TY - JOUR AU - Papp, Bálint AU - Istók, Balázs AU - Koren, Márton AU - Balczó, Márton AU - Kristóf, Gergely TI - Statistical assessment of the concentration fluctuations in street canyons via time-resolved wind tunnel experiments JF - JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS J2 - J WIND ENG IND AEROD VL - 246 PY - 2024 PG - 17 SN - 0167-6105 DO - 10.1016/j.jweia.2024.105665 UR - https://m2.mtmt.hu/api/publication/34742505 ID - 34742505 N1 - Export Date: 18 March 2024 Correspondence Address: Papp, B.; Department of Fluid Mechanics, Műegyetem rkp. 3, Hungary; email: papp.balint@gpk.bme.hu Funding details: European Commission, EC, VEKOP-2.3.3-15-2017-00017 Funding details: Gedeon Richter, PD 127919 Funding details: Richter Gedeon Talentum Alapítvány Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA Funding details: Innovációs és Technológiai Minisztérium, ÚNKP-21-3-I-BME-252 Funding details: National Research, Development and Innovation Office, TKP-6-6 Funding text 1: The present study was funded by grant no. K 124439 from the National Research, Development, and Innovation Office, Hungary. Project no. TKP-6-6/PALY-2021 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-NVA funding scheme. Bálint Papp's contribution to this paper was supported by the ÚNKP-21-3 New National Excellence Program of the Ministry for Innovation and Technology (Grant No. ÚNKP-21-3-I-BME-252), as well as by the Gedeon Richter Talent Foundation (registered office: Gyömrői út 19–21, 1103 Budapest, Hungary), established by Gedeon Richter Plc. within the framework of the Gedeon Richter PhD Scholarship. Márton Balczó gratefully acknowledges the support of project PD 127919 of the National Research, Development, and Innovation (NRDI) Fund, entitled “Application and validation of measurement techniques related to the physical modeling of the atmospheric boundary layer in a new boundary layer wind tunnel”. The authors wish to acknowledge the support of the European Union and of the Hungarian Government in the project VEKOP-2.3.3-15-2017-00017 "Establishment of a Laboratory for Atmospheric Flows". Funding text 2: The present study was funded by grant no. K 124439 from the National Research, Development, and Innovation Office, Hungary . Project no. TKP-6-6/PALY-202 1 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-NVA funding scheme. Bálint Papp's contribution to this paper was supported by the ÚNKP-21-3 New National Excellence Program of the Ministry for Innovation and Technology (Grant No. ÚNKP-21-3-I-BME-252 ), as well as by the Gedeon Richter Talent Foundation (registered office: Gyömrői út 19–21, 1103 Budapest, Hungary), established by Gedeon Richter Plc., within the framework of the Gedeon Richter PhD Scholarship. Márton Balczó gratefully acknowledges the support of project PD 127919 of the National Research, Development, and Innovation (NRDI) Fund , entitled “Application and validation of measurement techniques related to the physical modeling of the atmospheric boundary layer in a new boundary layer wind tunnel”. The authors wish to acknowledge the support of the European Union and of the Hungarian Government in the project VEKOP-2.3.3-15-2017-00017 "Establishment of a Laboratory for Atmospheric Flows". AB - Time-resolved wind tunnel experiments are performed for three periodic street canyon configurations: one of uniform (H/W = 1) and two of variable building height (consisting of 0.5H and 1.5H tall towers in aligned and staggered arrangements) for perpendicular wind direction. The velocity field is mapped using Laser Doppler Anemometry (LDA), and the tracer gas concentration is sampled using Fast Flame Ionization Detection (FFID). The concentration field is characterized by the mean concentration and the characteristic percentiles of the concentration-time series, such as the median and the peak, represented by the 99th percentile, in a total of 1138 sampling points. The probability distribution of the concentration in each point is modeled using the gamma distribution, which is fitted based on the mean and the variance of the measured time series. The results show that the mean pedestrian exposure to air pollutants is significantly lower in the case of heterogeneous roof height, although the mean concentration at the leeward corner of the source canyon can locally exceed those of the uniform street canyons for both tower arrangements of variable building height. Moreover, it is shown that the concentration peaks for both tower configurations can significantly exceed those of the uniform canyons case, especially near the sources. © 2024 The Authors LA - English DB - MTMT ER - TY - CHAP AU - Papp, Bálint AU - Istók, Balázs AU - Koren, Márton AU - Balczó, Márton AU - Kristóf, Gergely ED - Jurčáková, Klára ED - Kellnerová, Radka TI - Statistical assessment of the ventilation of street canyons based on time-resolved wind tunnel experiments T2 - PHYSMOD 2022 - International Workshop on Physical Modeling of Flow and Dispersion Phenomena PB - Ústav termomechaniky AV ČR CY - Prága SN - 9788087012819 PY - 2022 SP - 143 EP - 155 PG - 12 UR - https://m2.mtmt.hu/api/publication/33113557 ID - 33113557 LA - English DB - MTMT ER - TY - JOUR AU - He, Haijun AU - Guo, Jian AU - Illés, Balázs György AU - Géczy, Attila AU - Istók, Balázs AU - Hliva, Viktor AU - Török, Dániel AU - Kovács, József Gábor AU - Harmati, István AU - Molnár, Kolos TI - Monitoring Multi-respiratory Indices via a Smart Nanofibrous Mask Filter Based on a Triboelectric Nanogenerator JF - NANO ENERGY J2 - NANO ENERGY VL - 89 PY - 2021 IS - B PG - 12 SN - 2211-2855 DO - 10.1016/j.nanoen.2021.106418 UR - https://m2.mtmt.hu/api/publication/32132140 ID - 32132140 N1 - Department of Polymer Engineering, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3, Budapest, H-1111, Hungary Department of Control Engineering and Information Technology, Faculty of Electrical Engineering and Informatics, Budapest University of Technology and Economics, Műegyetem rkp. 3, Budapest, H-1111, Hungary Department of Electronics Technology, Faculty of Electrical Engineering and Informatics, Budapest University of Technology and Economics, Műegyetem rkp. 3, Budapest, H-1111, Hungary Department of Fluid Mechanics, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3, Budapest, H-1111, Hungary MTA–BME Research Group for Composite Science and Technology, Műegyetem rkp. 3, Budapest, H-1111, Hungary MTA-BME Lendület Lightweight Polymer Composites Research Group, Műegyetem rkp. 3, Budapest, H-1111, Hungary Cited By :2 Export Date: 10 May 2022 Correspondence Address: Molnár, K.; Department of Polymer Engineering, Műegyetem rkp. 3, Hungary; email: molnar@pt.bme.hu LA - English DB - MTMT ER - TY - JOUR AU - Papp, Bálint AU - Kristóf, Gergely AU - Istók, Balázs AU - Koren, Márton AU - Balczó, Márton AU - Balogh, Miklós TI - Measurement-driven Large Eddy Simulation of dispersion in street canyons of variable building height JF - JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS J2 - J WIND ENG IND AEROD VL - 211 PY - 2021 PG - 16 SN - 0167-6105 DO - 10.1016/j.jweia.2020.104495 UR - https://m2.mtmt.hu/api/publication/31806292 ID - 31806292 LA - English DB - MTMT ER - TY - CHAP AU - Istók, Balázs ED - Bíró, Tibor TI - Lézerscannelt 3D felszínmodell alkalmazása csatornakiöntések modelljének pontosítására T2 - Országos Települési Csapadékvíz-gazdálkodási Konferencia tanulmányai PB - Dialóg Campus Kiadó CY - Budapest SN - 9786155845222 PY - 2019 SP - 180 EP - 189 PG - 10 UR - https://m2.mtmt.hu/api/publication/3423019 ID - 3423019 AB - Extrém csapadékvíz terhelés az egyesített rendszerű vagy a csapadékvíz elvezető hálózat túlterhelődéséhez vezethet, az elvezetendő víz a hálózatból kilépve, fedlapokon, árkok peremén átbukva, a környező utcákra, területekre folyhat. A kiöntés modellezése segít megérteni a jelenség folyamatát, rámutat a probléma okára és lehetőséget nyújt megelőző intézkedések várható hatásának a számításában. Hagyományos csatornahidraulikai modellek alkalmazása esetén az elvezető hálózatból kilépő víz egy virtuális tárolóba kerül, amelynek kapacitása a modell paramétere, jellemzően a környező területek méretéből határozható meg. A kiáramlás akadálytalanul történik meg, a virtuális tárolóban a túlterhelést okozó víz tározódik és az árhullám elvonulását követően a kiöntés helyén visszafolyik az elvezető hálózatba. A hálózaton kívüli, felszíni vízmozgás pontos meghatározása a legtöbb modellező szoftverben nem megoldott vagy korlátozott mértékben elérhető. Jelen dolgozat célja, hogy egy szintetikus és egy valós csatornahálózat modelljével végzett számításon keresztól bemutassa a felszíni vízmozgás modellezésének új lehetőségeit a felszíni vízáramlás és az elöntési képek pontos meghatározásával. A számítások és a modellezés egy repülőgéppel végzett terepszkennelés alapján felépített, nagy felbontású terepmodell-lel történik. Hagyományos dinamikus csatornahidraulikai modellezéssel meghatározásra került a vízmozgás a csatornahálózatban. Ez alapján a felszínmodell-lel megjeleníthetővé válik a kiöntés folyamata, az elárasztott terület, a felszíni vízmozgás és a csatornahálózatba történő visszaáramlás. LA - Hungarian DB - MTMT ER - TY - THES AU - Istók, Balázs TI - Egyesített rendszerű csatornahálózatok környezeti kibocsátásainak elemzése PB - Budapesti Műszaki Egyetem, Áramlástan Tanszék PY - 2014 SP - 114 UR - https://m2.mtmt.hu/api/publication/2856292 ID - 2856292 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Istók, Balázs AU - Kristóf, Gergely TI - Dispersion and travel time of dissolved and floating tracers in urban sewers JF - SLOVAK JOURNAL OF CIVIL ENGINEERING J2 - SLOVAK J CIV ENG VL - 22 PY - 2014 IS - 1 SP - 1 EP - 8 PG - 8 SN - 1210-3896 DO - 10.2478/sjce-2014-0001 UR - https://m2.mtmt.hu/api/publication/2696094 ID - 2696094 AB - Environmental impacts of oil spills affecting urban sewage networks can be eliminated if timely intervention is taken. Design of such actions requires the knowledge of transport of surface pollutants in open channels. In this study we investigated travel time and dispersion by means of tracer experiments in sewage networks and in a creek. Travel time of surface tracers has been found to be significantly shorter than that of the bulk flow tracer. The ratio of travel times of bulk flow tracer and surface tracers agreed with known correlations obtained for rivers. An increasing tendency of the ratio of travel times has been observed for increasing bulk flow velocity. A segment-wise dispersion model was implemented in the existing hydraulic model of the sewer system. Simulation results were compared with experimental observations. Dispersion rate of the bulk flow tracer has been found to obey Taylor’s mixing theory for long channels and was more intensive than that of surface tracers in community sewage channels. LA - English DB - MTMT ER - TY - JOUR AU - Istók, Balázs AU - Kristóf, Gergely TI - Rain model for investigating overflow in combined sewer systems under regular operating conditions JF - INTERNATIONAL JOURNAL OF ADVANCES IN ENGINEERING SCIENCE AND TECHNOLOGY J2 - IJAEST VL - 6 PY - 2013 IS - 5 SP - 1967 EP - 1976 PG - 10 SN - 2231-1963 DO - 10.7323/ijaet UR - https://m2.mtmt.hu/api/publication/2695655 ID - 2695655 AB - In combined sewer systems, even regularly occurring heavy rainfall can cause overflows to occur under regular operating conditions. These overflows result in a mixture of rainfall and raw wastewater being transported to the receiving water body. Though hydraulic models provide a means for calculating the amount of overflow resulting from a given rain event, correct estimations for the annual amount of pollution can only be made after processing multiple year’s worth of rain event data. In order to reduce the time needed to complete the numerical simulations, a method is proposed for correctly modeling the overflow of a long series of historical rainfall data, using a reduced input dataset. Based on rainfall intensity measurements, a series of rain events was divided into block rains. The complete series of block rains was then replaced with 9 representative (weighted) block rains, each of equal rainfall. The method was tested on the hydraulic model of a 7500 ha catchment of the Budapest combined sewer system. When compared to overflow results attained by processing 3 years worth of rainfall data, sampled in 10 minute intervals, the overflow results of the 9 element numerical model deviated by less than 12%. The time necessary to complete the hydraulic simulations of the latter was 1/27th of the former. These faster numerical models will enable designers to search for optimal technological solutions from both an environmental as well as economic point of view. LA - English DB - MTMT ER - TY - JOUR AU - Istók, Balázs AU - Kristóf, Gergely TI - Method for identification of the initial loss of combined sewer catchments JF - PERIODICA POLYTECHNICA-CIVIL ENGINEERING J2 - PERIOD POLYTECH CIV ENG VL - 57 PY - 2013 IS - 2 SP - 185 EP - 190 PG - 6 SN - 0553-6626 DO - 10.3311/PPci.7173 UR - https://m2.mtmt.hu/api/publication/2693354 ID - 2693354 AB - Intense, short periods of rainfall cause the greatest number of operational overflows, leading to the discharge of untreated sewage in combined sewerage systems of large cities. The annual amount of pollution can be estimated based on meteorological, orographic, surface coverage and hydraulic information, by using a detailed hydraulic model of the sewerage system. The most widely used hydrological models require input for the initial loss in order to define the amount of water remaining in the catchment, which decreases the load of the sewer and potentially, the amount of overflow. Earlier measurements of the initial loss were made only in rainwater channels. The results range from 0-6 mm in urban territory, which makes the case-by-case identification of this model parameter very important. A methodology is presented in this paper for calculating the amount of initial loss in a combined system catchment without any on-site measurements. The initial loss was identified for a 4500 ha catchment of Budapest. In addition, the dependence of the initial loss on the environmental temperature was analysed. LA - English DB - MTMT ER - TY - CONF AU - Istók, Balázs TI - Egyesített rendszer környezeti hatásainak elemzése. Környezeti kihívások - Hazai megoldások TS - Környezeti kihívások - Hazai megoldások T2 - VII. Szennyvízágazati Konferencia PY - 2010 UR - https://m2.mtmt.hu/api/publication/2691148 ID - 2691148 LA - Hungarian DB - MTMT ER -