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This study has presented a comprehensive computational fluid dynamics (CFD) analysis of combustion flow in a realistic can combustor, evaluating the influence of various turbulence models on flow, thermal, and species fields. The…

Fluid Dynamics · Physics 2026-05-20 Aishvarya Kumar , Ram Prakash Bharti

A recent rotational flamelet model is developed and tested with an improved framework of detailed chemistry and transport. The rotational flamelet model incorporates the effects of shear strain and vorticity on local flame behavior and is…

Fluid Dynamics · Physics 2024-10-22 Wes Hellwig , Xian Shi , William A. Sirignano

The interaction between an incident shock wave and a Mach-6 undisturbed hypersonic laminar boundary layer over a cold wall is addressed using direct numerical simulations (DNS) and wall-modeled large-eddy simulations (WMLES) at different…

Fluid Dynamics · Physics 2021-02-03 Lin Fu , Michael Karp , Sanjeeb T. Bose , Parviz Moin , Javier Urzay

Flame propagation through a non-volatile solid-fuel suspension is studied using a simplified, time-dependent numerical model that considers the influence of both diffusional and kinetic rates on the particle combustion process. It is…

Lean premixed hydrogen-air flames are strongly affected by thermodiffusive (TD) instabilities, which can alter the flame structure and enhance the local reactivity many-fold. Two recent models (Howarth et al. (Combust.~Flame 253, 2023) and…

We propose a predictive model of the turbulent burning velocity $S_T$ in homogeneous isotropic turbulence (HIT) based on Lagrangian statistics of propagating surfaces. The propagating surfaces with a constant displacement speed are…

Fluid Dynamics · Physics 2020-02-19 Jiaping You , Yue Yang

Direct Numerical Simulations (DNS) of premixed hydrogen-air flames anchored in a fully-developed turbulent channel flow (TCF) are performed at a friction Reynolds number of $\mathrm{Re}_\tau=530$ and thermochemical conditions susceptible to…

Fluid Dynamics · Physics 2025-12-01 Felix Rong , Max Schneider , Hendrik Nicolai , Christian Hasse , Andrea Gruber

The neutrino-heated "gain layer" immediately behind the stalled shock in a core-collapse supernova is unstable to high-Reynolds-number turbulent convection. We carry out and analyze a new set of 19 high-resolution three-dimensional (3D)…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Sean M. Couch , Christian D. Ott

The multiscale nature of turbulent combustion necessitates accurate and computationally efficient methods for direct numerical simulations (DNS). The field has long been dominated by high-order finite differences, which lack the flexibility…

Fluid Dynamics · Physics 2024-01-24 Jack R. C. King

The influence of the small scale ``cellular'' structure of premixed flames on their evolution at larger scales is investigated. A procedure of the space-time averaging of the flow variables over flame cells is introduced. It is proved that…

Fluid Dynamics · Physics 2007-05-23 Kirill A. Kazakov

The present study addresses the reaction zone structure and burning mechanism of unstable detonations. Experiments investigated mainly two-dimensional methane-oxygen cellular detonations in a thin channel geometry. The sufficiently high…

Reported in the paper are results of unsteady three-dimensional direct numerical simulations of laminar and turbulent, lean hydrogen-air, complex-chemistry flames propagating in forced turbulence in a box. To explore the eventual influence…

Fluid Dynamics · Physics 2023-02-24 HsuChew Lee , BuChen Wu , Peng Dai , Minping Wan , Andrei Lipatnikov

The combined influence of elevated pressure and temperature, representative of gas-turbine operating conditions, on lean premixed hydrogen flames is investigated using Direct Numerical Simulations (DNS) of a turbulent jet. Three cases are…

A three-dimensional flamelet model considering vortex stretching with unitary Lewis number is used to simulate diluted hydrogen-oxygen diffusion flames. Non-reacting nitrogen is used as the diluent gas in the fuel stream. Unitary Lewis…

Fluid Dynamics · Physics 2024-10-08 Wes Hellwig , Xian Shi , William A. Sirignano

Direct numerical simulations (DNS) of fully-developed turbulent channel flows for very low Reynolds numbers have been performed with a larger computational box sizes than those of existing DNS. The friction Reynolds number was decreased…

Fluid Dynamics · Physics 2014-09-17 Takahiro Tsukahara , Yohji Seki , Hiroshi Kawamura , Daisuke Tochio

A novel method for analyzing counterflow diffusion flames, inspired by Zurada's sensitivity approach for neural networks, is proposed to identify critical species influencing the heat release rate in combustion. By further analyzing…

Chemical Physics · Physics 2024-07-03 Liang Ji , Kalyanasundaram Seshadri

Direct numerical simulations of turbulent heat transfer in fully-developed channel flows have been performed in a range of friction Reynolds number between 60 and 180, based on the friction velocity and the channel half width $\delta$, with…

Fluid Dynamics · Physics 2014-09-18 Takahiro Tsukahara , Kaoru Iwamoto , Hiroshi Kawamura , Tetsuaki Takeda

We investigate several key questions of plasma heating in open-field regions of the corona that connect to the solar wind. We present results for a model of Alfven-wave-driven turbulence for three typical open magnetic field structures: a…

Solar and Stellar Astrophysics · Physics 2015-10-07 Lauren N. Woolsey , Steven R. Cranmer

The influence of high-enthalpy effects on hypersonic turbulent boundary layers is investigated by means of direct numerical simulations (DNS). A quasi-adiabatic flat-plate air flow at free-stream Mach number equal to 10 is simulated up to…

Fluid Dynamics · Physics 2021-03-31 Donatella Passiatore , Luca Sciacovelli , Paola Cinnella , Giuseppe Pascazio

This work presents a new approach for premixed turbulent combustion modeling based on convolutional neural networks (CNN). We first propose a framework to reformulate the problem of subgrid flame surface density estimation as a machine…

Fluid Dynamics · Physics 2019-08-02 C. J. Lapeyre , A. Misdariis , N. Cazard , D. Veynante , T. Poinsot