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The indoor environment that surrounds us and the elements in it affect not only our mood but also the air quality. Vegetation elements are currently more popular, especially for their aesthetic value but also because of the fact that they affect the physical parameters of the indoor environment such as temperature and humidity. Water elements are a similar example. The presented paper combines these two elements to achieve the best possible level of thermal comfort. Experimental verification of the influence of the living wall on air temperature and humidity took place during the heating season in the city of Brno in the space of the university, while three scenarios were created: the effect of the living wall in a semi-open space, an enclosed space, and a space with a water wall with regulated water temperature. The potential of the water wall is determined based on experimental verification in laboratory conditions. The results show that the synergy of the living and water wall in the indoor space may eliminate the risk of too-low humidity during the heating season.

Nanotechnology is a perspective manufacturing technology, and in the technical fields, it deals with the production, development and utilization of technologies and materials with dimensions in nanometre sizes (1–100 nm). Nanofilters used in the article for filtration purposes consist from a nanolayer which is applied to a coarse textile backing layer, and they are inserted into the frames as conventional textile filters. The most commonly used materials are PP and PE polymers, as well as carbon, glass and metal filters. With the fabrication of nanotechnology-based filter, it is very important to choose materials, polymers with specific properties, which can be used for filtration function of the product itself. The results given in the main article compare the nanofilters with the main representatives of existing filter products currently available on the market. There is a problem with high pressure loss of the nanomaterial, and when we compare them with traditional filters, it is difficult to use them in technical practice, even if there exists the possibility for us to define the material and the thickness of the layer which are adapted to the application-specific application conditions.

The article focuses on an optimized method for Helmholtz resonators (HR) design to be used in room acoustics. They are resonators in the form of acoustic wall facings and ceilings formed by perforated boards with circular apertures. In order to verify available calculation methods for sound absorption coefficient, an experiment was performed in a reverberation room. Several variants of the internal absorbent and internal arrangement of the HR cavity for the experiment were measured. The measured data were compared with two available methods of sound absorption coefficient calculation for normal incidence using a 1D transfer matrix and electro-acoustic analogy. The calculation optimization was performed with the use of the measured data with the aim to reach better conformity of calculated courses of the sound absorption coefficient and the reverberation room measurements.

The article deals with analysis of the heat balance and temperature microclimate of indoor space of a four-storey building atrium. With regard to the anticipated thermal loads in all functionally connected rooms, investor made a request to verify the thermal stability of the atrium before the implementation stage. Atrium and adjacent rooms are a geometrically complicated inner space which cannot be solved by analytical methods to ensure the required temperature conditions in occupied zone. This led to the creation of a mathematical model of the atrium with the current project solution. The result of the simulation of the existing solutions is that there is not complied desired air temperature in the occupied zone. For this reason, it was developed optimization of existing variant. Optimization was performed in steps as changing temperature of the central air conditioning system, changing number of units and performance of local refrigeration air conditioning. The conclusion of this paper is to evaluate the thermal profiles of temperature stratification in the atrium area and request the required cooling performance of the ventilation system. The article attempts to use computer modelling as a tool for the placement and performance design of ventilation equipment.

The paper presents the possibility of management the fan performance in dependence on CO2 concentration. A mathematical calculation is made from the prediction of the electric energy consumption for a variant control algorithm. The most advantageous algorithm is programmed into the actual fan control system, and its power consumption is shown in graph. Finally, the saving of the adaptive control is compared to the classical control over time. To program the control algorithm, the CO2 mass balance equation is used. The equation depends on the input values, namely the number of CO2 sources, the room volume and the supply air. Due to the infinitely variable of fan control, it is possible to adjust the power setting depending on the expected development of the logarithmic rise of CO2 concentration in the room. This prediction is programmed with the Visual Basic code and program code can be used to the Arduino control unit, which controls the EC fan power with a 0-10 V signal. Although significant savings over a short period of time can not be expected, the ventilation system where the fan runs for a significant part of the year will be substantial. Therefore, the result will be presented by graphical diagrams of different ways of controlling the fan per year of operation.

Článek se zabývá analýzou čistoty potrubí vzduchotechniky v různých fázích výstavby. Na základě odběru vzorků je provedeno hodnocení odlišně skladovaných potrubí na stavbě. Jsou porovnány rozdíly mezi "správně" skladovaným potrubím a nechráněným potrubím. V závěru článku je shrnut dopad přenosu nečistot z potrubí na provoz vzduchotechnického systému.

Příspěvek se zabývá teoretickými metodami výpočtu odparu z povrchu vodní hladiny v bazénových halách. Motivací pro porovnání různých přístupů k výpočtu je potřeba určení produkce vodní páry v objektech bazénových hal, krytých vodních ploch, wellness center apod. Tyto poznatky jsou dále využívány pro potřeby návrhu vzduchotechnických jednotek, které mají za úkol zajistit eliminaci vodních zisků v objektech. V úvodní části článek popisuje obecnou teorii mechanizmu přenosu hmoty nad klidnou vodní hladinou a představuje současné metody pro výpočet přenosu hmoty.

The main requirements of designing the internal microclimate in swimming pool halls include removing evaporating water vapor and trichloramine (NCL3) from occurrence area of swimmers. As it is apparent from the differential equation of the mass transfer over the water surface, so with increasing speed above the water level there is increasing evaporation of water vapor at the same time. This is undesirable in view of the requirement to maintaining humidity below the upper limit of recommended limits. The article aims to point out the problem with the releasing trichloramines from the water surface and thus point to a potential increase in water vapor evaporated from the water.

Currently it is under pressure to reduce the energy consumption of the buildings. The pressure is noticeably reflected in the current way of building designing, in general. Therefore, essential part of these objects become air-conditioning (ventilation) systems, mainly due to possibilities of heat recovery and controlled ventilation. This contribution focuses on ventilation systems, low energy houses, which aims to highlight the issue of purity of these systems on the microbial level. Evaluate the impact of external and internal environment following the condition of HVAC systems in time, in the real objects. The purpose (aim) of this all is to remind that there are other aspects that have to be considered in the design and subsequently, in the use of the systems, such as the impact of the nature of the building use on the purity of air-conditioning systems. It is necessary to point out that the presented ventilation systems have a significant impact on the creation of the internal environment, and equally they can harm, instead to be beneficial.

The article deals with the description and solution of physical phenomena taking place during evaporation of water. The topicality of the theme is given a number of built indoor swimming pool and wellness centers at present. In addressing HVAC systems serving these areas, it is necessary to know the various design parameters in the interior including the water temperature as the pool temperature and humidity. Following is a description of the calculation module, air handling units, including optimizing the settings of the physical changes in order to ensure the lowest energy consumption for air treatment and required maintaining internal microclimate parameters.