Issue 2/2003

The aim of the contribution is to draw the attention of the technical community to the difficulty of the purposeful utilisation of condensation boilers assets used as heat source in central heat supply networks. It concerns the verification of calculation procedures used for data acquisition needed for advantageousness evaluation of investment put in the technically more perfect, however capital- more intensive equipment.

The author presents new knowledge concerning the level and frequency composition of noise generated in the direction inwards of flue gas ducting and stack. He indicates the possible calculation procedure of calculation of the acoustic power spectrum and determination of basic resonance frequencies of the system: boiler, flue gas ducting and stack. He draws the attention to the possibility of pure tones formation in the field of ultrasound.

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The problem of piping insulation comes to the limelight of our professional public interest. It is not only in connection with the Regulation No. 151/2001 Coll. which puts increased stress on piping insulation but also in connection with permanent pressure on economical use of energy. The two-part article will make us acquainted with used methods and ways of calculation of this physical phenomenon from the theoretical and practical points of view with regard to valid European standards.

The article presents relations enabling to create mathematical model of solar liquid collector. The procedure is described from two point of views; external absorber energy balance and internal energy transfer by fluid.

The article presents information about the construction execution of the Czech scientific station in Antarctic, about energy consumption, and the solution of energy supply of this distant building site, first of all from alternative sources. The station should be operated during seasonal (summer) operation and serves for working stay of up to 15 scientists. The station should have been constructed in Antarctic summer 2003, the reasons for the one-year delay of the construction are given in the article.