TY - CHAP A1 - Rückert, Frank Ulrich A1 - Burhan, Ibrar A1 - Ahmed, Arslan A1 - Hübner, Dirk A1 - Allweyer, Benjamin A1 - Klinger, Friedrich A1 - Benim, Ali Cemal T1 - Development of a Passive Cooling System for a Gearless Wind Energy Generator T2 - Advances in Computational Heat and Mass Transfer Proceedings of the 14th International Conference on Computational Heat and Mass Transfer (ICCHMT 2023), 4-8 September, 2023, Düsseldorf, Germany KW - Numerische Strömungssimulation KW - Windenergie KW - Windturbine KW - Kühlung KW - Wärmeaustauscher Y1 - 2024 SN - 9783031672408 U6 - https://doi.org/10.1007/978-3-031-67241-5_30 SN - 2195-4356 VL - 1 SP - 333 EP - 343 PB - Springer Nature CY - Cham ER - TY - JOUR A1 - Sidharth, K. Pillai A1 - Rajkumar, Mattacaud R. A1 - Chithrakumar, V. K. A1 - Asirvatham, Godson L. A1 - Benim, Ali Cemal A1 - Wogwises, Somchai T1 - Impact of increased outer wall rotation on convection in a vertical annulus with a stationary heated inner cylinder JF - Heat Transfer N2 - The interplay of centrifugal and buoyant forces on convective heat transfer in a vertical annulus formed by rotating adiabatic outer cylinder and stationary heated inner cylinder has been experimentally and numerically investigated. Experiments were performed for rotational speeds corresponding to the rotation parameter ζ in the range of 527 ≤ ζ ≤ 2860, maintaining the heat flux of the heated stationary inner cylinder as 80 W/m2, for radius ratio (η) and aspect ratio of the vertical annulus being 0.614 and 0.052, respectively. The problem was investigated numerically using the commercial computational fluid dynamics package, ANSYS CFX. The numerical methodology has been validated by comparing the numerically predicted average surface Nusselt number with experimentally obtained values. The comparison revealed an enhancement of the thermal performance of the heated stationary inner cylinder in the range 527 ≤ ζ ≤ 1190 due to the increase in turbulence intensity towards the heated inner cylinder. However, when the rotation parameter was increased further in the range 1190 ≤ ζ ≤ 2860, the thermal performance of the stationary heated inner cylinder showed only marginal improvement. The aforementioned thermal behavior of the inner heated stationary cylinder has been explored based on the flow statistics gathered from the numerical simulations. KW - Numerische Strömungssimulation KW - Nusselt-Zahl KW - Statischer Auftrieb KW - Zentrifugalkraft KW - Zylinder (Maschinenbau) KW - Wärmeübertragung Y1 - 2022 U6 - https://doi.org/10.1002/htj.22617 SN - 2688-4534 VL - 51 IS - 7 SP - 6656 EP - 6684 PB - Wiley ER - TY - JOUR A1 - Benim, Ali Cemal A1 - Cagan, Markos A1 - Günes, Dogan T1 - Computational analysis of transient heat transfer in turbulent pipe flow JF - International Journal of Thermal Sciences KW - Turbulenzmodell KW - Wärmeübertragung KW - Numerische Strömungssimulation KW - Turbulente Strömung Y1 - 2004 U6 - https://doi.org/https://doi.org/10.1016/j.ijthermalsci.2004.02.012 SN - 1290-0729 VL - 43 IS - 8 SP - 725 EP - 732 PB - Elsevier ER - TY - JOUR A1 - Benim, Ali Cemal A1 - Brillert, Dieter A1 - Cagan, Markos T1 - Computational investigation of the flow in pre-swirl stator-rotor systems JF - International Journal of Computational Methods N2 - A 3D computational analysis has been applied to investigate direct transfer, pre-swirl systems for gas turbine cooling. Alternative computational procedures have been applied and results have been compared with measurements. Based on these validation studies, strategies for modeling such systems have been proposed. Present results suggest that sufficiently accurate predictions can be obtained using a quasi-steady analysis applying the "frozen rotor" approach for treating the interface between the stationary and rotating domains. KW - Gasturbine KW - Kühlung KW - Numerische Strömungssimulation Y1 - 2004 U6 - https://doi.org/10.1142/S0219876204000125 SN - 0219-8762 VL - 1 IS - 2 SP - 329 EP - 343 PB - World Scientific ER - TY - JOUR A1 - Epple, Bernd A1 - Fiveland, Woody A1 - Krohmer, Bernd A1 - Richards, Galen A1 - Benim, Ali Cemal T1 - Assessment of two-phase flow models for the simulation of pulverized coald combustion JF - Clean Air: International Journal on Energy for a Clean Environment KW - Numerische Strömungssimulation KW - Kohle KW - Verbrennung KW - Zweiphasenströmung Y1 - 2005 U6 - https://doi.org/10.1615/InterJEnerCleanEnv.v6.i3.50 SN - 1561-4417 VL - 6 IS - 3 SP - 267 EP - 287 PB - Begell House ER - TY - JOUR A1 - Benim, Ali Cemal A1 - Stegelitz, P. A1 - Epple, Bernd T1 - Simulation of the two-phase flow in a laboratory coal pulveriser JF - Forschung im Ingenieurwesen KW - Numerische Strömungssimulation KW - Verbrennung KW - Zweiphasenströmung KW - Kohle Y1 - 2005 U6 - https://doi.org/10.1007/s10010-005-0002-4 SN - 0015-7899 VL - 69 IS - 4 SP - 197 EP - 204 PB - Springer Nature ER - TY - JOUR A1 - Kim, Ju Pyo A1 - Schnell, Uwe A1 - Scheffknecht, Günter A1 - Benim, Ali Cemal T1 - Numerical modelling of MILD combustion for coal JF - Progress in Computational Fluid Dynamics KW - Numerische Strömungssimulation KW - Kohle KW - Verbrennung KW - Moderate and Intense Low-Oxygen Dilution Combustion Y1 - 2007 U6 - https://doi.org/10.1504/PCFD.2007.014683 SN - 1468-4349 VL - 7 IS - 6 PB - Inderscience Publishers ER - TY - CHAP A1 - Özman, Cansu A1 - Gül, Fethi A1 - Diederich, Michael A1 - Benim, Ali Cemal A1 - Janoske, Uwe T1 - Computational and Experimental Investigation of Flow and Convective Heat Transfer along Rough Surfaces T2 - Proceedings of CONV-22: Int. Symp. on Convective Heat and Mass Transfer June 5 – 10, 2022, Turkey KW - Numerische Strömungssimulation KW - Wärmeübertragung KW - Rauigkeit KW - Turbulenzmodell Y1 - 2022 U6 - https://doi.org/10.1615/ICHMT.2022.CONV22.590 SP - 447 EP - 454 PB - Begellhouse ER - TY - JOUR A1 - Mabrouk, Riheb A1 - Naji, Hassane A1 - Benim, Ali Cemal A1 - Dhahri, Hacen T1 - A State of the Art Review on Sensible and Latent Heat Thermal Energy Storage Processes in Porous Media: Mesoscopic Simulation JF - Applied Sciences KW - DOAJ Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:due62-opus-40343 VL - 12 IS - 14 PB - MDPI ER - TY - JOUR A1 - Bhattacharyya, Suvanjan A1 - Chattopadhyay, Himadri A1 - Benim, Ali Cemal T1 - Computational investigation of heat transfer enhancement by alternating inclined ribs in tubular heat exchanger JF - Progress in Computational Fluid Dynamics KW - CFD KW - forced convection KW - transitional turbulence KW - inclined ribs KW - heat transfer enhancement Y1 - 2017 U6 - https://doi.org/10.1504/PCFD.2017.088818 SN - 1468-4349 VL - 17 IS - 6 SP - 390 EP - 396 PB - Inderscience Enterprises Limited ER - TY - JOUR A1 - Mabrouk, Riheb A1 - Benim, Ali Cemal A1 - Naji, Hassane A1 - Dhahri, Hacen T1 - Investigation of Pulsed Flow Effects on the Phase Change Within an Open-Cell Metal Foam Using Thermal Lattice Boltzmann Method JF - Transport in Porous Media KW - Thermal lattice Boltzmann method KW - Energetic and exergetic efficiencies KW - Local thermal non-equilibrium KW - Solidification process KW - Melting KW - Porous media KW - Pulsating flow Y1 - 2023 U6 - https://doi.org/10.1007/s11242-023-01903-x SN - 0169-3913 VL - 147 IS - 2 SP - 225 EP - 257 PB - Springer Nature ER - TY - JOUR A1 - Benim, Ali Cemal A1 - Canal, Cansu Deniz A1 - Boke, Yakup Erhan T1 - Computational investigation of oxy-combustion of pulverized coal and biomass in a swirl burner JF - Energy Y1 - 2022 U6 - https://doi.org/10.1016/j.energy.2021.121852 SN - 0360-5442 VL - 238 IS - C PB - Elsevier ER - TY - JOUR A1 - Bhattacharyya, Suvanjan A1 - Benim, Ali Cemal A1 - Chattopadhyay, Himadri A1 - Banerjee, Arnab T1 - Experimental investigation of heat transfer performance of corrugated tube with spring tape inserts JF - Experimental Heat Transfer Y1 - 2019 U6 - https://doi.org/10.1080/08916152.2018.1531955 SN - 0891-6152 VL - 32 IS - 5 SP - 411 EP - 425 PB - Taylor & Francis ER - TY - JOUR A1 - Benim, Ali Cemal T1 - Introducing the “Mathematical Modelling and Numerical Simulation of Combustion and Fire” Section of the Journal Fire JF - fire Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:due62-opus-40257 SN - 2571-6255 VL - 5 IS - 6 PB - MDPI ER - TY - JOUR A1 - Bhattacharyya, Suvanjan A1 - Benim, Ali Cemal A1 - Pathak, Manabendra A1 - Chamoli, Sunil A1 - Gupta, Ashutosh T1 - Thermohydraulic characteristics of inline and staggered angular cut baffle inserts in the turbulent flow regime JF - Journal of Thermal Analysis and Calorimetry Y1 - 2020 U6 - https://doi.org/10.1007/s10973-019-09094-8 SN - 1388-6150 VL - 140 IS - 3 SP - 1519 EP - 1536 PB - Springer Nature ER - TY - JOUR A1 - Pfeiffelmann, Bjorn A1 - Ozman, Cansu A1 - Benim, Ali Cemal A1 - Joos, Franz T1 - Analysis of the effect of nonuniform surface temperature distribution on the performance of a thermoelectric generator JF - Sustainable Energy Technologies and Assessments Y1 - 2022 U6 - https://doi.org/10.1016/j.seta.2022.102375 SN - 2213-1388 VL - 53 IS - A PB - Elsevier ER - TY - JOUR A1 - Biswas, Nirmalendu A1 - Mandal, Dipak Kumar A1 - Manna, Nirmal K. A1 - Benim, Ali Cemal T1 - Enhanced energy and mass transport dynamics in a thermo-magneto-bioconvective porous system containing oxytactic bacteria and nanoparticles: cleaner energy application JF - Energy Y1 - 2023 U6 - https://doi.org/10.1016/j.energy.2022.125775 SN - 0360-5442 VL - 263 IS - B PB - Elsevier ER - TY - JOUR A1 - Benim, Ali Cemal T1 - Investigation into the Computational Analysis of High–Speed Microjet Hydrogen–Air Diffusion Flames JF - Fire N2 - High-speed microjet hydrogen–air diffusion flames are investigated computationally. The focus is on the prediction of the so-called bottleneck phenomenon. The latter has been previously observed as a specific feature of the present flame class and has not yet been investigated computationally. In the configuration under consideration, the nozzle diameter is 0.5 mm and six cases with mean nozzle injection velocities (U) between 306 m/s and 561 m/s are considered. The flow in the nozzle lance is analyzed separately to obtain detailed inlet boundary conditions for the flame calculations. It is confirmed by calculation that the phenomenon is mainly determined by the transition to turbulence in the initial parts of the free jet. The transitional turbulence proves to be the biggest challenge in predicting this class of flames, as the generally available turbulence and turbulent combustion models reach the limits of their validity in transitional flows. In a Reynolds-Averaged Numerical Simulation framework, the Shear Stress Transport model is found to perform better than alternative two-equation models and is used as the turbulence model. By neglecting the interactions between the turbulence and chemistry (no-model approach), it is possible to predict the morphology of the bottleneck flame and its dependence on U qualitatively. However, the position of the bottleneck is overpredicted for U < 561 m/s. The experimental flames in the considered U range are all attached to the nozzle. This is also predicted by the no-model approach. The Eddy Dissipation Concept (EDC) used as the turbulence combustion model predicts, however, lifted flames (with increasing lift-off height as U decreases). With the EDC, no bottleneck morphology is observed for U = 561 m/s. For lower U, the EDC results for the bottleneck position are generally closer to the measurements. It is demonstrated that accuracy in predicting the bottleneck position can be improved by ad hoc modifications of the turbulent viscosity. KW - Turbulenzmodell KW - Diffusionsflamme KW - hydrogen combustion KW - bottleneck flame KW - diffusion flame KW - microjet flame KW - transitional turbulence KW - turbulence modelling KW - combustion modelling Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:due62-opus-46345 SN - 2571-6255 VL - 7 IS - 9 PB - MDPI ER - TY - JOUR A1 - Başaran, Anıl A1 - Benim, Ali Cemal T1 - Condensation Flow of Refrigerants Inside Mini and Microchannels: A Review JF - Applied Sciences N2 - Nowadays, the demand for obtaining high heat flux values in small volumes has increased with the development of technology. Condensing flow inside mini- and microchannels has been becoming a promising solution for refrigeration, HVAC, air-conditioning, heat pumps, heat pipes, and electronic cooling applications. In these applications, employing mini/microchannels in the condenser design results in the working fluid, generally refrigerant, undergoing a phase change inside the mini/microchannels. On the other hand, the reduction in the hydraulic diameter during condensation gives rise to different flow regimes and heat transfer mechanisms in the mini- and microchannels compared to the conventional channels. Therefore, the understanding of fluid flow and heat transfer characteristics during condensation of refrigerant inside mini- and microchannels has been gaining importance in terms of condenser design. This study presents a state-of-the-art review of condensation studies on refrigerants inside mini- and microchannels. The review includes experimental studies as well as correlation models, which are developed to predict condensation heat transfer coefficients and pressure drop. The refrigerant type, thermodynamical performance, and compatibility, as well as the environmental effects of refrigerant, play a decisive role in the design of refrigeration systems. Therefore, the environmental impacts of refrigerants and current regulations against them are also discussed in the present review. KW - Kondensation KW - Druckabfall KW - Kältemittel KW - condensation KW - microchannels KW - minichannels KW - heat transfer coefficient KW - pressure drop KW - refrigerants KW - Wärmeübergangszahl Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:due62-opus-46358 SN - 2076-3417 VL - 14 IS - 7 PB - MDPI ER - TY - JOUR A1 - Zengin, İbrahim A1 - Erdoğan, Beytullah A1 - Benim, Ali Cemal T1 - CFD and Taguchi based optimization of air driven single stage partial admission axial turbine blade profiles JF - Energy KW - Taguchi-Methode KW - Numerische Strömungssimulation KW - Axialturbine KW - Beschaufelung KW - Optimierung KW - Impulse turbine KW - Partial-admission Y1 - 2024 U6 - https://doi.org/10.1016/j.energy.2024.130333 SN - 0360-5442 VL - 290 PB - Elsevier ER -