TY - JOUR AU - Csemány, Dávid TI - Magas hőmérsékletű nátrium-kén akkumulátor koncentrált paraméterű modellezése JF - ENERGIAGAZDÁLKODÁS J2 - ENERGIAGAZDÁLKODÁS VL - 65 PY - 2024 IS - 1-2 SP - 18 EP - 23 PG - 6 SN - 0021-0757 UR - https://m2.mtmt.hu/api/publication/34816686 ID - 34816686 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Füzesi, Dániel AU - Józsa, Viktor AU - Csemány, Dávid TI - Numerical investigation on the effect of hydrogen share in NH3/H2 blends in a turbulent lean-premixed swirl burner JF - INTERNATIONAL JOURNAL OF HYDROGEN ENERGY J2 - INT J HYDROGEN ENERG VL - 49 PY - 2024 IS - Part B SP - 816 EP - 827 PG - 12 SN - 0360-3199 DO - 10.1016/j.ijhydene.2023.09.091 UR - https://m2.mtmt.hu/api/publication/34193673 ID - 34193673 LA - English DB - MTMT ER - TY - JOUR AU - Jedelský, Jan AU - Malý, Milan AU - Vankeswaram, Sai Krishna AU - Zaremba, Matouš AU - Kardos, Réka AU - Csemány, Dávid AU - Červenec, Adam AU - Józsa, Viktor TI - Effects of secondary breakup, collision dynamics, gravity and evaporation on droplet size distribution in a pressure-swirl JET A-1 spray JF - FUEL J2 - FUEL VL - 359 PY - 2024 PG - 21 SN - 0016-2361 DO - 10.1016/j.fuel.2023.130103 UR - https://m2.mtmt.hu/api/publication/34450307 ID - 34450307 N1 - Funding Agency and Grant Number: Czech Science Foundation [GA 22- 17806S, BO/00119/22/6]; National Research, Development and Innovation Fund of Hungary [OTKA-FK 137758]; Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences [BO/00119/22/6] Funding text: The authors acknowledge financial support from project No. GA 22- 17806S funded by Czech Science Foundation. The support of the Hungarian researchers acknowledge the National Research, Development and Innovation Fund of Hungary, project No. OTKA-FK 137758 and the Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences, No. BO/00119/22/6. Jan Jedelsky thanks to students participating on the topic within Unigo Scholarship Program: Leonardo Nascimento Parmigiani (University of Campinas, Brasil); Joao Pedro de Toni de Almeida (Universidade Federal de Santa Catarina, Florianopolis, Brasil), Ronant de Paula Monteiro (Sao Jose dos Campos College of Technology, Sao Paulo, Brasil), and Felipe Fideles de Camara (Sao Carlos School of Engineering, University of Sao Paulo, Brasil) . AB - Size and velocity of droplets in pressure-swirl sprays vary with distance downstream the nozzle. This study aims to explain the phenomena contributing to size-resolved spatial variation of the drop size distribution for Jet A-1 spray from a small pressure swirl atomizer injected into quiescent ambient air at atmospheric conditions. The effects of secondary breakup, droplet collisions, gravity, drag-driven spray dispersion, and evaporation are evaluated. Phase Doppler anemometer (PDA) was used to resolve the velocity and size of the droplets in radial profiles at several axial distances (Z) from the nozzle exit at injection pressures between 0.5 and 1.5 MPa. The droplet motion and collision dynamics were qualitatively characterised by high-speed imaging. The analysis focused on areas along 1) the spray axis and 2) the liquid sheet direction. The first area covers small droplets with marginal evolution, while the mean drop size in the second area significantly increases downstream. The local drop size distribution and its axial evolution results from a combined effect of ballistic filtering (drifting of small droplets from periphery to spray centre and large droplets vice versa), centrifugal and turbulent droplet dispersion, and droplet collisions (increasing drop size with distance). The relative droplet-gas velocity was found at investigated Z positions too small for drag-driven secondary droplet breakup to occur. Evaporation of Jet A-1 sprayed at room temperature and pressure into still atmosphere reduces the drop size marginally. Trajectory of all drop sizes is insignificantly altered by gravity. The smallest droplets are strongly drag-driven to the spray axis, while large ones disperse centrifugally and have sufficient momentum to neglect the gravity. Combining results from imaging and laser diagnostics, various collision outcomes were identified, with a conclusion that these depend on the size and velocity of colliding droplets. Coalescing collisions dominate and strongly increase the mean drop size downstream the spray at off-axis positions while insignificantly contribute along the spray axis. The drop size span factor reduces with Z as separative collisions between large droplets and mixed-type collisions between small and large droplets narrow the drop size distribution. The above effects can be most easily amplified for drop size reduction via modification of physical properties of sprayed liquid by its heating. LA - English DB - MTMT ER - TY - JOUR AU - Csemány, Dávid TI - Thermal analysis of suspended single droplet evaporation measurements with a coupled lumped parameter model JF - HEAT AND MASS TRANSFER J2 - HEAT MASS TRANSFER VL - 59 PY - 2023 SP - 2181 EP - 2195 PG - 15 SN - 0947-7411 DO - 10.1007/s00231-023-03403-6 UR - https://m2.mtmt.hu/api/publication/34068145 ID - 34068145 N1 - Correspondence Address: Csemány, D.; Department of Energy Engineering, Műegyetem Rkp. 3., Hungary; email: csemany@energia.bme.hu AB - The measurement data of single droplet evaporation experiments are often biased due to the extra heat input through the fiber suspension and the presence of thermal radiation in hot environments. This encumbers model validation for heat and mass transfer simulations of liquid droplets. In this paper, a thermal analysis of this measurement layout is presented with a coupled lumped parameter model, considering heat conduction through the suspension. The model was validated by experimental data from the literature and good agreements were found. The thermal analysis focused on fiber material and geometry, and thermal radiation properties. Calculations were performed on a broad range of ambient conditions for liquids with different volatility characteristics. Temporal squared droplet diameter- and temperature-profiles, furthermore, droplet stationary evaporation rate were used to characterize vaporization phenomena. The thermal balance of the droplet is dominated by the convective heat rate from the environment in the early stage of evaporation. The effect of heat conduction through the fiber becomes important at the end of the droplet lifetime when the droplet size is decreased. Temperature sensor suspension may seriously bias droplet temperature due to the larger thermal conductivity compared to quartz fiber. Large droplets in high-temperature environments show significant sensitivity to thermal radiation properties, which should be considered in measurements and model validation. LA - English DB - MTMT ER - TY - CONF AU - Csemány, Dávid AU - Hirják, Árpád Botond AU - Nagy, Attila AU - Guba, Attila AU - Józsa, Viktor TI - PIV measurement of distributed combustion without air dilution T2 - Proceedings of the 11th European Combustion Meeting PY - 2023 SP - 75 EP - 80 PG - 6 UR - https://m2.mtmt.hu/api/publication/34029466 ID - 34029466 LA - English DB - MTMT ER - TY - THES AU - Csemány, Dávid TI - Modeling and experimental aspects of renewable liquid fuel vaporization PB - Budapesti Műszaki és Gazdaságtudományi Egyetem PY - 2023 SP - 173 UR - https://m2.mtmt.hu/api/publication/33645142 ID - 33645142 LA - English DB - MTMT ER - TY - CONF AU - Füzesi, Dániel AU - Trindade, Marcelo AU - Csemány, Dávid AU - Nagy, Attila AU - Guba, Attila AU - Józsa, Viktor TI - Numerical simulation of NH3/H2 blends in an experimental swirl burner T2 - Proceedings of the 11th European Combustion Meeting PY - 2023 SP - 2431 EP - 2436 PG - 6 UR - https://m2.mtmt.hu/api/publication/34029567 ID - 34029567 LA - English DB - MTMT ER - TY - CONF AU - Kardos, Réka AU - Rácz, Erika AU - Csemány, Dávid AU - Maly, Milan AU - Jedelsky, Jan AU - Józsa, Viktor TI - Measurement and evaporation modeling of JP-8, diesel, and biodiesel sprays under hot conditions T2 - Proceedings of the 11th European Combustion Meeting PY - 2023 SP - 1586 EP - 1591 PG - 6 UR - https://m2.mtmt.hu/api/publication/34029532 ID - 34029532 LA - English DB - MTMT ER - TY - JOUR AU - Tóthpálné Hidegh, Gyöngyvér AU - Csemány, Dávid AU - DarAli, Osama Naser Mohammad AU - Rizvi, Syed Ali Hamza AU - Ng, Jo-Han AU - Chong, Cheng Tung AU - Józsa, Viktor TI - Comparison of thermophysical properties and combustion characteristics of various biodiesels in a non-MILD ultra-low emission swirl burner JF - FUEL J2 - FUEL VL - 334 PY - 2023 IS - 1 PG - 15 SN - 0016-2361 DO - 10.1016/j.fuel.2022.126583 UR - https://m2.mtmt.hu/api/publication/33226117 ID - 33226117 N1 - Budapest University of Technology and Economics, Faculty of Mechanical Engineering, Department of Energy Engineering, 1111 Budapest, Műegyetem rkp. 3., Hungary Faculty of Engineering and Physical Sciences, University of Southampton Malaysia (UoSM), Johor, Iskandar Puteri, 79100, Malaysia China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai, Lingang, 201306, China Correspondence Address: Csemány, D.; Budapest University of Technology and Economics, 1111 Budapest, Műegyetem rkp. 3., Hungary; email: csemany@energia.bme.hu LA - English DB - MTMT ER - TY - JOUR AU - Csemány, Dávid AU - DarAli, Osama Naser Mohammad AU - Rizvi, Syed Ali Hamza AU - Józsa, Viktor TI - Comparison of volatility characteristics and temperature-dependent density, surface tension, and kinematic viscosity of n-butanol-diesel and ABE-diesel fuel blends JF - FUEL J2 - FUEL VL - 312 PY - 2022 PG - 13 SN - 0016-2361 DO - 10.1016/j.fuel.2021.122909 UR - https://m2.mtmt.hu/api/publication/32547306 ID - 32547306 N1 - Funding Agency and Grant Number: National Research Development and Innovation Fund (TKP2020 National Challenges Subprogram) under Ministry for Innovation and Technology [BME-NCS]; Ministry for Innovation and Technology [OTKA-FK 124704, 137758, 134277]; New National Excellence Program of the Ministry for Innovation and Technology [UNKP-20-3-II-BME-178] Funding text: The research reported in this paper and carried out at the Budapest University of Technology and Economics has been supported by the National Research Development and Innovation Fund (TKP2020 National Challenges Subprogram, Grant No. BME-NCS) based on the charter of bolster issued by the National Research Development and Innovation Office under the auspices of the Ministry for Innovation and Technology and project N degrees.s OTKA-FK 124704, 137758, and 134277 and the New National Excellence Program of the Ministry for Innovation and Technology project N degrees. UNKP-20-3-II-BME-178. LA - English DB - MTMT ER -