Issue 4/2003

The authors fixed their attention on the description of the temperature and velocity fields on the water side of the desk type radiators, connected one-sidedly from above downwards and double-sidedly from above downwards with the so-called short and long (L ? 4H) radiators. With regard to the results obtained by mathematical simulation the authors give unequivocal recommendation concerning the connection of long radiators.

The article deals with some principles being of use in tasks which are aimed to decrease the content of moisture and its effects in historical interiors. A simple model including both properties of a moisture active material and experimental data of boundary layers of natural gravity buoyance has been used to prove a supplementary setting on fans and other simple artificial means to intensify the movement of interior air.

The article deals with the design of air shower for heat stress reduction of workers in hot workshops. The design of air shower is based on operational measurements of thermal conditions of the environment on the working place. The analysis of workers’ heat stress was made by using the WBGT-index. From the measured WBGT-index dependence on the airflow velocity, the airflow velocities, which are needed for obtaining a homogenous environment with the WBGT reference value, have been determined. Thus defined courses of velocities along the working place height have been applied for the design of an optimum air shower. The visualization of airflow by means of fog is used for verify of air shower influence upon the production technology.

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The Czech Republic is gradually taking over the system of approving, permitting and designing the products related to water supply and distribution, common in EU. This system is based on the fact that the products, as separators of oil substances or grease traps, are construction products and that they are handled in a way corresponding with this type of product. This means that the procedures corresponding with the appropriate product and design, European standards, laws and directions concerning products are being put into practice.

The aim of the contribution is to evaluate the limits of economical utilisation of co-generation equipment consisting of gas micro-turbine with generator for electric energy generation and of combustion products boiler for heat generation. It concerns the verification of calculation procedures used for data acquisition needed for advantageousness evaluation of investment put into the technically perfect however high-priced equipment from the point of investment view.

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The article deals with factors leading to the origins of legionella infection and proposes the prevention possibilities and minimisation of legionnaire’s disease origins. The article is destined first of all for the professional technical public with the aim to clarify the problems, gain inspiration for technical solutions and measures leading to the elimination of this risk in the drinking water distribution network and in this way in all equipment connected to this network.

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.