Issue 1/2003

The article represents an integral information on the course and character of the heating period 2000/2001 in Prague. From the climatic quantities measured at the observatory Prague-Karlov the values of quantities were determined necessary for the calculation of the heat demand for heating and the climatological data illustrating the weather character of this period in the Czech Republic.

The article deals with possibilities of floor convectors connection to single-tube horizontal heating system by the by-pass manner. The authors present the experimentally found out heating output changes of converter connected by different connection manners.

At first the author deals with general problems of administrative buildings air conditioning. In further parts the author devotes his attention to individual types of façades with high portion of all over glazing and indicates possible solutions of air conditioning.

The article informs the readers in a clearly arranged form about the calculation of wood mass accessibility for the heat source and gives the recommendation for the determination of the biomass transport limiting distance in the form of an example.

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The article deals with advantages of laminated plastic tubes used in distributing piping of cold water and warm service water. The piping shows lower values of linear expansion, walls rigidity and contributes to decreasing the number of supports. It is also not possible to disregard the higher piping flow capacity bringing specific savings when installing more extensive systems.

For design of pipe and duct dimension is most frequently used friction factor – for each section more times. Inside water pipes and air ducts HVAC installation are flow conditions in transition field, where friction factors are presented in terms of Reynolds number and relative roughness. As most accurate is used implicit Colebrook-White equation, for its solution is necessary iterative procedure. For technical application has been adopted number of easier to use equations, which results are many times very different. The contribution deals with critical comparison of the f– factor based on calculation of deviation from Colebrook-White equation and provide explicit equation for explicit calculation of friction factor.

The article describes the basic physical principles of the operational temperature determination in the heated space and the instruments by means of which it is possible to model mathematically this parameter describing the inner environment. The Hefaistos programme meant for static modelling and the ESP-r programme meant for dynamic modelling are demonstrated. In conclusion the Czech and International Regulations, in which the evaluation of the inner environment by means of operational temperature is used, are indicated.

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 paper describes the computer modelling and simulation work that was carried out to support the design of the new Indonesian Jungle pavilion in Prague Zoo. This pavilion will be basically a very large transparent (acrylic) dome maintaining a warm and humid jungle-like indoor environment. Problematic issues include very high solar gains in summer, very high heat losses in winter, requirements for high relative humidity of indoor air, and potential condensation against the roof.

The contribution deals with the control of thermal environment parameters according to indices PMV, PPD and DR introduced in ČSN EN ISO 7730. The author presents the design of the control system for technical equipment enabling the adjustment of air temperature and also the adjustment of walls temperature.