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Archiv článků od 3.10.2011 do 16.4.2012

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vzduchotechnické klapky
16.4.2012
Ing. Miroslav Kučera, Ph.D., doc. Ing. Richard Nový, CSc.

The topic area of this article continues in focusing to noise and control properties of round dampers in HVAC systems. The acoustic and hydraulic properties of the round damper and systems of two dampers lined in series with a differently designed control flap under the pre-defined conditions are presented herein in mutual relationships. Authors submit recommendation as to the selection of a suitable damper type with respect to the noise lowering and good control abilities.

UV záření
9.4.2012
Ing. Petr Vrbík, Zdravotní ústav se sídlem v Brně

The paper deals with the possible health risks of exposure of persons to ultraviolet radiation primarily from incoherent technological resources. It talks about the effects on the human body and hygiene limits, the criteria for assessing health risks, the method of measurement and hygienic supervision at the preview of this issue, including the use of UV radiation in commercial tanning salons.

blower door test
9.4.2012
Mgr. Stanislav Paleček, předseda Asociace Blower Door CZ

This paper deals with the development of measurement of the building envelope airtight in the Czech Republic. Specifies the initial criteria and mistakes that were made. Addresses in detail the current state of measuring air tightness and provides some interesting insights from practice. The paper was presented at a conference Passive Houses 2011.

PCM
2.4.2012
Ing. Milan Ostrý, Ph.D., Ing. Roman Brzoň, Ing. Tomáš Klubal

Thermal stability of rooms without air-conditioning depends mainly on the thermal energy storage capacity of envelope and possible heat gains. Sensible heat storage structures, e.g. brickwork, concrete walls and slabs, usually do not have sufficient thermal storage capacity and some additional thermal storage mass is needed for cold storage. Passive cooling with thermal storage in phase change materials (PCMs) is a very effective way to improve thermal stability of the rooms with light-weight envelope. The main advantage of the phase change materials storage in buildings is the possibility to store a huge amount of heat in a rather narrow temperature interval. Passive cooling based on the latent heat storage technology can contribute to the energy and operative cost savings during summer season. The efficiency of this kind of passive cooling significantly depends on the heat transfer rates between the ambient environment and the thermal storage material. Modern administrative buildings or wooden buildings are often made of light-weight materials with rather small thermal mass. The latent heat cold storage in the phase change materials seems to be quite promising in this respect since it offers high thermal storage capacity.

cihly
2.4.2012
Ing. Pavel Heinrich, HELUZ cihlářský průmysl a.s.

Clay bricks are one of the most common material used mainly in the contruction of residential buildings. We can say that masonry is a kind of standard of building design, as all other materials are being compared with brick masonry. Few years ago, there were only full bricks. In connection with the development requierements of heat transfer coefficient of the wall, the structure of the bricks is changing. Currently avaliable bricks are suitable for one-layer masonry of passive houses. The article presents an overview of the development of bricks and outlook for the future.

pasivní domy
26.3.2012
Ing. arch. Werner Friedl, certifikovaný projektant PD Bergstraße 12, D-86559 Adelzhausen

The design concept of passive houses is not a contradiction. On the contrary, higher quality of architecture is likely to increase the sustainability of a passive house. Architect Werner Friedl presents the passive house in words and pictures some of his built passive houses in a practical design, including construction details.

19.3.2012
doc. Ing. Jan Kaňka, Ph.D., člen TNK 76 Osvětlení, ČKAIT Praha

The formula specified in CSN 730581 for calculating the solar declination will over the years increasingly diverge with reality. At present, its relative inaccuracy of the four-year average of the declination for noon first March is just under 8 minutes of arc. Important information for assess the insolation of buildings raised at the conference Current Issues of lighting and solar access of buildings.

12.3.2012
Ing. Monika Michálková

During the reconstruction of objects there may be situations where the noise in outer area cannot not reduced (traffic noise etc.) and it is necessary to ensure comfort at least in the internal protected area of the building. This can be achieved by using adequate building façade – especially adequate windows. Soundproof windows should be designed on the basis of traffic noise in the locality.

úsporné žárovky, výbojky, diody
5.3.2012
Ing. Petr Žák, ČVUT FEL, Praha

The article deals with the basic trends in electric light sources and phasing out inefficient energy sources from the market. The article provides a very good overview of the sudden development of specific performance of each new promising types of light sources, whether they are electrodeless source or light emitting diodes LEDs.

27.2.2012
Ing. Roman Šubrt, Ing. Pavlína Charvátová

As the cheapest and least problematic solution of thermal insulation for most buildings is the external thermal insulation composite system (ETICS). It is composed of the adhesive, as well as thermal insulation, mostly in the CR mineral wool or expanded or extruded polystyrene. These types of thermal insulation are usually anchored by plugs and all these parts are covered by the adhesive layer with reinforced fabric and the final render. For this system has recently been shown that the points of the plugs are problematic.

20.2.2012
Adam J. Cohen, Překlad: Ing. Petra Šrubařová

The first public school in the U.S. in the passive standard (K-12) was completed in November 2010. Passive house certification from the American Passivhaus Institute (PHIUS) was received in February 2011. The whole development project was quite long, so it is presented only briefly with the focus of our server. Article is provided in translation with the kind permission of the author.

6.2.2012
Vlastimil Růžička, redakce

The city of Olomouc is the owner of an interesting low-energy building for education center Sluňákov with a focus on developing the relationship between man and nature. Construction was awarded the Grand Prix of architects in 2007.

30.1.2012
Ing. Renata Straková, Ing. Josef Knob

Regular inspection is focused to the boiler, smoke flue and accessories condition, its security and regulation. In addition to the technical condition and maintenance, the documentation, operating instructions, manuals and other documents are under inspection. It quantifies the overall boiler efficiency of measurement results, sets reference respectively minimum boiler efficiency and suggests possible actions.

30.1.2012
Ing. Jaroslav Vychytil, ČVUT v Praze, Fakulta stavební, katedra konstrukcí pozemních staveb

In last time popularity of wood-based structures is increasing. Most parameters in the design phase can be calculated using known procedures, but the acoustics is a problem with the theoretical determination of sound reduction index of wooden structures just, because there are the only reliable methods to determine transmission loss of silicate-based structure. In this paper is presenting the calculation method used to determine the sound reduction index of timber floor structures with visible beams.

19.12.2011
Ing. Renata Straková, Ing. Josef Knob

When heat and energy assessment of existing buildings it is often a problem to determine the heat transfer coefficient U. In many cases it is possible to use a relatively simple measuring device. The device is designed only to measure heat transfer coefficients for vertical facade structures. It could be alternatively used for horizontal structures such as ceilings and floors as well.

12.12.2011
doc. Ing. Aleš Rubina, Ph.D., Ing. Olga Rubinová, Ph.D., Ing. Zdeněk Tesař

The article builds on previous text: Modeling of physical phenomena 1 - evaporation of water level and deals with the design and evaluation of physical phenomena when applying a controlled dehumidification of pool halls, rooms, etc. Design air handling unit is similar to existing solutions used in practice, supplemented by mathematical insights to simulate different states and setting the central dehumidifying equipment. In conclusion it is stated percentage rated the potential savings in the optimal operation of these facilities.

31.10.2011
prof. Ing. Jan Tywoniak, CSc., ČVUT Praha, pracoviště UCEEB

This paper deals with changes in the newly revised technical standard for building thermal performance in terms of ventilation and distribution of air in the building. This paper describes the formulation of requirements, when it is necesary to guarantee a quality of indoor environment and also minimize the energy consumption of ventilation. Attention is also paid to disseminating of air into leaks in the facade or roof.

31.10.2011
prof. Ing. Rostislav Drochytka, CSc., Ing. Jiří Zach, Ph.D., Ing. Bc. Jitka Hroudová

This paper describes the results of research aimed at studying the real hygrothermal behaviour of different types of cellular concrete products for masonry structure, particularly in terms of thermal characteristics depending on temperature and moisture content of the material.

24.10.2011
Ing. Vladan Panovec, Ing. Jiří Šála, CSc.

Calculations of heat transfer through soil according to ISO 13370 [1] and EN ISO 10211 [2] are rare. They stands out not only for the specific subject of interest, but also for a completely different philosophy of the calculation for determining the physical quantities. It is clear that this is unfortunately in conflict with the definitions and in conflict with real physical phenomenons. We try to approach the reasons for this assertion.

3.10.2011
doc. Ing. Richard Nový, CSc.

The author is concerned with the design of flexible placing and the explanation of resonance effects in a flexible element of one-mass and two-mass placing machines on the basis of theoretical analyses and practical experiences. He highlights problems regarding rotational machines placed flexibly due to high excitation frequencies to be used for significantly lower excitation frequencies. He points out of the necessity of cooperation between the designer of the machine flexible placing and the building safety engineer in cases of light construction structures of floors and ceilings.


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