A multicomponent droplet evaporation model which discretizes the one-dimensional mass and temperature profiles inside a droplet with a finite volume method has been developed and implemented into a large-eddy simulation ({LES)} model for spray simulations. The {LES} and multicomponent models were used along with the {KH-RT} secondary droplet breakup model to simulate realistic fuel sprays in a closed vessel. The effect of various spray and ambient gas parameters on the liquid penetration length of different single component and multicomponent fuels was investigated. The numerical results indicate that the spray penetration length decreases non-linearly with increasing gas temperature or pressure and is less sensitive to changes in ambient gas conditions at higher temperatures or pressures. The spray models and {LES} were found to predict the experimental results for n-hexadecane and two multicomponent surrogate diesel fuels reasonably well.

1 aSrivastava, S.1 aSchock, H.1 aJaberi, F. uhttp://papers.sae.org/2013-01-1603/00561nas a2200157 4500008004100000245006000041210006000101260003500161300001100196490000800207100001700215700002900232700002200261700002000283856010000303 2012 eng d00aNanomechanical energy storage in twisted nanotube ropes0 aNanomechanical energy storage in twisted nanotube ropes bAmerican Physical SocietycDec a2555010 v1091 aTeich, David1 aFthenakis, Zacharias, G.1 aSeifert, Gotthard1 aTománek, David uhttps://icer.msu.edu/research/publications/nanomechanical-energy-storage-twisted-nanotube-ropes00587nas a2200145 4500008004100000245011300041210006900154300001100223490000800234100001800242700001500260700002300275700002000298856012300318 2011 eng d00aNanoconfinement effects on the reversibility of hydrogen storage in ammonia borane: A first-principles study0 aNanoconfinement effects on the reversibility of hydrogen storage a2145010 v1341 aChang, Kiseok1 aKim, Eunja1 aWeck, Philippe, F.1 aTománek, David uhttps://icer.msu.edu/research/publications/nanoconfinement-effects-reversibility-hydrogen-storage-ammonia-borane-first00695nas a2200181 4500008004100000245010800041210006900149300000800218490000800226653002800234653002500262653003000287100001800317700002000335700001800355700001900373856012100392 2011 eng d00aThe Nature of the Warm/Hot Intergalactic Medium. I. Numerical Methods, Convergence, and O VI Absorption0 aNature of the WarmHot Intergalactic Medium I Numerical Methods C a6-+0 v73110acosmology: observations10aintergalactic medium10aquasars: absorption lines1 aSmith, B., D.1 aHallman, E., J.1 aShull, J., M.1 aO'Shea, B., W. uhttps://icer.msu.edu/research/publications/nature-warm-hot-intergalactic-medium-i-numerical-methods-convergence-o-vi00483nas a2200109 4500008004100000245009600041210006900137490000700206100001700213700002000230856012300250 2010 eng d00aNon-Equilibrium Molecular Dynamics Study of Thermal Energy Transport in Au-SAM-Au Junctions0 aNonEquilibrium Molecular Dynamics Study of Thermal Energy Transp0 v531 aLuo, Tengfei1 aLloyd, John, R. uhttps://icer.msu.edu/research/publications/non-equilibrium-molecular-dynamics-study-thermal-energy-transport-au-sam-au01480nas a2200121 4500008004100000245008700041210006900128260003100197520098000228100001101208700001701219856012201236 2010 eng d00aNumerical Investigations of Shock-Turbulence Interactions in a Planar Mixing Layer0 aNumerical Investigations of ShockTurbulence Interactions in a Pl aOrlando, FLbAIAAc01/20103 aDirect numerical simulation (DNS) and large-eddy simulation (LES) of spatially developing supersonic mixing layer, interacting with an oblique shock wave are conducted with a new high-order Monotonicity-Preserving scheme. Without the incident shock, the mixing layer grows linearly and exhibits self-similar behavior after the transition. With the shock, significant small-scale turbulence is generated just behind the shock. With an increase in shock angle, the intensity of the shock-generated turbulence is increased and its peak position shifts away from the mixing layer centerline. The effects of turbulence on the shock are also shown to be very significant, such that normal shocklets and large adverse pressure gradients are created in some conditions. Comparison with the DNS data indicates that the LES with the modified kinetic energy viscosity (MKEV) subgrid stress model is able to predict the main features of the flow and shock-turbulence interactions.

1 aLi, Z.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/numerical-investigations-shock-turbulence-interactions-planar-mixing-layer00490nas a2200109 4500008004100000245007600041210006900117260005600186100001100242700001700253856011000270 2009 eng d00aA New Model for Numerical Simulations of Two-Phase Turbulent Combustion0 aNew Model for Numerical Simulations of TwoPhase Turbulent Combus aAnn Arbor, MIbNational Combustion Meetingc05/20091 aLi, Z.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/new-model-numerical-simulations-two-phase-turbulent-combustion01341nas a2200145 4500008004100000245009000041210006900131260005000200520075100250100001901001700001901020700001701039700001601056856012301072 2009 eng d00aNumerical Simulation of a Direct-Injection Spark-Ignition Engine with Different Fuels0 aNumerical Simulation of a DirectInjection SparkIgnition Engine w aDetroit, MichiganbSAE Internationalc04/20093 aThis paper focuses on the numerical investigation of the mixing and combustion of ethanol and gasoline in a single-cylinder 3-valve direct-injection spark-ignition engine. The numerical simulations are conducted with the KIVA code with global reaction models. However, an ignition delay model mitigates some of the deficiencies of the global one-step reaction model and is implemented via a two-dimensional look-up table, which was created using available detailed kinetics models. Simulations demonstrate the problems faced by ethanol operated engines and indicate that some of the strategies used for emission control and downsizing of gasoline engines can be employed for enhancing the combustion efficiency of ethanol operated engines.

1 aSrivastava, S.1 aSchock, Harold1 aJaberi, F.A.1 aHung, David uhttps://icer.msu.edu/research/publications/numerical-simulation-direct-injection-spark-ignition-engine-different-fuels00667nas a2200181 4500008004100000245010900041210006900150260003000219300001300249490000600262100001400268700001600282700001400298700001700312700001600329700001700345856012300362 2008 eng d00aNatural selection fails to optimize mutation rates for long-term adaptation on rugged fitness landscapes0 aNatural selection fails to optimize mutation rates for longterm bPublic Library of Science ae10001870 v41 aClune, J.1 aMisevic, D.1 aOfria, C.1 aLenski, R.E.1 aElena, S.F.1 aSanjuán, R. uhttps://icer.msu.edu/research/publications/natural-selection-fails-optimize-mutation-rates-long-term-adaptation-rugged01291nas a2200169 4500008004100000020002600041245012100067210006900188260004600257490000800303520060900311100001900920700002400939700001500963700001700978856012600995 2007 eng d aISBN13: 978084123843500aNew Alternatives for Accurate Electronic Structure Calculations of Potential Energy Surfaces Involving Bond Breaking0 aNew Alternatives for Accurate Electronic Structure Calculations aWashington, DCbAmerican Chemical Sociegy0 v9583 aThe method of moments of coupled-cluster equations (MMCC) is extended to potential energy surfaces involving multiple bond breaking by developing the quasi-variational (QV) and quadratic (Q) variants of the MMCC theory. The QVMMCC and QMMCC methods are related to the extended CC (ECC) theory, in which products involving cluster operators and their deexcitation counterparts mimic the effects of higher-order clusters. The test calculations for N2 show that the QMMCC and ECC methods can provide spectacular improvements in the description of multiple bond breaking by the standard CC approaches.

1 aPiecuch, Piotr1 aPimienta, I., S. O.1 aFan, P.-D.1 aKowalski, K. uhttps://icer.msu.edu/new-alternatives-accurate-electronic-structure-calculations-potential-energy-surfaces-involving-bond01300nas a2200133 4500008004100000245007900041210006900120260005000189520079100239100001701030700001101047700001701058856009101075 2007 eng d00aA New Model for Large Eddy Simulations of Multi-Phase Turbulent Combustion0 aNew Model for Large Eddy Simulations of MultiPhase Turbulent Com aCincinnati, OhiobAIAA/ASME/SAI/ASEEc07/20073 aNumerical simulations of a spray-controlled lean premixed dump combustor are con- ducted via a two-phase large eddy simulation (LES) methodology. In this methodology, the velocity field is obtained by a high-order finite difference method. The subgrid gas- liquid combustion closure is based on the two-phase filtered mass density function (FMDF) method and the spray is modeled with a Lagrangian scheme. The effects of spray, fuel/air composition, and inflow/outflow conditions on the combustion are investigated. It has been found that the main features of the turbulence and combustion inside the dump combustor are very differently modified by the spray for different spray parameters. The LES/FMDF results also indicate the significance of the inflow and outflow conditions.

1 aYaldizli, M.1 aLi, Z.1 aJaberi, J.A. uhttps://icer.msu.edu/new-model-large-eddy-simulations-multi-phase-turbulent-combustion01659nas a2200145 4500008004100000020001800041245007700059210006900136260003700205520113400242100001101376700001701387700001701404856009201421 2007 eng d a0-7918-4803-500aNumerical Simulations of Two-Phase Turbulent Combustion in Spray Burners0 aNumerical Simulations of TwoPhase Turbulent Combustion in Spray aLas Vegas, NevadabASMEc09/20073 aThe complex interactions among turbulence, combustion and spray in liquid-fuel burners are modeled and simulated via a new two-phase Lagrangian-Eulerian-Lagrangian large eddy simulation (LES) methodology. In this methodology, the spray is modeled with a Lagrangian mathematical/computational method which allows two-way mass, momentum and energy coupling between phases. The subgrid gas-liquid combustion is based on the two-phase filtered mass density function (FMDF) that has several advantages over “conventional” two-phase combustion models. The LES/FMDF is employed in conjunction with non-equilibrium reaction and droplet models. Simulations of turbulent combustion in a spray-controlled double-swirl burner are conducted via LES/FMDF. The generated results are used for better understanding of spray combustion in realistic turbulent flow configurations. The effects of spray angle, mass loading ratio, fuel type, droplet size distribution, wall and inflow/outflow conditions on the flow and combustion are investigated. The LES/FMDF predictions are shown to be consistent with the experimental results.

1 aLi, Z.1 aYaldizli, M.1 aJaberi, F.A. uhttps://icer.msu.edu/numerical-simulations-two-phase-turbulent-combustion-spray-burners01919nas a2200181 4500008004100000245010400041210006900145260001200214300001100226490000800237520110200245653019501347100001901542700002101561700001701582700001401599856012401613 2006 eng d00aNon-Iterative Coupled- Cluster Methods Employing Multi-Reference Perturbation Theory Wave Functions0 aNonIterative Coupled Cluster Methods Employing MultiReference Pe c10/2006 a89-1040 v7713 aA new class of non-iterative coupled-cluster (CC) methods, which improve the results of standard CC and equation-of-motion (EOM) CC calculations for ground and excited-state potential energy surfaces along bond breaking coordinates and for excited states dominated by two-electron transitions, is explored. The proposed approaches combine the method of moments of coupled-cluster equations (MMCC), in which the a posteriori corrections due to higher-order correlations are added to standard CC/EOMCC energies, with the multi-reference many-body perturbation theory (MRMBPT), which provides information about the most essential non-dynamic and dynamic correlation effects that are relevant to electronic quasi-degeneracies. The performance of the basic MRMBPT-corrected MMCC approximation, in which inexpensive non-iterative corrections due to triple excitations are added to ground- and excited-state energies obtained with the CC/EOMCC singles and doubles approach, is illustrated by the results of a few test calculations, including bond breaking in HF and H2O, and excited states of CH+.

10aCoupled-cluster theory; Equation-of-motion coupled-cluster methods; Method of moments of coupled-cluster equations; Multi-reference perturbation theory; Non-iterative coupled-cluster methods1 aPiecuch, Piotr1 aLodriguito, M.D.1 aKowalski, K.1 aWloch, M. uhttps://icer.msu.edu/non-iterative-coupled-cluster-methods-employing-multi-reference-perturbation-theory-wave-functions00503nas a2200145 4500008004100000245007200041210006900113300001100182490000700193100001900200700001400219700001900233700001600252856008900268 2006 eng d00aNon-iterative Coupled-Cluster Methods for Excited Electronic States0 aNoniterative CoupledCluster Methods for Excited Electronic State a45-1060 v151 aPiecuch, Piotr1 aWloch, M.1 aLodriguito, M.1 aGour, J., R uhttps://icer.msu.edu/non-iterative-coupled-cluster-methods-excited-electronic-states01726nas a2200157 4500008004100000245013900041210006900180260001200249300001400261490000800275520111600283100001901399700001701418700001701435856011601452 2005 eng d00aNoniterative Corrections to Extended Coupled-Cluster Energies Employing the Generalized Method of Moments of Coupled-Cluster Equations0 aNoniterative Corrections to Extended CoupledCluster Energies Emp c08/2005 a2191-22130 v1033 aIt is shown that the extended coupled-cluster method with singles and doubles (ECCSD) does not suffer from the non-variational collapse observed in the standard CCSD calculations when multiple bond breaking is examined. This interesting feature of the single-reference ECCSD theory is used to design the non-iterative CC methods with singles, doubles and non-iterative triples and quadruples, which provide a highly accurate and variational description of potential energy surfaces involving multiple bond breaking with computational steps that scale as with the system size. This is accomplished with the help of the generalized version of the method of moments of coupled-cluster equations (GMMCC), which can be used to correct the results of non-standard CC calculations, such as ECCSD. The theoretical considerations are illustrated by the preliminary results of the ECCSD-based GMMCC calculations for triple bond breaking in N2. Keywords: Coupled-cluster theory; Extended coupled-cluster method; Method of moments of coupled-cluster equations; Non-iterative coupled-cluster approaches; Bond breaking

1 aPiecuch, Piotr1 aFan, {P.-D.}1 aKowalski, K. uhttps://icer.msu.edu/research/publications/noniterative-corrections-extended-coupled-cluster-energies-employing01746nas a2200217 4500008004100000245008700041210006900128260001200197300001200209490000800221520103700229100001901266700001701285700001601302700001401318700002601332700001701358700001901375700001401394856012001408 2005 eng d00aNuclear Structure Calculations with Coupled-Cluster Methods from Quantum Chemistry0 aNuclear Structure Calculations with CoupledCluster Methods from c04/2005 a299-3080 v7523 aWe present several coupled-cluster calculations of ground and excited states of 4He and 16O employing methods from quantum chemistry. A comparison of coupled cluster results with the results of exact diagonalization of the hamiltonian in the same model space and other truncated shell-model calculations shows that the quantum chemistry inspired coupled cluster approximations provide an excellent description of ground and excited states of nuclei, with much less computational effort than traditional large-scale shell-model approaches. Unless truncations are made, for nuclei like 16O, full-fledged shell-model calculations with four or more major shells are not possible. However, these and even larger systems can be studied with the coupled cluster methods due to the polynomial rather than factorial scaling inherent in standard shell-model studies. This makes the coupled cluster approaches, developed in quantum chemistry, viable methods for describing weakly bound systems of interest for future nuclear facilities.

1 aPiecuch, Piotr1 aDean, D., J.1 aGour, J., R1 aHagen, G.1 aHjorth-Jensen}, M., {1 aKowalski, K.1 aPapenbrock, T.1 aWloch, M. uhttps://icer.msu.edu/research/publications/nuclear-structure-calculations-coupled-cluster-methods-quantum-chemistry