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Постійне посилання колекціїhttps://dspace.nuft.edu.ua/handle/123456789/7522
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Документ A study of water ice formation and melting processes on vertical cooled pipes(2016) Zasiadko, Yaroslav; Pylypenko, Oleksii; Forsyuk, Andriy; Gryshchenko, RomanThe use of cold accumulators based on the principle of water ice formation on the cooled surfaces during off-peak periods and water ice melting during on-peak periods is an effective method of electricity bills reduction. Within comparatively short periods of on-peak demand a noticeable amount of thermal energy related to ice melting is to be released, it becomes clear that not only sizing of ice accumulators based on balance calculations is actual, but also the determination of time periods of ice accumulation becomes critical. This work presents an experimental unit for obtaining data on the ice formation on the vertical cooled pipes and later on to continuously register data on the ice thickness diminishing at the regimes of ice melting when cooling of pipe stops. The data for ice formation and melting for some regimes have been presented and analyzed. The data form the base for deriving semi-empirical correlations allowing to determine time intervals necessary to generate of water ice layers of given thickness.Документ 3-D modeling of water flow and cooling down within the temperature range close to inversion point(2016) Gryshchenko, Roman; Zasiadko, Yaroslav; Forsyuk, Andriy; Pylypenko, OleksiiThe research and simulation of heat transfer during water refrigeration in the experimental section close to the vertical pipe which is cooled down considering abnormal character of water density change from the temperature in close to inversion point (+4°C) section were investigated. The graphs of water temperature velocity distribution throughout the height of experimental section were constructed and analyzed. The results obtained allow estimating the impact of water temperature that is closely situated to inversion point on the dynamics of water ice melting and generation as well as on the form factors of cold accumulators. Such software and analytical research will allow increasing effectiveness and efficiency at the heat and bulk transfer equipment engineering.