ANWENDUNG DER AKTIVEN ISOLIERUNG ZUR KLIMATISIERUNG VON FAHRZEUGEN AM BEISPIEL VON KABINEN MOBILER LANDMASCHINEN

Abstract

In small spaces loaded heavily thermally, e. g. in the cabins of the mobile agricultural machines, it is difficult to develop favourable climatic conditions (temperature, humidity degree, air velocity, etc.) required for accommodating the operating personnel with the help of natural ventilation, especially in the case of a heavy load of solar radiation. In case of the latter solution, the volume ftow-rate required for natural ventilation will be too strong and accordingly, air velocities harmful for health will develop in the cabin. In this case, the so called 'active heat insulation' (air flow between two walls) provides favourable solution. Under the condition of active heat insulation, the volumeflow rate of the required fresh air flowing into the cabin will be considerably reduced, and this, in turn, involves the reduction of the local air velocities in the cabin and the improvement in the personnel's general health condition staying in the cabin. In the paper, the calculation procedure of the active heat insulation is discussed, and a numerical example is also given. The traditional and active heat insulations are compared to each other, and the advantages of the active heat insulation are analyzed. With the application of active heat insulation, favourable results were achieved not only in the air conditioning of the cabins of agricultural machines but with railway wagons, too.