Issue 5/2018

The article addresses the identification of thermodynamic models of buildings, serving the needs of control algorithms. It describes the issue of their modelling and approaches to identification of their parameters. It presents an approach to identification of a model with use of decomposition of the overall problem to partial, smaller, local sub-problems, which brings better scalability with the size of the model. Local models are found using grey-box identification and global consistency is achieved by coordination of shared parameters. The functionality of the method is consequently tested on data from an advanced building simulator.

The previous part of the paper evaluated the operation of the administration building Open Garden in Brno. The user comfort, feedback from the users and energy consumption of the building were evaluated for almost four years of its operation. The calculated monthly balance of the cooling need differed significantly from the measured values. Therefore, this article analyses in detail the operation of external blinds as an active element of the energy balance. An experiment was carried out assessing the use of blinds over time and the possibility of their additional incorporation in the energy model was evaluated. However, the results of the energy model with the refined inputs considering the operation of blinds still do not correspond to the measured values and the issue needs a more detailed analysis.

The paper assesses, based on numerical simulations, the variant placement of the radiator in a heated corner room with two windows. Unlike in the past times, when the installation of a radiator under each window was recommended in such a room, interesting conclusions are reached when taking into consideration the current recommended thermo-technical properties of the building structures.

The first part of the article introduces an experimental measurement of a system of heat recovery from wastewater by a heat pump. It describes the experimental equipment and design of the heat exchanger for wastewater tank. In the end, it states the results of the measurement cycles of the heat removal from the wastewater tank by the evaporator of the heat pump, while simultaneously heating water in a storage heater. The values of coefficients of performance that were evaluated from the measurement of the whole cycle were around 4.0.

Sufficient and well-designed ventilation of kitchens is a prerequisite for ensuring a high quality indoor environment in terms of temperature and humidity requirements. It is not only the removal of the produced steam and prevention of the subsequent condensed water flow, but also the elimination of all the harmful substances resulting from cooking (water vapor, aerosols or flue gases), odors and heat. Removing all pollutants from the kitchen area prevents the formation of molds and other microorganisms that could negatively affect the hygiene of the environment and the building structure of the entire space, thus affecting the operation of the kitchen. This article describes the design of kitchen ventilation according to the new set of standards ČSN EN 16282.

The article deals with the issue of heat removal from equipment operated in data centers. In recent decades, the area of information and communication technologies has been on the rise of interest. The design and solution of heat removal from these facilities will be a major challenge in the coming years for a number of specialists related to the field.

Domestic water pipes pose a risk especially for the microbiological quality of drinking water. The project of the Swiss Commission for Technology and Innovation, in cooperation with other research and professional bodies, has brought some new insights into the causes of the drinking water quality deterioration in the water supply section behind the service connection, and has formulated possible preventive measures that can be taken to a void these nega tive effects.

This article is the third, final part of the case study dealing with the topic of modeling and optimization of the reliability of drinking water supply system in the village of Žabeň using facility management tools. On the basis of the knowledge gained during modeling of the water supply network in the 2nd part of the article [6] follows its optimization, which is understood as a process of modification of water supply systems. This leads to increased efficiency of the system operation, increased reliability and minimized failure rate. Optimization is defined here by proposal of a timetable for the renovation of the water main in the model territory, based on the construction and technical condition of the water main and its lifetime, in order to guarantee a sustainable development.