English

A new parametrical model for the prediction of the thermal performance of the earth to air heat exchangers is presen1ed. The system consists of an earth tube, buried in the ground, through which ambient or indoor air is propelled and cooled by the bulk temperature of the natural ground. The proposed model has been developed by analysing temperature data of the circulated air at the pipe's outlet using a systematic parametrical process.

In France, air conditioning of offices is often required especially in areas with high noise levels and in the Mediterranean climates. Evaporative cooling systems appear able to give a cost effective solution to the growing demand for summer comfort: hence, the CSTB and Gaz de France are currently conducting a joint research on the efficiency of such systems. On the basis of a comfort criteria, this have been done by computer simulations taking into account different kinds of systems, buildings, and climatic areas.

This paper deals with the thermal performance of an earth to air heat exchanger for cooling and heating purposes. The cooling system consists of an earth tube buried in the ground through which ambient air is propelled and cooled by the bulk temperature of the natural ground. Fresh or indoor air can be circulated inside the tube. A new, more accurate, transient, implicit, numerical model based on the coupled and simultaneous transfer of heat and mass into the soil and the pipe has been developed.

The present paper deals with the cooling potential of earth to air heat exchangers. The cooling system consists of an underground pipe laid horizontally where ambient or indoor air is propelled through and cooled by the bulk temperature of the natural ground. The dynamic thermal performance of the system during the summer period and its operational limits have been calculated using an accurate transient numerical model. Multiyear soil and ambient air climatic measurements have been used as inputs to the model.

There has been lack of fact-based knowledge for design and operation of supply-air filters for general industrial ventilation. A multi-company project within the Industrial Ventilation (INVENT) technology programme was started in 1994 to tackle this problem area which is assumed to be the most problematic one, according to the feedback from end-users in several industries, who also made the initiative to this project.

When talking about air-conditioning systems in buildings people argue with high energy consumption of those systems. They do not take into account that it is not possible in many climates to realise several indoor thermal conditions by merely opening windows.Within the framework of the research project SANIREV, sponsored by BMBF and ROM, the Hermann-Rietschel-lnstitute make tests about the use of window ventilation. For different roomloads and out-door-conditions the room conditions are determined. Now we got the first results.

A new, integrated method to calculate the energy contribution of night ventilation techniques to the cooling load of a building is presented in this paper. The method is based on the principle of "Balance Point Temperature" and permits the calculation of the energy required to cool a building to acceptable comfort conditions when night ventilation techniques are used. It also permits the calculation of the energy contribution of night ventilated buildings compared to conventional air conditioned buildings.

With the growth of living standards, there is an increasing demand for the cooling of living space. Rational energy use demands the use of alternative ways of cooling because the energy consumption of compressor cooling is high. In this article a new cheap and efficient paperboard compact heat exchanger and indirect evaporative cooling are presented.