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EN
The paper presents the partial results of the multidisciplinary project assessing the ratio of biologically vital areas (RBVA) as an indicator in spatial planning of the housing estates in Poland. The article focuses on air temperature differences between the 18 housing estates characterized by different RBVA, different surrounding, the age of buildings, arrangement etc. The automatic measurements of the air temperature in each of estate were conducted from autumn 2008 to July 2010. They indicate that the warmest housing estates are those of the smallest participation of green areas (less than 20%), situated in the city centre but also those of RBVA c. 40%. The coldest are the estates of peripheral location but also those with higher participation of biologically vital area (up to 60%). The thermal differences between them reach 9.6°C in summer and 5.5°C in winter. The results point out the RBVA threshold of c. 45% above which the function of the natural environment in the city is not completely changed.
3
Content available O naturalnych i antropogenicznych zmianach klimatu
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EN
The paper presents natural and anthropogenic causes changes of the Poland’s climate on the base of the meteorological data. It is diffi cult to distinguish anthropogenic climatic changes from the natural ones. The change of climate conditions in the 20th century resulted from the change of the character of atmospheric circulation (cyclonic south-western circulation) especially during winter and autumn. The climatological and astronomical forecasts are the only forecasts regarding changes of the Earth’s climate in the 21st century.
PL
W artykule przedstawiono propozycję konstrukcji naczynia do ogrzewania wody do celów socjalnych. Jako czynnik grzewczy w zaprojektowanym systemie wykorzystano ciepło z obiegu wtórnego urządzeń chłodniczych. Uzyskane wyniki na urządzeniu prototypowym (rys. 4) pozwalają stwierdzić, że istnieje możliwość warstwowego ogrzewania cieczy wewnątrz naczynia. Dzieje się to wówczas, jeśli do miejsca wymiany ciepła dostarczana jest stale chłodna woda. Zaprojektowana konstrukcja umożliwia wykorzystanie niskotemperaturowych źródeł ciepła z obiegów chłodzących do ogrzewania wody, eliminując niebezpieczeństwo przeniknięcia mediów.
EN
In the contribution is submitted proposal of the vessel construction for water for industrial use. For heating is being used the secondary heat from the cooling system. More frequent utilization of this energy is limited of present by two facts: 1. The cooling devices contain toxic charge and therefore the pipeline for cooling medium passing through must not be in direct contact with the heated water for hygiene and safety reasons. 2. Sufficient thermal difference for effective heat sharing is possible only when the cool water is supplied to the place of heating. The suggested construction solves both these problems. The primary pipeline with ammonia is located on the container outer side into other heat-carrying protective medium. The inner arrangement provides the isothermal water stratification in container. In to the container is located the insert from non-conductive material with outer dimension smaller than the inner diameter of container. This enables formation of the slot filled by the heated water. Between the hot water in the slot and cold water inside the vessel creates the pressure difference, heated water rises into the upper part of the container and cold water is sucked into the slot from the bottom. Within the heating almost whole container volume is therefore reached steady thermal gradient between the heating and heated medium and maximum effectiveness of the heat sharing. After verification of the suggested construction the device prototype is manufactured enabling monitoring of the temperature course in various parts of the device in dependence on time. The temperature layout inside the container was monitored by five thermal sensors located in the vessel centre line in distance of 150 mm (Fig. 3). From the measuring results is evident the heated water stratification inside the vessel. To the heating point is continuously supplied water of initial temperature (Fig. 4) for 15 minutes. Nevertheless, from the measured temperature resulted that the cooling medium secondary heat is not utilized sufficiently. The maximum output of the device at the heating beginning is almost 5 kW. This it will be necessary to extend the heat-exchanging surface of the exchanger or to adapt the slot shape along the vessel periphery to reach lower flow rate of the heated water. The described device will enable after the suggested adaptation the effective utilization of the secondary heat of the cooling medium without risk of its penetration into the heated water.
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