@article{MTMT:3121318,
	title = {Implementation and validation of a bulk microphysical model of moisture transport in a pressure based CFD solver},
	url = {https://m2.mtmt.hu/api/publication/3121318},
	author = {Rácz, Norbert and Kristóf, Gergely},
	journal-iso = {IDŐJÁRÁS},
	journal = {IDŐJÁRÁS / QUARTERLY JOURNAL OF THE HUNGARIAN METEOROLOGICAL SERVICE},
	volume = {120},
	unique-id = {3121318},
	issn = {0324-6329},
	abstract = {We study wet cooling tower plume formation involving mesoscale meteorological effects (such as stratification or compressibility). This was achieved by incorporating transformations and volume source terms into a pressure based computational fluid dynamics (CFD) solver (ANSYS-FLUENT). Moisture dynamics is taken into account with a bulk microphysical model that was recently implemented into the solver. This model has been validated against known numerical solutions of idealized two-dimensional dry and wet thermals. In particular, the overall thermal profile and the liquid water concentration field indicated good model performance. Model performance has also been compared with measurements for the formation of a large wet cooling tower plume. Simulations are encouraging with regard to the predictability of cumulus like plume structures with complex thermal stratification, the overall liquid water content along the plume axis, and also the turbulent fluctuations caused by the vertical movements in the plume. The advantage of this approach is that a uniform physical description can be used for close- and far-field flow by using a single unstructured mesh with local refinements. This allows for investigating the finely structured microscale flow phenomena around complex orographic features in a single framework.},
	keywords = {simulation; dispersion; RISE; Phase Change; entrainment; TURBULENT FLOWS; CHIMNEY PLUMES; CUMULUS CLOUDS; DROPLET SPECTRUM; CLOUD-ENVIRONMENT INTERFACE; COOLING-TOWER PLUME; wet cooling tower plume; rising thermal; wet adiabatic processes; humidity transport},
	year = {2016},
	eissn = {0324-6329},
	pages = {231-254},
	orcid-numbers = {Kristóf, Gergely/0000-0001-7572-6875}
}

@mastersthesis{MTMT:3249338,
	title = {Micro- and mesoscale modeling of thermal convection, internal waves and cloud formation in the atmosphere (Mikro- és mezoskálájú áramlások, termikus konvekció, gravitációs hullámok és felhőképződés mo},
	url = {https://m2.mtmt.hu/api/publication/3249338},
	author = {Rácz, Norbert},
	publisher = {Budapest University of Technology and Economics},
	unique-id = {3249338},
	year = {2015}
}

@article{MTMT:2695298,
	title = {Evaluation and validation of a CFD solver adapted to atmospheric flows: Simulation of topography-induced waves},
	url = {https://m2.mtmt.hu/api/publication/2695298},
	author = {Rácz, Norbert and Kristóf, Gergely and Weidinger, Tamás},
	journal-iso = {IDŐJÁRÁS},
	journal = {IDŐJÁRÁS / QUARTERLY JOURNAL OF THE HUNGARIAN METEOROLOGICAL SERVICE},
	volume = {117},
	unique-id = {2695298},
	issn = {0324-6329},
	abstract = {Mountain wave phenomena have been simulated by using a well-known general purpose computational fluid dynamic (CFD) simulation system adapted to atmospheric flow modeling. Mesoscale effects have been taken into account with a novel approach based on a system of transformations and customized volume sources acting in the conservation and governing equations. Simulations of linear hydrostatic wave fields generated by a two-dimensional obstacle were carried out, and the resulting vertical velocity fields were compared against the corresponding analytic solution. Validation with laboratory experiments and full-scale atmospheric flows is a very important step toward the practical application of the method. Performance measures showed good correspondence with measured data concerning flow structures and wave pattern characteristics of non-hydrostatic and nonlinear mountain waves in low Reynolds number flows. For highly nonlinear atmospheric scale conditions, we reproduced the well-documented downslope windstorm at Boulder in January 1972, during which extreme weather conditions, with a wind speed of approximately 60 m s–1, were measured close to the ground. The existence of the hydraulic jump, the strong descent of the stratospheric air, wave breaking regions, and the highly accelerated downslope wind were well reproduced by the model. Evaluation based on normalized mean square error (NMSE), fractional bias (FB), and predictions within a factor of two of observations (FAC2) show good model performance, however, due to the horizontal shift in the flow pattern, a less satisfactory hit rate and correlation value can be observed.},
	keywords = {BOUNDARY-LAYER; COMPLEX TERRAIN; model validation; Numerical simulations; Splitting methods; gravity waves; CFD SIMULATION; URBAN HEAT-ISLAND; k-epsilon model; TURBULENCE CLOSURE-MODEL; TIME INTEGRATION METHODS; VERTICAL DIFFUSION; EDDY VISCOSITY},
	year = {2013},
	eissn = {0324-6329},
	pages = {239-275},
	orcid-numbers = {Kristóf, Gergely/0000-0001-7572-6875; Weidinger, Tamás/0000-0001-7500-6579}
}

@article{MTMT:2644657,
	title = {Adaptation of Pressure Based CFD Solvers for Mesoscale Atmospheric Problems},
	url = {https://m2.mtmt.hu/api/publication/2644657},
	author = {Kristóf, Gergely and Rácz, Norbert and Balogh, Miklós},
	doi = {10.1007/s10546-008-9325-7},
	journal-iso = {BOUND-LAY METEOROL},
	journal = {BOUNDARY-LAYER METEOROLOGY},
	volume = {131},
	unique-id = {2644657},
	issn = {0006-8314},
	abstract = {General purpose Computational Fluid Dynamics (CFD) solvers are frequently used in small-scale urban pollution dispersion simulations without a large extent of ver- tical flow. Vertical flow, however, plays an important role in the formation of local breezes, such as urban heat island induced breezes that have great significance in the ventilation of large cities. The effects of atmospheric stratification, anelasticity and Coriolis force must be taken into account in such simulations. We introduce a general method for adapting pressure based CFD solvers to atmospheric flow simulations in order to take advantage of their high flexibility in geometrical modelling and meshing. Compressibility and thermal stratification effects are taken into account by utilizing a novel system of transformations of the field variables and by adding consequential source terms to the model equations of incompressible flow. Phenomena involving mesoscale to microscale coupled effects can be analyzed without model nesting, applying only local grid refinement of an arbitrary level. Elements of the method are validated against an analytical solution, results of a reference calculation, and a laboratory scale urban heat island circulation experiment. The new approach can be applied with benefits to several areas of application. Inclusion of the moisture transport phenomena and the surface energy balance are important further steps towards the practical application of the method.},
	keywords = {MODEL; TRANSFORMATION; CONVECTION; Computational fluid dynamics; URBAN HEAT-ISLAND; Dispersion of pollutants; Mesoscale flows},
	year = {2009},
	eissn = {1573-1472},
	pages = {85-103},
	orcid-numbers = {Kristóf, Gergely/0000-0001-7572-6875}
}

@article{MTMT:2687305,
	title = {Atmoszférikus áramlások szimulációja},
	url = {https://m2.mtmt.hu/api/publication/2687305},
	author = {Kristóf, Gergely and Rácz, Norbert and Balogh, Miklós},
	journal-iso = {GÉP},
	journal = {GÉP},
	volume = {59},
	unique-id = {2687305},
	issn = {0016-8572},
	year = {2008},
	pages = {24-25},
	orcid-numbers = {Kristóf, Gergely/0000-0001-7572-6875}
}

@CONFERENCE{MTMT:2645966,
	title = {Application of ANSYS-FLUENT for Meso-Scale Atmospheric Flow Simulations},
	url = {https://m2.mtmt.hu/api/publication/2645966},
	author = {Kristóf, Gergely and Rácz, Norbert and Balogh, Miklós},
	booktitle = {ANSYS Conference & 25. CADFEM Users’ Meeting},
	unique-id = {2645966},
	year = {2007},
	orcid-numbers = {Kristóf, Gergely/0000-0001-7572-6875}
}

@CONFERENCE{MTMT:2644665,
	title = {CFD analyses of flow in stratified atmosphere},
	url = {https://m2.mtmt.hu/api/publication/2644665},
	author = {Kristóf, Gergely and Rácz, Norbert and Balogh, Miklós},
	booktitle = {Proceedings of International Workshop on Physical Modelling of Flow and Dispersion Phenomena},
	unique-id = {2644665},
	year = {2007},
	pages = {93-97},
	orcid-numbers = {Kristóf, Gergely/0000-0001-7572-6875}
}

@CONFERENCE{MTMT:2644663,
	title = {Simulation of gravity waves and model validation to laboratory experiments},
	url = {https://m2.mtmt.hu/api/publication/2644663},
	author = {Rácz, Norbert and Kristóf, Gergely and Weidinger, Tamás and Balogh, Miklós},
	booktitle = {Proceedings of the 6th International Conference on Urban Air Quality},
	unique-id = {2644663},
	year = {2007},
	pages = {52-55},
	orcid-numbers = {Kristóf, Gergely/0000-0001-7572-6875; Weidinger, Tamás/0000-0001-7500-6579}
}

@CONFERENCE{MTMT:2644662,
	title = {Adaptation of pressure based CFD solvers to urban heat island convection problem},
	url = {https://m2.mtmt.hu/api/publication/2644662},
	author = {Kristóf, Gergely and Rácz, Norbert and Balogh, Miklós},
	booktitle = {Proceedings of the 6th International Conference on Urban Air Quality},
	unique-id = {2644662},
	year = {2007},
	pages = {76-79},
	orcid-numbers = {Kristóf, Gergely/0000-0001-7572-6875}
}

@inproceedings{MTMT:1326655,
	title = {A városi hősziget által generált konvekció modellezése általános célú áramlástani szoftverrel − összehasonlítás kisminta kísérletekkel},
	url = {https://m2.mtmt.hu/api/publication/1326655},
	author = {Kristóf, Gergely and Rácz, Norbert and Bányai, T and Gál, Tamás Mátyás and Unger, János and Weidinger, Tamás},
	booktitle = {Felhőfizika és mikrometeorológia},
	unique-id = {1326655},
	year = {2007},
	pages = {95-104},
	orcid-numbers = {Kristóf, Gergely/0000-0001-7572-6875; Gál, Tamás Mátyás/0000-0002-1761-3239; Unger, János/0000-0002-0637-0091; Weidinger, Tamás/0000-0001-7500-6579}
}