Object's details: Selected Spectral Characteristics of Turbulence over an Urbanized Area in the Centre of Łódź, Poland

Provider:Repozytorium Uniwersytetu Łódzkiego

Description

Title:
Selected Spectral Characteristics of Turbulence over an Urbanized Area in the Centre of Łódź, Poland
Creator:
Fortuniak, Krzysztof;
Pawlak, Włodzimierz
Contributor:
University of Łódź, Department of Meteorology and Climatology, Faculty of Geographical Sciences;
kfortun@uni.lodz.pl
Description:
We present the turbulence spectra and cospectra derived frommore than five years of eddy-covariance measurements at two urban sites inŁód´z, central Poland. The fast response wind velocity components were obtained using sonic anemometers placed on narrow masts at 37 and 42 m above ground level. The analysis follows Kaimal et al. (Q J R Meteorol Soc 98:563–589, 1972) who established the spectral and cospectral properties of turbulent flow in atmospheric surface layer on the basis of the Kansas experiment. Our results illustrate many features similar to those of Kaimal et al., but some differences are also observed. The velocity (co)spectra from Łód´z show a clear inertial subrange with −2/3 slope for spectra and −4/3 slope for cospectra. We found that an appropriate stability function for the non-dimensional dissipation of turbulent kinetic energy calculated from spectra in the inertial subrange differs from that of Kaimal et al., and it can be satisfactorily estimated with the assumption of local equilibrium using standard functions for the non-dimensional shear production. A similar function for the cospectrum corresponds well to Kaimal et al. for unstable and weakly stable conditions. The (co)spectra normalized by their spectral values in the inertial subrange are in general similar to those of Kaimal et al., but they peak at lower frequencies in strongly stable conditions. Moreover, our results do not confirm the existence of a clear “excluded region” at low frequencies for the transition from stable to unstable conditions, for longitudinal and lateral wind components. The empirical models of Kaimal et al. with adjusted parameters fit well to the vertical velocity spectrum and the vertical momentum flux cospectrum. The same type of function should be used for longitudinal and lateral wind spectra because of their sharper peak than occurs for the Kansas data. Finally, it should be stressed that the above relationships are well-defined for averaged values. The results for individual 1-h periods are very scattered and can be significantly different from the generalized functions.;
Funding for this research was provided by the Polish Ministry of Science and Higher Education (State Committee for Scientific Research) under grant no. N306 276935 for the years 2008–2012 and grant no. N306 519638 for the years 2010–2013.
Object availability:
free access
Rights:
Uznanie autorstwa 3.0 Polska;
http://creativecommons.org/licenses/by/3.0/pl
Date:
2015.06.18;
2014.08.29
Type:
Article
Language:
English;
eng
Format:
application/pdf
Publisher:
Springer Science+Business Media
Relation:
Boundary-Layer Meteorology;(2015) 154
Subject:
Dissipation of turbulent kinetic energy;
Eddy-covariance method;
Turbulence spectra;
Universal functions;
Urban climate
Identifier:
1573-1472;
http://hdl.handle.net/11089/9947
Dostawca danych:
Repozytorium Uniwersytetu Łódzkiego

Similar objects

Selected Spectral Characteristics of Turbulence over an Urbanized Area in the Centre of Łódź, Poland

Creator:Fortuniak, Krzysztof | Pawlak, Włodzimierz

Date:2015.06.18 | 2014.08.29

Type:image

Zastosowanie aplikacji EddyPro® (LI-COR, USA) do obliczania turbulencyjnych strumieni masy i energii z zastosowaniem metody kowariancji wirów (na przykładzie pomiarów w Kopytkowie na terenie Biebrzańskiego Parku Narodowego)

Creator:Pawlak, Włodzimierz | Fortuniak, Krzysztof

Date:2017.01.16 | 2016

Type:text

Metody weryfikacji jakości danych i określania obszaru źródłowego strumieni turbulencyjnych

Creator:Fortuniak, Krzysztof | Pawlak, Włodzimierz

Date:2017.01.12 | 2016

Type:text

Sustainable development of urban spaces towards climate protection and adaptation to its changes

Creator:Wojtyszyn, Bogusław J.

Date:2020

Type:image

Spatiotemporal variation of terrestrial carbon sequestration in tropical urban area (case study in Surakarta District, Indonesia)

Creator:Danardono, Danardono | Sunariya, M. Iqbal Taufiqurrahman | Fikriyah, Vidya Nahdiyatul | Cholil, Munawar

Date:2021.09.01

Type:other

Urban Nature as an Active Means of Adapting Public Spaces to Climate Conditions: Case Studies from Copenhagen and Selected Polish Cities

Creator:Pancewicz, Alina

Date:2022

Type:image

River Park Assessment: 2D Hydraulic Watercourse Modeling for Nature-based Solutions in Urban Area

Creator:Halecki, Wiktor | Bedla, Dawid | Plesiński, Karol | Ziernicka-Wojtaszek, Agnieszka

Date:2023

Type:image

Climate as an area of strategic intervention in urban development

Creator:Plac, Klaudia

Date:2020.12.31 | 2020

Type:image

Federacja Bibliotek Cyfrowych

Object's details: Selected Spectral Characteristics of Turbulence over an Urbanized Area in the Centre of Łódź, Poland

Description

Similar objects