Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "temperature fluctuations" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-6 z 6
    Tytuł:
    Mean and turbulent thermal fields due to film cooling via an eddy heat diffusivity closure
    Autorzy:
    Karcz, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1933190.pdf
    Data publikacji:
    2006
    Wydawca:
    Politechnika Gdańska
    Tematy:
    v2- f-ko-Eo model
    turbulent heat flux
    temperature fluctuations
    film cooling
    Opis:
    The two-equation level of turbulent heat flux modelling is considered for application in film cooling instead of the turbulent Prandtl number concept. The investigations involve numerical analysis of mean and fluctuating temperature fields near the coolant injection inlet. The results of the implemented coupled v2- f-k0-E0 model are compared with measurement data for a flat plate cooled with compound angle orientation of discrete in-jection holes. The results of numerical analysis agree very well with the experimental data. The coupled model offers a detailed picture of gas turbine cooling problems without using time-consuming, inherently unsteady models.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2006, 10, 4; 377-390
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of Temperatures in the Cold Storage of Finished Products
    Autorzy:
    Bogdanovská, Gabriela
    Stehlíková, Beáta
    Kačur, Ján
    Powiązania:
    https://bibliotekanauki.pl/articles/102539.pdf
    Data publikacji:
    2019
    Wydawca:
    Stowarzyszenie Inżynierów i Techników Mechaników Polskich
    Tematy:
    cold storage warehouse
    temperature monitoring
    temperature fluctuations
    statistical evaluation
    Kruskal-Wallis test
    Bartlett test
    Nemenyi’s test
    magazyn chłodniczy
    monitorowanie temperatury
    wahania temperatury
    ocena statystyczna
    test Kruskala-Wallisa
    test Bartletta
    test Nemenyi
    Opis:
    The analysis of temperatures in the cold store of finished products was performed due to the occurrence of temperature fluctuations. The analysis in the report was conducted using Kruskal-Wallis test, Bartlett test, Nemenyi’s test Statistical analysis of measured values in individual months. The relationship between the temperature in the cold store and the outside air temperature was investigated. Quality tools were also used in the thesis. The causes of temperature fluctuations were determined by Cause-Effect diagnostics. The relationship between the main causes was analyzed with Relation Diagram. Corrective measures were then determined to minimize the temperature fluctuations in the cold store.
    Źródło:
    Advances in Science and Technology. Research Journal; 2019, 13, 3; 54-66
    2299-8624
    Pojawia się w:
    Advances in Science and Technology. Research Journal
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of pressure fluctuations on the temperature during braking
    Autorzy:
    Topczewska, Katarzyna
    Zamojski, Przemysław
    Powiązania:
    https://bibliotekanauki.pl/articles/386606.pdf
    Data publikacji:
    2020
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    braking
    pressure fluctuations
    pad/disc system
    temperature
    Opis:
    The aim of this study is to develop the numerical–analytical model of frictional heating in a pad/disc system during braking including the pressure fluctuations, engendered by the pump in an anti-skid braking operation. For this purpose, the problem of motion and the one-dimensional thermal problem of friction for a semi-space/semi-space tribosystem were formulated and solved. Obtained solutions allow to calculate temperature distribution on the contact surface and inside the friction elements. Thermal analysis was performed for a metal–ceramic pad and a cast iron disc during one-time braking including the time-dependent, oscillating pressure. The influence of amplitude of pressure fluctuations on the temperature variations was investigated, especially on the value of maximum temperature achieved during braking.
    Źródło:
    Acta Mechanica et Automatica; 2020, 14, 2; 103-107
    1898-4088
    2300-5319
    Pojawia się w:
    Acta Mechanica et Automatica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Features of the surface water oxygen regime in the Ukrainian Polesie Region
    Autorzy:
    Aristarkhova, Ella O.
    Fedoniuk, Tetiana P.
    Romanchuk, Ludmila D.
    Latushynskyi, Sergii V.
    Kot, Iryna V.
    Powiązania:
    https://bibliotekanauki.pl/articles/1844315.pdf
    Data publikacji:
    2021
    Wydawca:
    Instytut Technologiczno-Przyrodniczy
    Tematy:
    correlation analysis
    dissolved oxygen
    fish
    oxygen regime
    pH
    seasonal fluctuations
    surface water
    temperature
    toxicity
    Opis:
    The research analyzed seasonal changes of the oxygen regime and related indicators on the example of water objects of the Ukrainian Polesie Region. The region shows different directions of economic use. Zebrafish (Danio rerio Hamilton–Buchanan) and the Prussian carp (Carassius auratus gibelio Bloch) were used as test objects to investigate survival responses. Dissolved oxygen (DO) concentration in water, pH values and temperatures were determined by standard methods. Based on research results, the main problems were determined pertaining to the oxygen regime of investigated waters, i.e. the increase in temperature and toxicity of the aquatic environment in the summer. A rather dangerous decrease in DO concentration, almost up to the levels of maximum allowable concentration (MAC) (4.10 mg∙dm–3 in group E1 and 6.07 mg∙dm–3 in group E2), was observed in August and it was typical for the reservoirs with a slow water movement. Flowing river waters (group E3) were eliminated due to their better aeration compared to other groups. The correlation analysis based on the presented data revealed a high and average degree of probable correlation between the DO concentration and water temperature, as well as an average degree of correlation with general toxicity determined on sensitive species of D. rerio, and in group E1 on the persistent species C. auratus gibelio as well. The interrelations and equations of the rectilinear regression can be used to predict the oxygen regime of the waters investigated and other surface waters having similar problems.
    Źródło:
    Journal of Water and Land Development; 2021, 49; 104-110
    1429-7426
    2083-4535
    Pojawia się w:
    Journal of Water and Land Development
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spatial and seasonal variability of sub-daily water temperature dynamics in the lowland agricultural catchment of the Wkra River
    Autorzy:
    Skorupa, Weronika
    Łaszewski, Maksym A.
    Powiązania:
    https://bibliotekanauki.pl/articles/28411638.pdf
    Data publikacji:
    2023
    Wydawca:
    Instytut Technologiczno-Przyrodniczy
    Tematy:
    river water temperature
    thermal fluctuations
    Mazovia
    Central Poland
    hourly variations
    thermal conditions
    Opis:
    The paper concentrates on seasonal and spatial variations of sub-daily water temperature dynamics in lowland agricultural streams. Temperature monitoring was carried out in 24 sampling sites distributed along the tributaries of the Wkra River during the hydrological year 2021. Statistical analysis of the obtained data documented the highest water temperature dynamics in the morning, from 5:00 to 9:00 CEST, while the lowest - from 14:00 to 18:00 CEST. Seasonally, greater water dynamics were noted in the winter, expressed by a coefficient of variation reaching up to 100%. Spatially, the highest dynamics occurred in sites with the lowest proportion of riparian vegetation, while the lowest dynamics was related to higher catchment area. In the winter, the minimum daily values were recorded most frequently in the morning hours, while maximum values in the afternoon. A similar pattern was observed in the summer, but with much lower dispersion of the relative frequencies. It was found that in the winter, the dominant influence on temperature dynamics was exerted in the upstream catchment area, while in the summer, a negative relationship with riparian shade was marked. The findings suggest that the presence of riparian vegetation reduces diurnal dynamics of water temperature and is simultaneously extremely important in prolonging the duration of optimum fluctuation, responsible for the proper development of poikilothermic organisms.
    Źródło:
    Journal of Water and Land Development; 2023, 59; 153--163
    1429-7426
    2083-4535
    Pojawia się w:
    Journal of Water and Land Development
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Trends and fluctuations of river ice regimes in the Prypiat Basin, within Ukraine
    Autorzy:
    Gorbachova, Liudmyla
    Afteniuk, Oleksandr
    Khrystiuk, Borys
    Lobodzinskyi, Oleksandr
    Powiązania:
    https://bibliotekanauki.pl/articles/2201937.pdf
    Data publikacji:
    2023
    Wydawca:
    Instytut Meteorologii i Gospodarki Wodnej - Państwowy Instytut Badawczy
    Tematy:
    ice phenomena
    air temperature
    Prypiat River
    homogeneity
    stationarity
    cyclic fluctuations
    tendencies
    Opis:
    Information about the formation, destruction, and duration of river ice regimes is especially important for hydropower, shipping, fisheries, etc. Research into modern trends in river ice regimes and their spatial and temporal fluctuations is essential, especially in a changing climate. This study examines the trends and fluctuations of air temperature and ice regimes based on series of observations in the Prypiat River basin within Ukraine. Air temperature data from 17 meteorological stations and ice data from 29 water gauges were analyzed. A complex analytical approach involving statistical and graphical methods was employed. The Mann-Kendall statistical test, mass curve, residual mass curve, and combined graphs were used in the study. In the Prypiat River basin within Ukraine, observations of mean monthly air temperature, ice occurrence, freeze-up, and their duration are homogeneous (quasi-homogeneous) and stationary (quasi-stationary). The quasi-homogeneous and quasi-stationary characteristics are explained by the presence in the observation series of only increasing and decreasing phases of long-term cyclical fluctuations, which are incomplete. The trends of air temperature and ice regime correspond strongly, indicating the defining role of air temperature in the formation of ice occurrence and freeze-up. Since the end of the 1990s, the warming phase of air temperature in the autumn-winter period determines the appearance of ice and freeze-up later in the year. In March, the warming trend in air temperature, which began after 1988, determines the freezeup, break-up, and disappearance of ice earlier in the year. Thus, the duration of ice and freeze-up on the rivers has decreased.
    Źródło:
    Meteorology Hydrology and Water Management. Research and Operational Applications; 2023, 11, 1; 1--14
    2299-3835
    2353-5652
    Pojawia się w:
    Meteorology Hydrology and Water Management. Research and Operational Applications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-6 z 6

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies