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1

Surface Temperature Prediction Using Long Short-Term Memory – Case Study Java Island, Indonesia

Satriadi Alfi, Widada Sugeng, Prayogi Harmon

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 4

73--78

EN

We predict the surface temperature of Java Island in Indonesia based on a dataset of wind speed, surface temperature, and surface pressure from 2002 to 2021. Long short-term memory model is employed to predict the surface temperature in 2022. The predicted surface temperature corresponds to the seasons of Indonesia. The result shows a pattern between dry and monsoon seasons of Indonesia. The performance of the model is evaluated using root mean square error. The root mean square error in the land area is larger than the water area.

2

Investigating recent changes in the wind speed trends over Turkey

Gumus Veysel, Simsek Oguz, Seaid Mohammed

Acta Geophysica

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2023

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Vol. 71, no. 3

1305--1319

EN

The wind has considerable effects on the ecosystem and evaporation as an essential parameter of the hydrological cycle. Therefore, determining historical changes in the wind will help to specify these effect levels. Although there are studies on the determination of wind speed trends by several researchers in Turkey, it is necessary to investigate the changes in the trend structure with recent data. For this purpose, the trends of monthly surface wind speed data from 1970 to 2021 belonging to 199 meteorology observation stations in Turkey are determined in the present study. The nonparametric Mann–Kendall test and Sen’s slope method are used in the trend analysis accounting for serial correlation effects. The trend analysis results of wind speed data are evaluated temporally and spatially for seven geographical regions within Turkey. As a result of this study, a prominent part of stations in Turkey shows a decrease or significant decrease trend. In addition, as a result of comparisons made with previous studies, it is determined that the trend structure of the wind speed in the country has changed. In the annual and monthly wind speeds, it is observed that the number of stations has a "significant trend" decreased considerably.

3

A survey of applications of simple and multiple linear regression in wind power generation

Mbuli Nhlanhla, Mendu Bongumsa

Przegląd Elektrotechniczny

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2022

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R. 98, nr 3

32--35

EN

This paper presents the results of a survey on the application of simple and multiple linear regression in wind power generation research. Relevant publications were searched for, found, reviewed, and summarised. An increasing trend of number of publications on this topic was found. The main categories of publications forecasting of wind output power, forecasting of wind speed, and wind turbine generator temperature monitoring. The paper presents coincise summaries of publications and details the references identified, all of this in one repository.

PL

W artykule przedstawiono wyniki badań ankietowych dotyczących zastosowania prostej i wielokrotnej regresji liniowej w badaniach energetyki wiatrowej. Odpowiednie publikacje zostały wyszukane, znalezione, zrecenzowane i podsumowane. Stwierdzono rosnący trend liczby publikacji na ten temat. Główne kategorie publikacji: prognozowanie mocy wiatru, prognozowanie prędkości wiatru oraz monitorowanie temperatury generatorów turbin wiatrowych. W pracy przedstawiono zwięzłe streszczenia publikacji i wyszczególnienie zidentyfikowanych pozycji literaturowych, a wszystko to w jednym repozytorium.

4

Assessment of Hazard from Damaging Wind Gusts in the Siedlce Area

Radzka Elżbieta, Olszewska Eliza

Journal of Ecological Engineering

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2022

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Vol. 23, nr 7

192--196

EN

The average daily values of wind speed and wind gust speed in the years 2001–2018 in Siedlce were analyzed. In the study area, the frequency of individual wind directions was determined and, according to criteria set by the Government Centre for Security, the frequency of hazards from damaging wind gusts was evaluated. The following wind gusts were considered: >20 m/s, 25 m/s and 35 m/s. It was found that, in the Siedlce area, the prevailing wind direction was west-south-westerly (WSW), and the average annual wind speed in the long-term study period was 2.99 m/s. March, April and May were the months when the highest speeds of maximum wind gusts (>35 m/s) were recorded. Extreme wind gusts the speed of which poses a hazard to the environment, national economy as well as human life and health, occurred in both the cold and warm seasons of the year.

5

Reliability-Based Assessment of Galloping Instability of Thin-Walled Steel Beams

Nguyen Huu Anh Tuan

Civil and Environmental Engineering Reports

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2022

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Vol. 32, no. 2

23--35

EN

Galloping instability relating to cross-wind vibrations can be found in flexible and lightly damped structures. In the present paper, the reliability of a thin-walled steel beam in maintaining its galloping stability was examined using a probabilistic approach. The analysis considered random variation in the cross-sectional geometrical properties of the beam, the material elastic modulus, the structural damping and the wind speed. A large number of Monte Carlo simulations were performed with normal and Gumbel distributions applied to the random variables to determine the probability distribution function of the safety margin. The limit state is considered violated when the wind speed exceeds the onset wind velocity of galloping, resulting in the aerodynamic damping being greater than the structural damping. It was shown by a conventional codified safety factor method that the beam was robust enough for galloping stability. By contrast, the probability-based assessment revealed that the beam failed to achieve the target reliability index in case the coefficient of variation of wind speed was greater than 5%. The analysis results suggested that the code-satisfied slenderness of the beam should be reduced by a factor of 1.5-1.7 under the action of wind speed with a coefficient of variation in the range 30-40%.

6

The thermal characteristics of ACCR lines as a function of wind speed – an analytical approach

Zaręba Marek, Gołębiowski Jerzy

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2022

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Vol. 70, nr 3

art. no. e141006

EN

The paper has investigated the effect of wind speed on selected thermal characteristics of the contemporary ACCR line. As wind speed functions, heating curves, stationary temperature profiles, steady-state current ratings and thermal time constants, have been determined. The composite core (Al–Al2O3) and the Al–Zr alloy braid were modeled as porous solids. As a result, the physical model is composed of a solid cylinder and a hollow cylinder with different material parameters of the above-mentioned elements. The mathematical model was formulated as the boundary-initial problem of the parabolic heat equation. The problem was solved by the state-superposition of and variable-separation method. On this basis, a computer program was developed in the Mathematica 10.4 environment and the velocity characteristics sought for were plotted. The results obtained analytically were positively verified by the finite-element method in the NISA v.16 environment. The physical interpretation of the determined characteristics has been given.

7

Assessing the Impact of Wind Conditions on Urban Heat Islands in Large Australian Cities

Al-Obaidi Ilham, Rayburg Scott, Półrolniczak Marek, Neave Melissa

Journal of Ecological Engineering

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2021

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Vol. 22, nr 11

1--15

EN

Urban regions are well known to be warmer than the outlying surrounding regions: this phenomenon is termed an Urban Heat Island (UHI). Depending upon its severity, an UHI can influence human health, the condition of urban vegetation, as well as air and water quality leading to a general decline in the living conditions of the affected urban environments and residents. Some studies have shown that prevailing weather conditions, like wind patterns, can influence UHI magnitudes. These studies suggest that wind speeds may be inversely related to UHI magnitude. However, long-term and high frequency weather and temperature measurements are exceedingly rare, so the exact nature of the relationship between wind speeds and directions as well as UHI magnitudes remain unknown. In order to address this problem, this study investigates how UHI magnitudes in five Australian cities affect wind speed and wind direction. The results of this study revealed that urban–non-urban temperature differences are most pronounced under calm weather conditions. The UHI intensity weakened as wind velocity increased: strong significant negative correlations were found between the mean UHI intensity and mean wind speed magnitudes. The results show that the greatest UHI intensities are recorded when wind is weak (less than 2 ms-1), while the lowest magnitudes are found when wind speeds exceed 6 ms-1. Further, the results show that the critical wind speed value, above which the strength of the UHI is considerably minimized, is around 4–5 ms-1. In addition, the study shows that wind direction in each city is a critical driver factor that determines the intensity of the UHI effect. When winds originate from dry environments, they favour high UHI intensities at all wind speeds, while the winds from the ocean side of coastal cities tend to cool urban regions, reducing UHI intensities or even promoting the urban cool island formation.

8

Analysis of climate change and its potential influence on energy performance of building and indoor temperatures, part 1: Climate change scenarios

Firląg Szymon, Miszczuk Artur, Witkowski Bartosz

Archives of Civil Engineering

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2021

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Vol. 67, nr 3

29--42

EN

The subject of this paper is to analyse the climate change and its influence on the energy performance of building and indoor temperatures. The research was made on the example of the city of Kielce, Poland. It was carried out basing on the Municipal Adaptive Plan for the city of Kielce and climate data from the Ministry of Investment and Development.The predicted, future parameters of the climate were estimated using the tool Weather Shift for Representative Concentration Pathways (RCP). The analysis took into consideration the RCP4.5 and RCP8.5 scenarios for years 2035 and 2065, representing different greenhouse gas concentration trajectories. Scenario RCP4.5 represents possible, additional radiative forcing of 4.5 W/m2 in 2100, and RCP8.5 an additional 8.5 W/m2. The calculated parameters included average month values of temperature and relative humidity of outdoor air, wind velocity and solar radiation. The results confirmed the increase of outdoor temperature in the following year. The values of relative humidity do not change significantly for the winter months, while in the summer months decrease is visible. No major changes were spotted in the level of solar radiation or wind speed. Based on the calculated parameters dynamic building modelling was carried out using the TRNSYS software. The methodology and results of the calculations will be presented in the second part of the paper.

PL

Przedmiotem artykułu jest analiza zmiany klimatu oraz jej wpływu na charakterystykę energetyczną budynku i temperaturę wewnętrzną. Badania przeprowadzono na przykładzie miasta Kielce. Ich podstawą był Miejski Plan Adaptacyjny dla miasta Kielce oraz dane klimatyczne z Ministerstwa Inwestycji i Rozwoju. Przewidywane, przyszłe parametry klimatu zostały oszacowane za pomocą narzędzia Weather Shift dla Representative Concentration Pathways (RCP). W analizie uwzględniono scenariusze RCP4.5 i RCP8.5 na lata 2035 i 2065, reprezentujące różne trajektorie wzrostu stężenia gazów cieplarnianych. Scenariusz RCP4.5 reprezentuje przewidywane, dodatkowe wymuszenie radiacyjne wynoszące 4,5 W/m2 w 2100 r., a RCP8.5 dodatkowe 8,5 W/m2. Wyznaczone parametry obejmowały średnie miesięczne wartości temperatury i wilgotności względnej powietrza zewnętrznego, prędkości wiatru i wielkości promieniowania słonecznego. Wyniki obliczeń potwierdziły wzrost temperatury zewnętrznej w kolejnych latach. Wartości wilgotności względnej powietrza nie zmieniają się znacząco dla miesięcy zimowych, natomiast w miesiącach letnich widoczny jest ich spadek. Nie zaobserwowano większych zmian w poziomie promieniowania słonecznego i prędkości wiatru. Na podstawie obliczonych parametrów przeprowadzono dynamiczne modelowanie budynku przy użyciu oprogramowania TRNSYS. Metodologia i wyniki obliczeń zostaną przedstawione w drugiej części artykułu.

9

Scenarios to reduce evaporation from class A evaporation pan by using windbreaks

Oribi Mustafa O., Abdulkareem Asraa K.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2020

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Vol. 29, No. 3

343--354

EN

Evaporation from reservoirs and lakes is an important processes frequently occurring in dry, hot regions such as Iraq. In order to preserve the environment and to reduce the amount of evaporation from open water bodies in this study, simulation was performed to reduce evaporation from evaporation basin class A by using windbreaks natural (Conocarpus trees). Three basic scenarios were made that depended on the values of the atmospheric elements affecting the evaporation process in summer according to the modified Penman equation for the conditions of Iraq, the climate factors are temperature, solar radiation, wind speed, dew point, and the effect of the number of windbreaks and their height was also introduced in sub- scenario. Experiments have shown that the best sub-scenario for all basic scenarios is when the windbreaks are placed in a direct direction to the wind blowing on the evaporation basin in the form of three rows, each row contains three trees where the windbreaks are in case cross and the height of the trees is 100 cm and the distance between each tree and another, and between each row and row 15 × 15 cm, the results of this subscenario recorded the highest rate of evaporation reduction up to 35% of its original value before using windbreaks.

10

Indian Ocean wind speed variability and global teleconnection patterns

Sinha Mourani, Jha Somnath, Chakraborty Paromita

Oceanologia

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2020

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No. 62 (2)

126--138

EN

The influence of the local sea surface temperature (SST) and remote ENSO (El Niño-Southern Oscillation) indices on the wind speed (WS) data were explored for the Indian Ocean region. Relationships among the parameters were studied using spatial correlation plots and significant correlation ranges. Two months (July and January) representing opposite monsoon phases were selected for analysis for the period 1950-2016. There was a significant negative correlation between WS and SST over the Bay of Bengal (BOB) during July. Although different ENSO indices correlated differently in different areas of the Indian Ocean, the region off the coast of Sri Lanka was most significantly teleconnected. The southwest monsoon locally impacted the WS and SST relationship and the WS parameter was remotely teleconnected in both the monsoon seasons. Further empirical orthogonal function (EOF) analysis was applied on the 67 years WS data of the BOB region to extract the dominant mode representing maximum variability of the total variance. The temporal pattern of the first principal component (PC1) of WS data was linked to the North Atlantic Oscillations in January and the Atlantic Multidecadal Oscillation in July respectively. The continuous wavelet power spectra of the PC1 of WS showed significant regions in the 2-4-year band resembling the ENSO variability. Wavelet coherence applied between PC1 of WS and the ENSO indices showed greatest values for January in the 8-16-year band and for July in the 0-4-year band. A close relationship was established between the WS variability in BOB and the ENSO indices.

11

Krytyczna prędkość wiatru powodującego zerwanie dachu budynku podczas burzy wiatrowej w 2017 r.

Chmielewski Tadeusz, Kaleta Barbara, Nowak Henryk

Inżynieria i Budownictwo

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2020

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R. 76, nr 6

290--292

PL

Oszacowano krytyczną prędkość wiatru w zdarzeniu zerwania dachu jednopiętrowego budynku podczas burzy wiatrowej. Obliczono ciężar konstrukcji i pokrycia dachu oraz oszacowano siły połączenia między murłatami i ścianami kolankowymi. Na podstawie porównania tych sił obliczono krytyczną prędkość wiatru, która jest znacznie większa od prędkości wiatru pomierzonych na stacjach meteorologicznych.

EN

The objective of the article is to estimate a critical wind speed in the event of a roof blow-off of a one-story brick building during a wind storm on August 11, 2017. The weight of the structure and roofing was calculated, and the strength of the connection between the rafter plates and knee walls was estimated. Comparison of both of these forces allowed for the calculation of critical wind speed that turned out to be much higher than the measured wind speeds at meteorological stations.

12

Estimation of critical wind speed on the basis of roof blow-off

Chmielewski T., Kaleta B., Nowak H.

Archives of Civil Engineering

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2020

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Vol. 66, nr 3

391--405

PL

W dniach 11-12 sierpnia 2017 r. nad Polską przeszła rozległa burza wiatrowa. Cała burza obejmowała obszar około 540 km od Wrocławia, przez Poznań, Bydgoszcz, wzdłuż Gdyni i Gdańska oraz część Wybrzeża. Z dużą siłą wiatru przeszła przez trzy województwa: Wielkopolskie, Kujawsko-Pomorskie i Pomorskie. Pomierzone prędkości wiatru osiągnęły 130 km/h, powodując duże zniszczenia na swojej drodze, a w jednej stacji synoptycznej, tj. w Elblągu prędkość wiatru przekroczyła 150 km/h. Maksymalne prędkości wiatru zostały pomierzone w następujących miejscowościach: Chojnice: 31.2 m/s (112 km/h), Gniezno: 34.8 m/s (125 km/h), Chrząstowo/Noteć: 36.0 m/s (130 km/h), Elbląg: 42,0 m/s (151 km/h). Ścieżka przejścia burzy była w przybliżeniu liną prostą, miała ponad 400 km długości i w trzech miejscach oddalonych około 70 km wiatr wiał z prędkością 100 km/, czyli burza spełniała kryteria burzy „derecho”. Burza wiatrowa spowodowała ofiary ludzkie i ogromne straty materialne opisane w pracy [8]. Celem artykułu jest oszacowanie krytycznej prędkości wiatru w zdarzeniu zerwania dachu jednopiętrowego ceglanego budynku podczas burzy wiatrowej w dniu 11 sierpnia 2017 r. W tym celu obliczono ciężar konstrukcji i pokrycia dachu oraz oszacowano siłę połączenia między murłatami i ściankami kolankowymi. Wzajemne porównanie obu tych sił umożliwiło obliczenie krytycznej prędkości wiatru, która okazała się znacznie większa od wartości pomierzonych na stacjach meteorologicznych.

EN

Types of wind storms in Poland and examples of economic damage, threats to human life and health caused by two extreme wind events are presented. Then, a house with the roof blown-off during the derecho wind storm in Poland on August 11-12, 2017, is considered. Based on the rafter framing of the house, i.e. wooden roof structure elements and roof covered, the weight of the roof is calculated. Two cases of the strong connection between rafter plates and knee walls are estimated. With the estimation of connection strength between rafter plates and knee walls, it was possible to calculate the total force required to blow-off the roof of the house. Next, an aerodynamic force acting on the house is calculated using pressure coefficients for a low-rise house with a gable roof. The pressure coefficients were taken from the Tokyo Polytechnic University aerodynamic database. The aerodynamic force acting on the roof blown-off was calculated for a low-rise building with a gable roof for similar ratios for length, width, and height. Three wind directions, for the unknown orientation of the building, were considered, i.e. the wind direction perpendicular, parallel, and oblique to the gable wall. By comparison, the aerodynamic force with the total force required to blow-off the roof of the house, it was possible to calculate the critical wind speed needed for the roof blown-off. This wind speed is much bigger than measured by meteorological stations on the path of the derecho.

13

Some effects of wind on ship’s manoeuvrability

Szymoński M.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2019

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Vol. 13, no. 3

623--626

EN

All ships experience an air and wind resistance while under way of sea, and they may experience adverse effects on wind while manoeuvring in harbours and limited waterways. The wind resistance is proportional to relative wind speed squared, wind direction and the projected windage area of the ship. The paper describes the effect of wind pressure into the ship’s superstructures and houses on ship manoeuvrability, in the range of the wind speed, for the ship which is with the large windage area. The above is one of the recommended information to be included in the ship’s manoeuvring booklet, as per IMO Resolution A.601(15). In sea practice, the manoeuvring characteristics in wind, as wind forces and moments, course-keeping limitation, and drifting under wind influence are fare from these estimated. The results obtained during the several years of practice in ship’s exploitation are included in this paper.

14

Wind Power as a Renewable Energy Source

Radzka Elżbieta, Rymuza Katarzyna, Michalak Anna

Journal of Ecological Engineering

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2019

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Vol. 20, nr 3

167--171

EN

The work presents a description of wind speed and direction in terms of using wind power as a renewable energy source. The wind power in Poland and at the Zawady EF was characterised. Observations were collected from 2002 to 2006 by an automatic meteorological station installed at the Zawady Experimental Farm (EF). Average monthly and yearly frequencies of winds blowing from individual directions were determined, and the average monthly wind speed was analysed. The most frequently recorded wind speed ranged from 2 to 4 m/s (light wind), and the least frequent winds blew at the speed of more than 10 m/s (strong wind). The cold season of the year saw winds blowing at the greatest speed (December, January and February), it being the lightest in the summer months (June, July and August). Wind rose analysis (2002–2006) revealed that at Zawady Experimental Farm, the westerly wind was the most frequent. A wind turbine has a limited capacity of wind power use, so only a small portion of energy supplied by wind may be converted into usable energy.

15

Przykładowe realizacje pomiarów płaskich pól prędkości wiatru (wersja 2D) w inżynierii wiatrowej

Bosak Grzegorz

Inżynieria i Budownictwo

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2019

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R. 75, nr 3

139--143

PL

Przedstawiono wybrane prace pomiarowe pól prędkości wiatru wykonane za pomocą systemu PIV (Particle Image Velocimetry) w Laboratorium Inżynierii Wiatrowej Politechniki Krakowskiej. Podano zasady pomiaru, scharakteryzowano główne elementy systemu oraz opisano podstawowe zalety i trudności realizacji pomiarów taką techniką. Określono podstawowe obszary badawcze inżynierii wiatrowej, w których pomiary tą techniką mogą mieć praktyczne zastosowania.

EN

The article presents chosen measurement works of wind velocity fields by means of a PIV system (Particle Image Velocimetry) fulfilled in Wind Engineering Laboratory of Cracow University of Technology. The principles of PIV system measurement are presented, the main elements of the system are characterised and fundamental advantages and difficulties of a measurement execution by this type of a technique are described. The basic research fields of wind engineering are defined, in which the measurements of this technique could have practical applications.

16

Assessment of wind energy resources using artificial neural networks – case study at Łódź Hills

Korupczyński R., Trajer J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 1

115--124

EN

The aim of this paper is to answer the question: Are the Łódź Hills useful for electrical energy production from wind energy or not? Due to access to short-term data related to wind measurements (the period of 2008 and 2009) from a local meteorological station, the measure – correlate – predict approach have been applied. Long-term (1979‒2016) reference data were obtained from ECWMF ERA-40 Reanalysis. Artificial neural networks were used to calculate predicted wind speed. The obtained average wind speed and wind power density was 4.21 ms–1 and 70 Wm–1, respectively, at 10 m above ground level (5.51 ms–1, 170 Wm–1 at 50 m). From the point of view of Polish wind conditions, Łódź Hills may be considered useful for wind power engineering.

17

Ekstremalne zjawiska meteorologiczne w Gdyni do 1950 roku

Owczarek M., Miętus M.

Przegląd Geofizyczny

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2018

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Z. 1-2

31--50

PL

W pracy analizowano warunki termiczne, opadowe oraz anemometryczne w Gdyni w latach 1923-1950, które można uznać za ekstremalne. Wyniki z lat 1923-1950 oceniono w odniesieniu do wielolecia referencyjnego 1971-2000 oraz całego okresu pomiarowego 1923-2014. Analizowano rozkłady empiryczne i teoretyczne wybranych elementów meteorologicznych. W przypadku temperatury powietrza wyznaczono wartości kwantyli 5, 10, 90 i 95% rozkładów empirycznych temperatury maksymalnej i minimalnej oraz częstość występowania dni upalnych, fal gorąca i dni bardzo mroźnych. Wyznaczono sumę opadów w ciągu roku podczas dni z opadem o ekstremalnej sumie dobowej, liczbę dni z opadem silnym i bardzo silnym, a także najdłuższe ciągi kolejnych dni z opadem oraz bez opadów. Wyznaczono wartości kwantyli 10 i 90% rozkładu miesięcznych sum opadów. Wyznaczono wartości maksymalnej prędkości wiatru o okresie powtarzalności 5, 10 i 50 lat z zastosowaniem rozkładów GEV (ang. Generalized Extreme Value). Najbardziej znaczące różnice ekstremalnych warunków termicznych pomiędzy rozpatrywanymi wieloleciami stwierdzono w przypadku rocznego rozkładu temperatury minimalnej, który ulega systematycznemu przesunięciu w kierunku wyższych wartości. Wykazano również wzrost najniższych wartości temperatury maksymalnej oraz spadek liczby dni bardzo mroźnych. Różnice ekstremalnych warunków opadowych w poszczególnych wieloleciach mogą świadczyć o zwiększeniu intensywności opadów w niektórych miesiącach półrocza ciepłego oraz wzroście zagrożenia niedoborem opadów w ciągu całego roku. Dodatnie różnice maksymalnej prędkości wiatru, o możliwości wystąpienia co najmniej raz na 50 lat, mogą wskazywać na wzrost ryzyka strat spowodowanych wystąpieniem silnego wiatru.

EN

The aim of the research was to analyze the thermal, precipitation and anemometric conditions in Gdynia in the years 1923-1950, which can be considered as climate extreme. The results of the years 1923-1950 were evaluated for the reference period 1971-2000 and the whole measuring period 1923-2014. The empirical and theoretical frequency distributions of selected meteorological elements were analyzed. Statistical characteristics of the extreme thermal conditions (the values of 5, 10, 90 and 95% quantile of the empirical distributions) as well as the frequency of sweltering days, hot waves and very ice days were determined. Heavy and very heavy precipitation days, the amount of precipitation during days with extreme daily precipitation amount and the longest periods of consecutive days with precipitation and with no precipitation were determined. The maximum wind speed values of 5, 10 and 50-year return period was estimated with the use of Generalized Extreme Values analysis (GEV). The most significant differences in the extreme thermal conditions between the considered periods were found in the annual minimum temperature frequency distribution, which has been shifted towards higher values. It also showed an increase in the lowest values of the maximum temperaturę and a decrease in the number of very cold days. Results related to extreme precipitation conditions may indicate the intensity of precipitation events in some months of the warm season and an increase the risk of meteorological drought over the whole year. The expected return level of the extreme wind speed for 50 year return period, determined in relation to the periods considered, indicates an increase in the risk of losses caused by strong wind.

18

Comparative Analysis of Danger Zone Ranges Determined for LNG in the Coastal Area

Kalbarczyk-Jedynak A., Stochła D., Patsch M.

Multidisciplinary Aspects of Production Engineering

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2018

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Vol. 1, Iss. 1

829--834

EN

The analysis of danger zone ranges for LNG in the coastal area is an important task on account of, inter alia, the safety of human life. It is not an easy process, which is why we consider an danger situation for various weather conditions in the function of constant wind speeds and for various wind speeds in constant weather stability. Pasquill weather stability scale and Beaufort scale with regard to terrain roughness were adopted for the analysis. Both scenarios were considered in the example of Q-flex type vessels in the Świnoujście terminal for two methods of LNG release, i.e. related to a sudden explosion and slow release caused by a leak. The analysis was conducted and considered for the values in the top and bottom flammability limit. Modelling of the danger zone range was analysed with DNV PHAST software, version 7.11. In the process of comparison of the situation related to the risk of explosion in the function of various weather stabilities according to Pasquill scale and constant wind speeds, the values of 1.5 m/s and 5 m/s were adopted, corresponding to 1 and 3 wind force on the Beaufort scale. Those speeds correspond to the water conditions featuring tiny ripples and small waves, the crests of which start to break. The adopted weather stabilities analysed for wind speed equal to 1.5 m/s are A, B, D. A-type stability signifies the least stable atmospheric conditions, and D-type means neutral conditions. In turn, for the wind speed of 5 m/s B, D and F parameters in Pasquill scale were selected. Furthermore, ranges for variable wind speed values were analysed for the selected Pasquill stability.

19

Propozycja skali intensywności wichur, tornad i szkwałów w Polsce

Chmielewski T.

Inżynieria i Budownictwo

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2018

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R. 74, nr 1

35--38

PL

Przedstawiono międzynarodowe skale opisujące intensywność tornad, raport Rządowego Centrum Bezpieczeństwa dotyczący wichur i tornad, częstość występowania tornad i propozycję klasyfikacji maksymalnych prędkości wiatru w Polsce oraz skutków ich działania. Informacje poddano analizie i na podstawie dostępnych danych statystycznych zaproponowano dwie skale klasyfikacji: skalę silnych wiatrów synoptycznych, halnych i fenowych oraz skalę intensywności tornad i szkwałów – oznaczoną jako skala P.

EN

The article presents an overview of international scales, describing the intensity of tornadoes. There is the report from the Government Security Centre on storms and tornadoes, the incidence of tornadoes in Poland, and the proposed classification in 2012 by Lorenc for the maximum wind speed in Poland and effects of their actions. This information was analysed and on the basis of available statistical data two separate intensity scales of strong winds, tornadoes and downbursts in Poland are proposed.

20

An analysis of electricity generation in a wind farm in north-eastern Poland – a case study

Fieducik J.

Ekonomia i Środowisko

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2018

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nr 1

76--95

EN

There are various methods of generating electric power. This article analyzes electricity generation in the Wronki wind farm in Poland. Wind farm specifications and turbine parameters were presented. The correlations between the wind farm’s performance and wind speeds in 2014-2016 were analyzed. Turbine availability was estimated. The economic performance of the wind farm was analyzed by calculating the proceeds from the sale of generated electricity. The wind farm’s environmental impact was determined by calculating the volume of CO2, SO2, NOx, CO and dust emissions associated with the generation of equivalent amounts of electricity in a conventional power plant.