Issue 1/1998

The paper presents time behaviour of drying applied to building materials. A procedure for building construction drying is recommended preventing cracking and destruction risk. Suitable devices for moisture disposal from flats and houses are Iisted.

The papers deals with evaluation of next 10 filtration apparatuses determinated for indoor air cleaness and IAQ improvement. Dust collection efficiences of the air cleaners have been evaluated. Air flows (air capacities), noise levels and for some cleaners ozone concentrations and light negative ions concentrations in the air have been measured too.

Results from numerical FEM stress analysis of a pipe section with expansion S-bend are presented. Two methods were compared to each other: PIPE (approaching the pipeline as mass line) and SHELL4 (taking into account the pipe cross section).

"Safety devices for central heating and hot service water systems"

The paper deals with chemical fuel cells, their principles and materials used for their production. Individual types of cells developed in the world are described and their commercial applications are presented. The advantages of these cells are high efficiency, low noise and extremely low pollution. Fuel cells enable the most environmentally friendly utilisation of fossil fuels.

The paper presents experience with a single-pipe heating system applied during the reconstruction of a multi-storey house. Implemented methods, design and constructional details are described. Information given in this paper is very useful for designers and engineers dealing with similar problem.

The paper deals with the influence of central heat supply network on the output of heating appliance. Analysis of heat output change from mass fIowrate variation in primary or secondary pipe network is presented.

The paper deals with optical and thermal properties of clear float glass, wire glass and multi-Iayer polycarbonate materials which are used for skylights. Merits and drawbacks of these materials are discussed with respect to the maximum energy saving and thermal comfort.

Special regulations for electric devices in explosion risk environment are presented.

The issue of bypass in hydrodynamic pumps folio ws up the previously published information concerning the f10wrate control of recirculating pumps for hot water systems. This paper presents examples of bypass application in starting and operating periods of hydrodynamic pumps. ft also describes the bypass as a device protecting centrifugal pumps from overheating when operated at very low flowrates.

Results from measurements of working environment parameters in locomotive cabins are presented.

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