Large Eddy Simulations of atomization and evaporation of liquid fuel sprays in diesel engine conditions are performed with stochastic breakup and non-equilibrium droplet heat and mass transfer models. The size and number density of the droplets generated by the breakup model are assumed to be governed by a Fokker-Planck equation, describing the evolution of the {PDF} of droplet radii. The fragmentation intensity spectrum is considered to be Gaussian and the scale of Lagrangian relative velocity fluctuations is included in the breakup frequency calculations. The aerodynamic interactions of droplets in the dense part of the spray are modeled by correcting the relative velocity of droplets in the wake of other droplets. The stochastic breakup model is employed together with the wake interaction model for simulations of non-evaporating and evaporating sprays in various gas temperature and pressure conditions. The predicted results for physical spray parameters, such as the spray penetration length are found to be in good agreement with the available experimental data.

1 aIrannejad, Abolfazl1 aJaberi, Farhad uhttp://papers.sae.org/2013-01-1101/00506nas a2200109 4500008004100000245010300041210006900144260002600213100001700239700001500256856012500271 2013 eng d00aLarge Eddy Simulation of Spray Mixing and Combustion with Two-Phase Filtered Mass Density Function0 aLarge Eddy Simulation of Spray Mixing and Combustion with TwoPha aSan Diego, California1 aIrannejad, A1 aJaberi, F. uhttps://icer.msu.edu/research/publications/large-eddy-simulation-spray-mixing-combustion-two-phase-filtered-mass-density00562nas a2200133 4500008004100000245012600041210006900167490001200236100002000248700001600268700001500284700001500299856011400314 2013 eng d00aLarge-Eddy Simulations of Turbulent Flows in Internal Combustion Engines, International Journal of Heat and Mass Transfer0 aLargeEddy Simulations of Turbulent Flows in Internal Combustion 0 vVol. 601 aBanaeizadeh, A.1 aAfshari, A.1 aSchock, H.1 aJaberi, F. uhttps://icer.msu.edu/research/publications/large-eddy-simulations-turbulent-flows-internal-combustion-engines00465nas a2200097 4500008004100000245008400041210006900125260003100194100001700225856012500242 2012 eng d00aLessons Learned When Building a Greenfield High Performance Computing Ecosystem0 aLessons Learned When Building a Greenfield High Performance Comp aSan Diego, California, USA1 aKeen, Andrew uhttps://icer.msu.edu/research/publications/lessons-learned-when-building-greenfield-high-performance-computing-ecosystem00554nas a2200145 4500008004100000245009200041210006900133300001400202490000700216100002100223700001300244700002000257700001700277856011400294 2011 eng d00aLong-term differences in tillage and land use affect intra-aggregate pore heterogeneity0 aLongterm differences in tillage and land use affect intraaggrega a1658-16660 v751 aKravchenko, A.N.1 aWang, W.1 aSmucker, A.J.M.1 aRivers, M.L. uhttps://icer.msu.edu/research/publications/long-term-differences-tillage-land-use-affect-intra-aggregate-pore00481nas a2200121 4500008004100000245008100041210006900122260001200191490000600203100001800209700002000227856011200247 2010 eng d00aA landscape and climate data logistic model of tsetse distributions in Kenya0 alandscape and climate data logistic model of tsetse distribution c07/20100 v51 aMoore, Nathan1 aMessina, Joseph uhttps://icer.msu.edu/research/publications/landscape-climate-data-logistic-model-tsetse-distributions-kenya00493nas a2200109 4500008004100000245008500041210006900126260002500195100002200220700001700242856012400259 2010 eng d00aLarge -Scale Simulations of Incident Shock-Turbulent Boundary Layer Interactions0 aLarge Scale Simulations of Incident ShockTurbulent Boundary Laye aOrlando, FLc01/20101 aJammalamadaka, A.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/large-scale-simulations-incident-shock-turbulent-boundary-layer-interactions01408nas a2200181 4500008004100000245009500041210006900136260001200205300001400217490000700231520071100238653009300949653000801042100001701050700001901067700001701086856012301103 2010 eng d00aLarge-Eddy Simulations of Turbulent Methane Jet Flames with Filtered Mass Density Function0 aLargeEddy Simulations of Turbulent Methane Jet Flames with Filte c05/2010 a2551-25620 v533 aThe filtered mass density function (FMDF) model (Jaberi et al. 1999 [1]) is employed for large eddy simulations (LES) of “high speed” partially-premixed methane jet flames with the “flamelet” and “finite-rate” kinetics models. The FMDF is the joint probability density function (PDF) of the scalars and is determined via the solution of a set of stochastic differential equations. The LES/FMDF is implemented using a highly scalable, parallel hybrid Eulerian–Lagrangian numerical scheme. The LES/FMDF results are shown to compare well with the experimental data for all flow conditions when “appropriate” reaction and mixing models are employed.

10aFiltered mass density function; PDF methods; Monte-Carlo simulations; Methane jet flames10aLES1 aYaldizli, M.1 aMehravaran, K.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/large-eddy-simulations-turbulent-methane-jet-flames-filtered-mass-density-001381nas a2200133 4500008004100000245006700041210006600108260003100174520088700205100001101092700001701103700002001120856010701140 2010 eng d00aLarge-Scale Simulations of Supersonic Turbulent Reacting Flows0 aLargeScale Simulations of Supersonic Turbulent Reacting Flows aOrlando, FLbAIAAc01/20103 aThe scalar filtered mass density function (FMDF) is further developed and employed for large-eddy simulations (LES) of high speed turbulent flows in complex geometries. LES/FMDF is implemented via an efficient, hybrid numerical method. In this method, the filtered compressible Navier-Stokes equations in curvilinear coordinate systems are solved with a generalized, high-order, multi-block, compact differencing scheme. Turbulent mixing and combustion are modeled with the FMDF. The LES/FMDF method is used for simulations of isotropic turbulent flow in a piston-cylinder assembly, the flow in a shock tube and a supersonic co-axial helium-air jet. The critical role of pressure in the FMDF equation when applied to compressible flows is studied. It is shown that LES/FMDF is reliable and is able to simulate compressible turbulent mixing and combustion in supersonic flows.

1 aLi, Z.1 aJaberi, F.A.1 aBanaeizadeh, A. uhttps://icer.msu.edu/research/publications/large-scale-simulations-supersonic-turbulent-reacting-flows00963nas a2200289 4500008004100000245007500041210006900116300001200185490000900197653001400206653002500220653003000245653002400275653002200299653002300321653001300344653001400357653001500371653003700386653001900423653004100442100001900483700001900502700002600521700001700547856010900564 2010 eng d00aLocal and Global Radiative Feedback from Population III Star Formation0 aLocal and Global Radiative Feedback from Population III Star For a128-1330 v129410aDistances10aPopulation III stars10aPre-main sequence objects10aprotostellar clouds10aradial velocities10aradiative transfer10aredshift10aredshifts10ascattering10aspatial distribution of galaxies10astar formation10ayoung stellar objects and protostars1 aO'Shea, B., W.1 aWhalen, D., J.1 aWhalen, Bromm, {D. J.1 aYoshida}, N. uhttps://icer.msu.edu/research/publications/local-global-radiative-feedback-population-iii-star-formation01283nas a2200133 4500008004100000245009500041210006900136260005900205520071100264100001700975700001900992700001701011856012101028 2009 eng d00aLarge-Eddy Simulations of Turbulent Methane Jet Flames with Filtered Mass Density Function0 aLargeEddy Simulations of Turbulent Methane Jet Flames with Filte aAnn Arbor, MichiganbThe Combustion Institutec05/20093 aThe filtered mass density function (FMDF) model (Jaberi et al. 1999 [1]) is employed for large eddy simulations (LES) of “high speed” partially-premixed methane jet flames with the “flamelet” and “finite-rate” kinetics models. The FMDF is the joint probability density function (PDF) of the scalars and is determined via the solution of a set of stochastic differential equations. The LES/FMDF is implemented using a highly scalable, parallel hybrid Eulerian–Lagrangian numerical scheme. The LES/FMDF results are shown to compare well with the experimental data for all flow conditions when “appropriate” reaction and mixing models are employed.

1 aYaldizli, M.1 aMehravaran, K.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/large-eddy-simulations-turbulent-methane-jet-flames-filtered-mass-density01565nas a2200121 4500008004100000245005800041210005700099260007700156520108400233100001101317700001701328856009801345 2009 eng d00aLarge-Scale Simulations of High Speed Turbulent Flows0 aLargeScale Simulations of High Speed Turbulent Flows aOrlando, FLbAmerican Institute of Aeronautics and Astronauticsc01/20093 aThis paper briefly describes a new class of high-order Monotonicity-Preserving (MP) finite difference methods recently developed for direct numerical simulation (DNS) and large-eddy simulation (LES) of high-speed turbulent flows. The MP method has been implemented together with high-order compact (COMP) and weighted essentially non- oscillatory (WENO) methods in a generalized three-dimensional (3D) code and has been applied to various 1D, 2D and 3D problems. For the LES, compressible versions of the gradient-based subgrid-scale closures are employed. Detailed and extensive analysis of various flows indicates that MP schemes have less numerical dissipation and faster grid convergence than WENO schemes. Simulations conducted with high-order MP schemes preserve sharp changes in flow variables without spurious oscillations and capture the turbulence at the smallest simulated scales. The non-conservative form of the scalar equation solved with MP schemes are shown to generate the same results as COMP schemes for supersonic mixing problems involving shock waves.

1 aLi, Z.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/large-scale-simulations-high-speed-turbulent-flows02843nas a2200157 4500008004100000245022400041210006900265260001200334300001400346490000800360520214900368100001902517700001602536700001402552856011902566 2009 eng d00aLeft-Eigenstate Completely Renormalized Equation-of-motion Coupled-Cluster Methods: Review of Key Concepts, Extension to Excited States of Open-Shell Systems, and Comparison with Electron-Attached and ionized Approaches0 aLeftEigenstate Completely Renormalized Equationofmotion CoupledC c11/2009 a3268-33040 v1093 aThe recently proposed left-eigenstate completely renormalized (CR) coupled-cluster (CC) method with singles, doubles, and noniterative triples, termed CR-CC(2,3) Piecuch and Włoch, J Chem Phys, 2005, 123, 224105; Piecuch et al. Chem Phys Lett, 2006, 418, 467 and the companion CR-EOMCC(2,3) methodology, which has been previously applied to singlet excited states of closed-shell molecular systems Włoch et al. Mol Phys, 2006, 104, 2149 and in which relatively inexpensive noniterative corrections due to triple excitations derived from the biorthogonal method of moments of CC equations (MMCC) are added to the CC singles and doubles (CCSD) or equation-of-motion (EOM) CCSD energies, have been extended to excited states of open-shell species. The resulting highly efficient computer codes for the open-shell CR-EOMCC(2,3) approach exploiting the recursively generated intermediates and fast matrix multiplication routines have been developed and interfaced with the GAMESS package, enabling CR-EOMCC(2,3) calculations for singlet as well as nonsinglet ground and excited states of closed- and open-shell systems using the restricted Hartree–Fock or restricted open-shell Hartree–Fock references. A number of important mathematical and algorithmic details related to formal aspects and computer implementation of the CR-EOMCC(2,3) method have been discussed, in addition to overviewing the key concepts behind the CR-EOMCC(2,3) and biorthogonal MMCC methodologies for ground and excited states, and the numerical results involving low-lying states of the CH, CNC, C2N, N3, and NCO species, including states dominated by two-electron transitions, have been presented. The results of the CR-EOMCC(2,3) calculations have been compared with other CC/EOMCC approaches, including the EOMCCSD and EOMCC singles, doubles, and triples methods, and their full and active-space valence counterparts based on the electron-attached and ionized EOMCC methodologies, and the predecessor of CR-EOMCC(2,3) termed CR-EOMCCSD(T) Kowalski and Piecuch, J Chem Phys, 2004, 120, 1715. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009

1 aPiecuch, Piotr1 aGour, J., R1 aWloch, M. uhttps://icer.msu.edu/research/publications/left-eigenstate-completely-renormalized-equation-motion-coupled-cluster01658nas a2200133 4500008004100000245006400041210006300105260005900168520114000227100002001367700001901387700001701406856010101423 2009 eng d00aLES/FMDF of Spray Combustion in Internal Combustion Engines0 aLESFMDF of Spray Combustion in Internal Combustion Engines aAnn Arbor, MichiganbThe Combustion Institutec05/20063 aThe two-phase filtered mass density function (FMDF) model is employed for large-eddy simulation (LES) of turbulent spray combustion in internal combustion (IC) engines. The LES/FMDF is implemented with an efficient, hybrid numerical method. In this method, the filtered compressible Navier-Stokes equations in curvilinear coordinate systems are solved with a generalized, high-order, multi-block, compact differencing scheme. The spray and the FMDF are implemented with Lagrangian methods. The LES/FMDF methodology has been used for simulations of turbulent combustion in a rapid compression machine (RCM) and in a direct-injection spark-ignition (DISI) engine. For both RCM and DISI engine, the complex interactions among turbulent velocity, fuel droplets and combustion are shown to be well captured with the LES/FMDF. The results for the DISI engine indicate that the size, velocity, evaporation and combustion of the sprayed fuel droplets are strongly affected by the unsteady, vortical motions generated by the incoming air during the intake stroke. In turn, the droplets are found to change the in-cylinder flow structure.

1 aBanaeizadeh, A.1 aSchock, Harold1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/les-fmdf-spray-combustion-internal-combustion-engines01687nas a2200157 4500008004100000245009400041210006900135260001200204490000800216520112100224100001201345700001901357700001601376700001501392856012201407 2009 eng d00aLocal Correlation Calculations Using Standard and Renormalized Coupled-Cluster Approaches0 aLocal Correlation Calculations Using Standard and Renormalized C c09/20090 v1313 ahe linear scaling local correlation approach, termed “cluster-in-molecule” (CIM), is extended to the coupled-cluster (CC) theory with singles and doubles (CCSD) and CC methods with singles, doubles, and noniterative triples, including CCSD(T) and the completely renormalized CR-CC(2,3) approach. The resulting CIM-CCSD, CIM-CCSD(T), and CIM-CR-CC(2,3) methods are characterized by (i) the linear scaling of the CPU time with the system size, (ii) the use of orthonormal orbitals in the CC subsystem calculations, (iii) the natural parallelism, (iv) the high computational efficiency, enabling calculations for much larger systems and at higher levels of CC theory than previously possible, and (v) the purely noniterative character of local triples corrections. By comparing the results of the canonical and CIM-CC calculations for normal alkanes and water clusters, it is shown that the CIM-CCSD, CIM-CCSD(T), and CIM-CR-CC(2,3) approaches accurately reproduce the corresponding canonical CC correlation and relative energies, while offering savings in the computer effort by orders of magnitude.

1 aLi, Wei1 aPiecuch, Piotr1 aGour, J., R1 aLi, Shuhua uhttps://icer.msu.edu/research/publications/local-correlation-calculations-using-standard-renormalized-coupled-cluster02324nas a2200157 4500008004100000245021700041210007300258260001200331300001200343490000800355520162000363100001401983700001601997700001902013856013402032 2009 eng d00aLow-Lying Valence Excited States of CNC, C₂N, N₃ and NCO Studied Using the Electron-Attached and Ionized Symmetry-Adapted Cluster Configuration-Interaction and Equation-of-Motion Coupled-Cluster Methodologies0 aLowLying Valence Excited States of CNC C₂N N₃ and NCO Studied Us c04/2009 a871-8800 v1073 aLow-lying valence excited states of four open-shell triatomic molecules, CNC, C2N, N3, and NCO, are investigated using the electron-attached (EA) and ionized (IP) symmetry-adapted-cluster configuration-interaction (SAC-CI) general-R as well as the full and active-space EA and IP equation-of-motion coupled-cluster (EOMCC) methods. A comparison is made with experiment and with the results of the completely renormalized (CR) CC calculations with singles, doubles, and non-iterative triples defining the CR-CC(2,3) approach. Adiabatic excitation energies of the calculated states are in reasonable agreement with the experimental values, provided that the 3-particle-2-hole (3p-2h) components in the electron attaching operator, as in the EA SAC-CI SDT-R and EA EOMCCSD(3p-2h) approaches, are included in the calculations for the excited states of C2N and CNC which have a predominantly two-electron character. The results also reveal that the active-space EA/IP EOMCC schemes with up to 3p-2h/3h-2p excitations are able to accurately reproduce the results of their much more expensive parent methods while requiring significantly less computational effort. Furthermore, the more 'black-box' CR-CC(2,3) approach calculates the lowest state of each symmetry with the same accuracy as that obtained with the EA/IP SAC-CI SDT-R and EA/IP EOMCCSD(3p-2h/3h-2p) methods, confirming the significance of higher-order correlation effects in obtaining an accurate description of excited states of radicals, particularly the valence excited states of the CNC and C2N species dominated by two-electron processes.

1 aEhara, M.1 aGour, J., R1 aPiecuch, Piotr uhttps://icer.msu.edu/research/publications/low-lying-valence-excited-states-cnc-c%E2%82%82n-n%E2%82%83-nco-studied-using-electron00471nas a2200121 4500008004100000245006500041210006500106260002000171100001600191700002000207700001700227856010500244 2008 eng d00aLarge Eddy Simulation of High Speed Turbulent Reacting Flows0 aLarge Eddy Simulation of High Speed Turbulent Reacting Flows aHawaiic12/20081 aZhaorui, Li1 aBanaeizadeh, A.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/large-eddy-simulation-high-speed-turbulent-reacting-flows01959nas a2200157 4500008004100000020002200041245006000063210006000123260003800183520141500221100002001636700001601656700001701672700001501689856009701704 2008 eng d a978-0-7918-4327-700aLarge Eddy Simulations of Turbulent Flows in IC Engines0 aLarge Eddy Simulations of Turbulent Flows in IC Engines aBrooklyn, New YorkbASMEc08/20083 aA new computational methodology is developed and tested for large eddy simulation (LES) of turbulent flows in internal combustion (IC) engines. In this methodology, the filtered compressible Navier-Stokes equations in curvilinear coordinate systems are solved via a generalized, high-order, multi-block, compact differencing scheme and various subgrid-scale (SGS) stress closures. Both reacting and nonreacting flows with and without spray are considered. The LES models have been applied to a piston-cylinder assembly with a stationary open valve and harmonically moving flat piston. The flow in a direct-injection spark-ignition (DISI) engine is also considered. It is observed that during the intake stroke of the engine operation, large-scale unsteady turbulent flow motions are developed behind the intake valves. The physical features of these turbulent motions and the ability of LES to capture them are studied and tested by simulating the flow in a simple configuration involving a stationary valve. The flow statistics predicted by LES are shown to compare well with the available experimental data. The DISI configuration includes all the complexities involved in a realistic single-cylinder IC engine, such as the complex geometry, moving valves, moving piston, spray and combustion. The spray combustion is simulated with the recently developed two-phase filtered mass density (FMDF) model.

1 aBanaeizadeh, A.1 aAfshari, A.1 aJaberi, F.A.1 aSchock, H. uhttps://icer.msu.edu/research/publications/large-eddy-simulations-turbulent-flows-ic-engines00522nas a2200121 4500008004100000050001900041245006500060210006400125260007800189100001700267700001100284856010500295 2008 eng d aAIAA 2008-115400aLarge Eddy Simulations of Two-Phase Turbulent Reacting Flows0 aLarge Eddy Simulations of TwoPhase Turbulent Reacting Flows aReno, NevadabAMERICAN INSTITUTE OF AERONAUTICS AND ASTRONAUTICSc01/20081 aJaberi, F.A.1 aLi, Z. uhttps://icer.msu.edu/research/publications/large-eddy-simulations-two-phase-turbulent-reacting-flows01219nas a2200169 4500008004100000245007600041210006900117260001100186300001200197490000700209520061500216653003100831653004000862100001600902700001700918856011400935 2008 eng d00aLarge-Eddy Simulation of a Dispersed Particle-Laden Turbulent Round Jet0 aLargeEddy Simulation of a Dispersed ParticleLaden Turbulent Roun c2/2008 a683-6950 v513 aThe numerical results obtained by large-eddy simulation (LES) of a particle-laden axisymmetric turbulent jet are compared with the available experimental data. The results indicate that with a new stochastic subgrid-scale (SGS) closure, the effects of the particles on the carrier gas and those of the carrier gas on the particles are correctly captured by the LES. Additional numerical experiments are conducted and used to investigate the effects of particle size, mass-loading ratio, and other flow/particle parameters on the statistics of both the carrier gas phase and the particle dispersed phase.

10aParticle-laden jet; dilute10atwo-phase flows; turbulent jet; LES1 aAlmeida, T.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/large-eddy-simulation-dispersed-particle-laden-turbulent-round-jet02380nas a2200169 4500008004100000245007800041210006900119260001200188300001400200490000700214520170600221653001501927653012301942100001602065700001702081856011202098 2008 eng d00aLarge-Eddy Simulation of Turbulent Flow in an Axisymmetric Dump Combustor0 aLargeEddy Simulation of Turbulent Flow in an Axisymmetric Dump C c07/2008 a1576-15920 v463 aA hybrid Eulerian–Lagrangian, mathematical/computational methodology is developed and evaluated for large- eddy simulations of turbulent combustion in complex geometries. The formulation for turbulence is based on the standard subgrid-scale stress models. The formulation for subgrid-scale combustion is based on the filtered mass density function and its equivalent stochastic Lagrangian equations. An algorithm based on high-order compact differencing on generalized multiblock grids is developed for numerical solution of the coupled Eulerian–Lagrangian equations. The results obtained by large-eddy simulations/filtered mass density function show the computational method to be more efficient than existing methods for similar hybrid systems. The consistency, convergence, and accuracy of the filtered mass density function and its Lagrangian–Monte Carlo solver is established for both reacting and nonreacting flows in a dump combustor. The results show that the finite difference and the Monte Carlo numerical methods employed are both accurate and consistent. The results for a reacting premixed dump combustor also agree well with available experimental data. Additionally, the results obtained for other nonreacting turbulent flows are found to be in good agreement with the experimental and high-order numerical data. Filtered mass density function simulations are performed to examine the effects of boundary conditions, subgrid-scale models, as well as physical and geometrical parameters on dump-combustor flows. The results generated for combustors with and without an inlet nozzle are found to be similar as long as appropriate boundary conditions are employed.

10acombustion10aGas turbine; modeling; combustion chamber; Monte Carlo method; Lagragian Method; turbulent flow; large eddy simulation1 aAfshari, A.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/large-eddy-simulation-turbulent-flow-axisymmetric-dump-combustor01318nas a2200133 4500008004100000245006100041210006000102260003200162520086300194100001601057700001701073700001901090856007501109 2007 eng d00aLES/FMDF of Turbulent Combustion in Complex Flow Systems0 aLESFMDF of Turbulent Combustion in Complex Flow Systems aReno, NevadabAIAAc01/20073 aA high-order Lagrangian/Eulerian method based on the the filtered mass density func- tion (FMDF) for subgrid-scale (SGS) combustion closure was developed to perform large eddy simulation (LES) of turbulent reacting flows in complex geometrical configurations in multi-block structured grids. In particular, an efficient algorithm has been developed to search and locate particles in multi-block, hexahedral-structured grid system. Also, the consistency, convergence, and accuracy of the FMDF and the Monte Carlo solution of its equivalent stochastic differential equations were assessed. The consistency between Eulerian and Lagrangian fields were established for a reacting flow in a dump combustor. The results obtained for a reacting flow in an axisymmetric, premixed dump-combustor, were found to compare favorably with measured experimental data.

1 aAfshari, A.1 aJaberi, F.A.1 aShih, T., I-P. uhttps://icer.msu.edu/lesfmdf-turbulent-combustion-complex-flow-systems