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The paper describes a monitoring method of the climate of a naturally ventilated crawl space in Central Europe. The aim of the study is to analyse the temperature and humidity in the crawl space during the one-year period. The study monitors two wooden detached houses that have crawl space. The monitoring started in March and April 2022. The air temperature, relative humidity and the surface temperature of the boards and the ground is continuously monitored in the crawl spaces. In addition, the air flow is measured in one of the houses. In Central Europe, a common type of foundation for wooden detached houses is strip foundation with a concrete slab-on-ground. The aim of this study is to spread knowledge on the topic of crawl space design, which is used minimally in Central Europe although the system has its major advantages. [ABSTRACT FROM AUTHOR]

Thermal energy storage with phase change materials (PCMs) has attracted a lot of attention in the last several decades. Most PCMs do not change phase at a constant temperature but rather in a certain temperature range. It means that the PCM need to transit through its phase change temperature range to fully change phase from the solid state to the liquid state and vice-versa. The situation, in which the phase transition begins and/or ends within the phase change temperature range (in the mushy zone), is usually called a partial phase transition (or a partial phase change). The partial phase transitions occur quite often in real-life thermal energy storage systems with PCMs; especially when a PCM has a wide phase change temperature range. The behavior of PCMs during the partial phase transitions is poorly understood at the moment, because the experimental techniques used for the characterization of PCMs (such as the differential scanning calorimetry – DSC) are difficult to apply for the study of partial phase transitions. The lack of knowledge in this area influences the accuracy of phase change simulation models. The main goal of the experimental investigations, described in the paper, was to obtain data for the development of a simulation model for partial phase changes. The experimental set up for the investigation of partial phase changes of PCMs has been proposed, assembled, and the pilot measurements have been conducted. The experimental set up consists of two water storage tanks (that can be maintained at different water temperatures), a water-PCM concentric tube type heat exchanger and a data acquisition system. The water flows through the central tube of the heat exchanger while the PCM is located in the annular space of the exchanger. The water storage tanks, maintained at the temperatures within the phase change temperature range of a PCM, allow for the investigations of the heat storage cycles consisting of partial phase changes. [ABSTRACT FROM AUTHOR]

In summer, building interiors are often overheated. It is common situation especially for buildings with structures from lightweight materials (e.g. attic rooms). One of the ways to solve the excess heat removal from the interior during the summer months is integration of some phase change material (PCM) into building structures. PCMs are capable of storage latent heat at normal indoor air temperatures. In this paper, a comparison of thermal stability in two geometrically identical attic rooms is made. The difference between these two attic rooms is the composition of their building structures, as one of them contains PCM and the other does not. The thermal stability assessment is based on measuring indoor air temperatures in both attic rooms under the same climatic conditions. The measurement of individual temperatures was continuous for several days. In the conclusion, the course of temperatures in both interiors and in the exterior is evaluated and a graphic comparison of measured results is performed. [ABSTRACT FROM AUTHOR]