Turbulent Flow in Street Canyons: A Complexity Approach
Velocity measurements and simulations in an idealized urban environment were studied, focusing on turbulent flow over street canyons. Time series of fluctuating velocities were considered as marked point processes, and the distribution of mean residence times was characterized using a lognormal fit....
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MDPI AG
2025-04-01
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| Online Access: | https://www.mdpi.com/1099-4300/27/5/488 |
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| author | Csanád Árpád Hubay Bálint Papp Tamás Kalmár-Nagy |
| author_facet | Csanád Árpád Hubay Bálint Papp Tamás Kalmár-Nagy |
| author_sort | Csanád Árpád Hubay |
| collection | DOAJ |
| description | Velocity measurements and simulations in an idealized urban environment were studied, focusing on turbulent flow over street canyons. Time series of fluctuating velocities were considered as marked point processes, and the distribution of mean residence times was characterized using a lognormal fit. The quadrant method was applied to transform time series into symbolic sequences, enabling the investigation of their information content. By analyzing word frequency and normalized entropy levels, we compared measured and simulated sequences with periodic symbol sequences with and without noise. Our results indicate that noisy periodic sequences exhibit entropy distributions qualitatively similar to those of the measured and simulated data. Surrogate sequences generated using first-, and higher-order Markov statistics also displayed similarity. Higher-order Markov chains provide a more accurate representation of the information content of velocity fluctuation series. These findings contribute to the comparison of experimental and simulation techniques in the investigation of turbulence. |
| format | Article |
| id | doaj-art-ec2fb6efd8f149cf9a2eb42ee51c783e |
| institution | OA Journals |
| issn | 1099-4300 |
| language | English |
| publishDate | 2025-04-01 |
| publisher | MDPI AG |
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| series | Entropy |
| spelling | doaj-art-ec2fb6efd8f149cf9a2eb42ee51c783e2025-08-20T02:33:55ZengMDPI AGEntropy1099-43002025-04-0127548810.3390/e27050488Turbulent Flow in Street Canyons: A Complexity ApproachCsanád Árpád Hubay0Bálint Papp1Tamás Kalmár-Nagy2Department of Fluid Mechanics, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, 1111 Budapest, HungaryDepartment of Fluid Mechanics, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, 1111 Budapest, HungaryDepartment of Fluid Mechanics, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, 1111 Budapest, HungaryVelocity measurements and simulations in an idealized urban environment were studied, focusing on turbulent flow over street canyons. Time series of fluctuating velocities were considered as marked point processes, and the distribution of mean residence times was characterized using a lognormal fit. The quadrant method was applied to transform time series into symbolic sequences, enabling the investigation of their information content. By analyzing word frequency and normalized entropy levels, we compared measured and simulated sequences with periodic symbol sequences with and without noise. Our results indicate that noisy periodic sequences exhibit entropy distributions qualitatively similar to those of the measured and simulated data. Surrogate sequences generated using first-, and higher-order Markov statistics also displayed similarity. Higher-order Markov chains provide a more accurate representation of the information content of velocity fluctuation series. These findings contribute to the comparison of experimental and simulation techniques in the investigation of turbulence.https://www.mdpi.com/1099-4300/27/5/488street canyonturbulencequadrant methodword statisticsentropyMarkov statistics |
| spellingShingle | Csanád Árpád Hubay Bálint Papp Tamás Kalmár-Nagy Turbulent Flow in Street Canyons: A Complexity Approach Entropy street canyon turbulence quadrant method word statistics entropy Markov statistics |
| title | Turbulent Flow in Street Canyons: A Complexity Approach |
| title_full | Turbulent Flow in Street Canyons: A Complexity Approach |
| title_fullStr | Turbulent Flow in Street Canyons: A Complexity Approach |
| title_full_unstemmed | Turbulent Flow in Street Canyons: A Complexity Approach |
| title_short | Turbulent Flow in Street Canyons: A Complexity Approach |
| title_sort | turbulent flow in street canyons a complexity approach |
| topic | street canyon turbulence quadrant method word statistics entropy Markov statistics |
| url | https://www.mdpi.com/1099-4300/27/5/488 |
| work_keys_str_mv | AT csanadarpadhubay turbulentflowinstreetcanyonsacomplexityapproach AT balintpapp turbulentflowinstreetcanyonsacomplexityapproach AT tamaskalmarnagy turbulentflowinstreetcanyonsacomplexityapproach |