TY - JOUR A1 - Benim, Ali Cemal A1 - Pasqualotto, E. T1 - Investigation into the computational modelling of diesel engine side injection systems JF - International Journal of Computer Applications in Technology KW - Numerische Strömungssimulation KW - Dieselmotor KW - Einspritzanlage Y1 - 1998 U6 - https://doi.org/10.1504/IJCAT.1998.062199 SN - 0952-8091 VL - 11 IS - 3-5 SP - 211 EP - 218 PB - Inderscience 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 - 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 - Senthur, N.S. A1 - Anand, C A1 - Ramesh Kumar, M A1 - Elumalai, P.V. A1 - Shajahan, Mohamed Iqbal A1 - Benim, Ali Cemal A1 - Nasr, Emad Abouel A1 - Hussein, H.M.A. A1 - Parthasarathy, M. T1 - Influence of cobalt chromium nanoparticles in homogeneous charge compression ignition engine operated with citronella oil JF - Energy Science & Engineering KW - General Energy KW - Safety, Risk, Reliability and Quality KW - DOAJ Y1 - 2022 U6 - https://doi.org/10.1002/ese3.1088 SN - 2050-0505 VL - 10 IS - 4 SP - 1251 EP - 1263 PB - Wiley 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 - Mandal, Dipak Kumar A1 - Biswas, Nirmalendu A1 - Manna, Nirmal K A1 - Benim, Ali Cemal T1 - Impact of chimney divergence and sloped absorber on energy efficacy of a solar chimney power plant (SCPP) JF - Ain Shams Engineering Journal N2 - A numerical study is carried out meticulously to scrutinize the impact of different shapes of chimneys like circular (outer dia, dc), convergent (outer dia, 0.5dc), divergent (outer dia, 1.5dc), sudden contraction (outer dia, 0.5dc), and sudden expansion (outer dia, 1.5dc) on the performance of an SCPP. Furthermore, the parametric impact with different chimney divergence angles (CDA, ϕ), and ground absorber slope angle (GSA, γ) on the SCPP performance is also scrutinized. Optimum divergence angle (ϕ=+0.75◦) enhances the power generation up to ~ 47% (76 kW) with a horizontal ground absorber surface. An increase or decrease in CDA lessens the power generation. With a sloped ground absorber angle γ=0.6◦, the gain in power generation is 60% (82 kW). The study of combination of ground sloped absorber (γ=0.6◦) and divergent chimney (ϕ=+0.75◦) shows enhancement of the power generation upto 80% (92 kW) more than the classical Manzaranes plant. KW - Solar chimney power plant (SCPP) KW - Chimney divergence angle KW - Sloped absorber surface KW - Power generation KW - Efficiency KW - Regression analysis KW - DEAL KW - HSD Publikationsfonds Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:due62-opus-42410 SN - 2090-4495 PB - Elsevier ER - TY - JOUR A1 - Maqableh, A. M. A1 - Ammourah, S. A. A1 - Khadrawi, A. F. A1 - Al-Nimr, M. A. A1 - Benim, Ali Cemal T1 - Hydrodynamics behaviour of a fluid flow in micro-venturi JF - Candian Journal of Physics Y1 - 2012 U6 - https://doi.org/10.1139/p11-145 VL - 90 IS - 1 SP - 83 EP - 89 PB - Canadian Science Publishing ER - TY - JOUR A1 - Maqableh, A. M. A1 - Khadrawi, A. F. A1 - Nimr, M. AlA. A1 - Ammourah, S. A. A1 - Benim, Ali Cemal T1 - Heat transfer characteristics of parallel and counter flow micro-channel heat exchangers with varying wall resistance JF - Progress in Computational Fluid Dynamics, An International Journal Y1 - 2011 U6 - https://doi.org/10.1504/pcfd.2011.042183 VL - 11 IS - 5 PB - inderscience ER - TY - CHAP A1 - Bhattacharyya, Suvanjan A1 - Jain, Naman A1 - Bhatt, Tapasvi A1 - Ghosh, Soumya A1 - Benim, Ali Cemal T1 - Heat Transfer Augmentation in a Mini-channel Using Magnetic Nanofluid and Magnetic Vortex 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 - Wärmeübertragung KW - Numerische Strömungssimulation KW - Laminare Strömung KW - Magnetische Flüssigkeit KW - Magnetischer Flussschlauch Y1 - 2024 SN - 9783031666087 U6 - https://doi.org/10.1007/978-3-031-66609-4_1 SN - 2195-4356 VL - 2 SP - 3 EP - 11 PB - Springer Nature CY - Cham ER - TY - JOUR A1 - Bhattacharyya, Suvanjan A1 - Chattopadhyay, Himadri A1 - Banerjee, Arnab A1 - Benim, Ali Cemal T1 - Heat transfer and flow field in a circular twisted channel JF - MATEC Web of Conferences Y1 - 2018 U6 - https://doi.org/10.1051/matecconf/201824001005 VL - 240 PB - edp sciences ER -