Issue 1/2011

Author has analyzed thermal performance of solar collector as its capability to produce a heat gain throughout the year and has evaluated various types of solar collector with different efficiency and incidence angle modifier both for aperture area and gross area. Author, on the basis of analysis, has proved that flat designation of certain type of solar collector as more or less efficient than others cannot be realised without knowledge of basic parameters (efficiency and IAM curve) and considering a particular case and particular purpose of evaluation (operation temperature, evaluation based on aperture or gross area).

Authors deal with noise circular control damper which was attested experimentally. At the same time there is allowed groundwork adopted from ASHRAE covering witj noise of oblong control damper. At the close they present method to také connection between pressure losses of control damper and generated aerodynamic soud pressure level.

Authors deal with the calculation and the experimentally determined character of the air flow in the vicinity of the swirl diffuser in their contribution. The purpose of the experiment is the verification of periphery conditions entered in the CFD calculations with use of the simplified model of the supply element. Final velocity profiles obtained throughout the CFD are compared with experiments.

Authors show a very complex access as concerns the optimization of shading the administrative building in their article. They present the proposal of suitable shading (and its operation) that shall ensure both sufficient natural lighting without any glare and minimal heat gains during the summer period. The detailed energy balance of the space makes the tool for this proposal together with the detailed calculation of the direct and indirect lighting elaborated in the formof the computer aided programand completed with the visualization in the Ecotect + Radiance program.We believe that this article shall be contributive both in the detailed elaboration of the lighting and heat gains problems, and its practical application with respect to the real proposal.

The additional glazing loggias (enclosed balcony) in panel houses can substantially affect the energy balance and inside environment inside individual apartments. Effects of glazing are not quite definite and shall be derived from the specific structural design, original properties of the building as well as the method of its operation and behavior of users. Detailed simulation methods (Software IES – <VE>) analyze several model occurrences of glazed loggias and endeavor to express the potential energy economies (savings) and certain influences to the inside environment of adjacent occupied rooms, in the specified study.

Authors inform about the reverse use of heat and heat pumps in the building of Aquapark Čestlice in their article. They provide a summary of the building size and used technologies. They even do not cloak problems arisen during the construction implementation.

Authors of the article describe the actual situation of the Slovak legislature regarding the evaluation of buildings from the energy viewpoint. Firstly, it concerns the process of certification, which is concluded with the issuance of “Building Energy Label”, in which evaluations of individual areas of consumptions (heating, warm service water heating, ventilation with air conditioning and lighting) are marked in addition to the total energy building evaluation. The Energy Label includes the value of the annual specific consumption of primary energy and annual specific CO2 emissions. The Energy Label is analogical to the Czech “Certificate of Building Specific Energy Demand”. Secondly, it concerns the building energy audit, which serves for the evaluation of projects with respect to the improvement of their specific energy demand. Similar services are governed by Act no. 177/2006 Coll., and Decree no. 148/2007 Coll., in the Czech Republic.

Basic principles how to design radon preventive measures in dependence on the radon index of the building are presented. In more detail requirements for radon-proof membranes, sub-slab ventilation, air gap ventilation and indoor air ventilation are described.

Authors summarize the scientific knowledge based on the research of solid aerosols flow and their deposition in the human breathing tract with use of the computer flow modeling in the article. It is impossible to model the whole breathing tract with the present methods of computation; therefore the deposition was examined separately inside upper breathing airways and lower breathing airways until the ninth bifurcation. The used geometry has been modified according to a live human being CT scanning and it achieves up to the 9th. generation of the breathing tract bifurcation. While the upper breathing tract (the modeling the nose flow) serves as an effective filter of greater particles; the mechanism of deposition smaller particles inside the lower breathing tract, differs. There has been shown from calculations of the entire (closed) breathing cycle that the deposition of particles occurs not just at the breathing in but at the breathing out, too. Therefore, it is necessary to analyze the entire breathing cycle, not only the stabilized situation at the breathing in.

Sanitary taps and to the lesser extent also other metal products situated at the end of plumbing are the most common sources of nickel in drinking water. For this reason and because of various water stagnation times, the concentration of nickel in one sampling point can vary within range of several orders of magnitude and after stagnation may reach peak values up to 500 ?g/l, i.e. more than 20 times higher than current limit value (20 ?g/l). Such single oral nickel dose can provoke manifestation of systemic contact dermatitis in some nickel-sensitive individuals, which represent about 5 % of population.