, specific climatic conditions, as well as the environmental characteristics. High-quality input data (based on real, long-term measurements) were used to conduct a Life Cycle Assessment of the analyzed variants. As a result, the energetic and environmental efficiency of the analyzed thermal storage wall, from the perspective of the whole building’s life cycle, were assessed. According to the analyzed data, a TSW modified with paraffin enables the reduction of the energy requirements for heating by 11.3%, and the payback period of the environmental load does not exceed 1 (GWP) and 5 (IMPACT2002+) years, which were lower than the monitored period of operation.
The article presents a comparative analysis carried out using three methods, determining the heat transfer coefficient U for a ceramic product modified with a phase change material (PCM). The purpose of the article is to determine the convergence of the resulting thermal characteristics, obtained using the experimental method, numerical simulation, and standard calculation method according to the requirements of PN-EN ISO 6946. The heat transfer coefficient is one of the basic parameters characterizing the thermal insulation of a building partition. Most often, for the thermal characteristics of the partition, we obtain from the manufacturer the value of the thermal conductivity coefficient λ for individual homogeneous materials or the heat transfer coefficient U for the finished (prefabricated) partition. In the case of a designed composite element modified with a phase change material or other material, it is not possible to obtain direct information on the above parameter. In such a case, one of the methods presented in this article should be used to determine the U factor. The U factor in all analyses was determined in stationary conditions. Research has shown a significant convergence of the resulting value of the heat transfer coefficient obtained by the assumed methods. Thanks to obtaining similar values, it is possible to continue tests of thermal characteristics of partitions by means of numerical simulation, limiting the number of experimental tests (due to the longer test time required) in assumed different partition configurations, in stationary and dynamic conditions.
The article presents the possibility of using a mass collector-storage wall (CSW), integrated into the structure of a building with a light skeleton structure. The considered system is a proposal for an energy-saving solution that can be used in buildings with various utility purposes. The article presents the results of experimental tests of a collector-storage wall mounted in the space of the skeleton structure of the southern facade of a building for the period of one year, as well as the results of numerical simulation. In the summer, the influence of the use of heat-insulating roller shutters on limiting overheating of the chamber interior was investigated. The effect of using the roller shutters is a reduction in the average value of the heat flux by about 77%. In the winter, the energy efficiency of the wall was tested. The obtained effect is energy consumption during the heating season at a level comparable to a wall with a traditional structure with a coefficient of U = 0.30 W/(m2K). The results of the numerical tests showed high agreement with the direct results, which provides a basis for the use of such simulations in further research on the search for the optimal structure of a collector-storage wall.
The article presents four equivalent methods for checking mold growth on the surface of building barriers and checking water vapor condensation on their surface. Each method applies to two parallel phenomena that may occur on a building barrier. The first method is to calculate and compare temperature factors. In the second method, the characteristic humidity in the room is calculated and compared. The third method is to calculate and compare the characteristic temperatures in the room. The fourth method is based on the calculation and comparison of characteristic water vapor pressures. Three boundary conditions are presented for each method and phenomenon: when a given phenomenon can occur, when it begins or ends, and when it does not occur. The presented methods systematize the approach to the problem of mold development and surface condensation. The presented calculation results relate to the selected building barrier functioning in specific indoor and outdoor climate conditions. The calculation results confirm the compliance of the presented methods in identifying the phenomenon of mold growth or condensation on the surface of the barrier. A graphical interpretation of the results for each method with periods of occurrence or absence of a given phenomenon is also presented.