Issue 4/2010

Authors deals with influence upon heating capacity and energy saving on application reflective and thermo-reflective plastic wrap inside the heating surface. The article purveys both theoretical analysis and results which were obtained through an experiment.

The article includes risks concerning the determination of the real value of the heat transfer coefficient in construction structures that is necessary for the calculation of the building energy efficiency. There is described the non-destructive method of the heat flux measurement and the determined methodology for the method application.

The need of a partial value of the delivered energy needed for the domestic hot water preparation (hereinafter the “DHW”) is showing one of calculation factors specifying the building energy demand in sense of determination the total energy delivered in the building. Authors describe the principle of the calculation procedure regarding the delivered energy serving for preparation of DHW in sense of use with respect to requirements of Decree 148/2007 Coll. The contributive issue is presented by the clear arrangement of DHW specific consumptions.

The author compares theoretical assumptions of the electric energy generation and its real generation in the implemented photovoltaic power plant in his contribution. Specified summaries of data can serve both for possible future investors considering the construction of a similar equipment and for a broad professional public.

Price of a filter is inflected by many users and customers of air filters nowadays in the CR in all cases and became the decisive point for the selection of the supplier or the manufacturer. However, the tendency to perceive the price of the air filter solely as an immediate cost for the purchase without any other contingencies is currently very short-sighted and uneconomical. The aim of this article is to inform the public of the operation and economic relationships of the air filtration and to offer the instruction of how to ensure the energy saving and the overall reduction of operation costs. Videlicet how to operate the air filtration effectively. Let us include the notion “price of filter” in broader conjunctions and let us speak of “price of the air filtration”.

The author describes reconstructions of air-conditioning equipment in the building after the year 1989 in the second part of his article. He states changes performed in the central air treatment unit as well as subsidiary air conditioning machine rooms in individual floors. Even the concept of newly installed equipment resembles at the first glance to the original one, negative affects to the air conditioning functionality are pathetic. The unconsidered modernization of the equipment and certain fatal designers’ faults cause the absolutely insufficient function of the reconstructed air conditioning. The exhaust of the condensing heat from cooling units that was not fully solved and insufficient cooling capacity lead to the equipment devastation. The stated event should serve as a warning to designers vis- -vis unconsidered reconstructions of the formerly operative equipment.

This article includes fundamental information concerning displacement ventilation. It discusses its advantages, disadvantages and limitations. It describes the methods of the system design. The following section deals with experimental measurement taken in the chamber, which represents an office area. The experiment shows that the greatest impact of thermal comfort is on the vertical temperature gradient. The results of the experiment are compared with various design methods and according to them are recommended the most accurate method of the displacement ventilation design. The results of the experiment are also compared with the values obtained from CFD simulations. The comparison shows the accordance between the measurement and the imulation.

Authors are engaged in examining the quality of the environment inside the historic assembly hall during the cycle of graduation ceremonies in their contribution. The proper measurement of parameters of the inside environment took place during the examined period of time. Concurrently, such parameters were registered with sensors of the building monitoring system. The model of the assembly hall was modeled (created) in simulation program BSim2008. The aim of authors was to verify whether an acceptable thermal comfort of the inside environment has been achieved during graduation ceremonies in the assembly hall. The assumed percentage of dissatisfied audience increased up to the value < 15% since 10:00 a.m. in spite of the fact that the air temperature accomplished the designed parameters.

Autor deals with burning of alternative biomass in his artikle. He presents own practical results of his research and alternative pellets measurements at 24 kW boiler heat output. He provides a valuable recommendation for the technical practice too.

The author states forms of references to technical standards in legal regulations in the third conclusive part of the serial on technical standards and legal relationships of such standards to the Czech legislation. He explains fundamental methods, by which references to technical standards are used for purposes of obligation in the Czech legal environment, in the article. These, above all, are references in legal regulations themselves. In this case is being used the possibility of the direct quotation in the legal regulation on one hand, references to standardized values or eventually by specifying the list of standards in the annex, on the other hand. Further, standards are regularly specified as binding conditions in the pronouncement of the administrative body decision or in conditions of the obligatory statement. The author draws the attention in this part that such a procedure is not only incorrect but even illegal in cases of specific legal regulations. The third form of references to technical standards is the reference specified by either contractual party as a requirement for the fulfillment of the subject of the contract. Any contract is a manifestation of the free will of contractual parties and the assumption of such obligation by the designer is therefore the intentional action including any and all consequences ensuing therefrom on the contrary from both preceding forms.

The author deals in his article with an important information regarding a new legal regulation, in which rules concerning the fire safety conditions at the operation of stacks, combustion gases ducting and fuel consumers shall be specified from the beginning of the year 2011. The Governmental Decree no. 91/2010 Coll., shall not only replace the 30 years old (and obsolete) Decree no. 111/1981 Coll., on cleaning stacks but it shall bring a modern and more complete access to the operation of combustion gases ducting paths. The decree includes newly adjusted conditions for inspection and cleaning combustion gases ducting, same as terms of inspections and cleaning combustion gases ducting including the collection of solid polluting particles and condensate and newly determined terms for cleaning fuel consumers. Concurrently, the Governmental decree appoints rules for revisions of combustion gases ducting and their protocol elaborations. Detailed technical rules elaborated by the Association of Chimney Sweepers of the CR and registered under the Economic Chamber of the CR are initiatively prepared for this long-term expected legal regulation.

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