Issue 3/1997

A summary of results from the development of axial-flow fans for longitudinal ventilation of tunnels is presented. The construction of these fans was described in VVI1/97, pp. 37 - 38.

The paper deals with merits and drawbacks of plastic piping applications. Basic characteristics of plastic pipes are given and on their basis the usability of plastic piping is discussed.

Economical operation of a cooling device in air-conditioning application with water cool storage is described. An example of numerical solution is presented.

The paper deals with smoke spreading in a building which is on fire. The effect of building ventilation and zoning on the fire development is described. More details about fire propagation in a multi-fIoor building and a church are given.

Construction arrangement of squirrel-cage induction motors (also ca/led motors with short-circuit armature) is explai­ned in this paper.

The paper deals with operating characteristics of squirrel-cage induction motors, three-phase and single-phase res­pectively.

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The paper deals with the project of ventilation in a new painting shop of the Škoda factory. The requirements of foreign investor on the project documentation, the selection of air handling elements and the realisation of the project are described. A brief description of the proposed air handling equipment and energy balance is enclosed.

Before building a new heating system or reconstructing a boiler room the decision about heat source must be taken. The paper aims to make the choice of energy source easier, particularly for the householders without natural gas supply.

Energy conditions in a suction system are discussed with respect to the cavitation properties of a pump. A general instruction for the static suction head evaluation is described. The static suction head determines the insta/lation of a pump in terms of its height above the lower reservoir level. The evaluation is demonstrated on three practical examples.