# # ENZO PROBLEM DEFINITION FILE: AMR Cosmology Simulation including # dark matter and gas, as well as radiative cooling, primordial # hydrogen+helium chemistry (no molecular hydrogen), a uniform # metagalactic radiation background, and star formation and feedback # using an AMR version of the Cen & Ostriker algorithm. # # Written by Brian O'Shea (oshea@msu.edu) # # Note: This file is used by Enzo with the command line # 'enzo.exe -d gas_plus_dm_amr_multiphys.enzo'. Enzo also requires # four binary files that have been generated with inits.exe # and the file gas_plus_dm.inits prior to executing Enzo. # These files are named GridDensity, GridVelocities, # ParticlePositions, and ParticleVelocities. # # define problem # ProblemType = 30 // cosmology simulation TopGridRank = 3 TopGridDimensions = 128 128 128 SelfGravity = 1 // gravity on TopGridGravityBoundary = 0 // Periodic BC for gravity LeftFaceBoundaryCondition = 3 3 3 // same for fluid RightFaceBoundaryCondition = 3 3 3 # # problem parameters # CosmologySimulationOmegaBaryonNow = 0.04 CosmologySimulationOmegaCDMNow = 0.23 CosmologyOmegaMatterNow = 0.27 CosmologyOmegaLambdaNow = 0.73 CosmologySimulationDensityName = GridDensity CosmologySimulationVelocity1Name = GridVelocities CosmologySimulationVelocity2Name = GridVelocities CosmologySimulationVelocity3Name = GridVelocities CosmologySimulationParticlePositionName = ParticlePositions CosmologySimulationParticleVelocityName = ParticleVelocities CosmologySimulationNumberOfInitialGrids = 1 # # define cosmology parameters # ComovingCoordinates = 1 // Expansion ON CosmologyHubbleConstantNow = 0.71 // in km/s/Mpc CosmologyComovingBoxSize = 20.0 // in Mpc/h CosmologyMaxExpansionRate = 0.015 // maximum allowed delta(a)/a CosmologyInitialRedshift = 99.0 // CosmologyFinalRedshift = 0.0 // GravitationalConstant = 1 // this must be true for cosmology # # set I/O and stop/start parameters # CosmologyOutputRedshift[0] = 99.0 CosmologyOutputRedshift[1] = 10.0 CosmologyOutputRedshift[2] = 5.0 CosmologyOutputRedshift[3] = 4.0 CosmologyOutputRedshift[4] = 3.0 CosmologyOutputRedshift[5] = 2.0 CosmologyOutputRedshift[6] = 1.5 CosmologyOutputRedshift[7] = 1.0 CosmologyOutputRedshift[8] = 0.75 CosmologyOutputRedshift[9] = 0.5 CosmologyOutputRedshift[10] = 0.25 CosmologyOutputRedshift[11] = 0.0 # # set hydro parameters # Gamma = 1.6667 HydroMethod = 0 DualEnergyFormalism = 1 // use total & internal energy InterpolationMethod = 1 // SecondOrderA PPMDiffusionParameter = 0 // diffusion off CourantSafetyNumber = 0.5 FluxCorrection = 1 // necessary for mass conservation in AMR ConservativeInterpolation = 0 ParticleCourantSafetyNumber = 0.8 # # set cooling and feedback parameters # RadiativeCooling = 1 // radiative cooling turned on MultiSpecies = 1 // 6-species H+He chem/cooling turned on RadiationFieldType = 2 // Haardt & Madau w/q=-1.8 StarParticleCreation = 2 // star particle creation turned on, using model #2 StarParticleFeedback = 2 // stellar feedback turned on, using model #2 StarMakerOverDensityThreshold = 1000.0 // can create stars when density is this times mean StarMakerMassEfficiency = 0.05 // fraction of gas in cell that can turn into stars StarMakerMinimumMass = 1.0e7 // minimum stellar mass in Msun StarMakerMinimumDynamicalTime = 1.0e+7 // minimum dynamical time in years StarMassEjectionFraction = 0.25 // fraction of star particle mass returned to gas StarMetalYield = 0.02 // fractional metal yield (in mass) StarEnergyToThermalFeedback = 3.0e-6 // portion of star particle rest energy returned as thermal energy # # set grid refinement parameters # StaticHierarchy = 0 // AMR turned on MaximumRefinementLevel = 6 // 6 levels of AMR MaximumGravityRefinementLevel = 6 // gravity calculated on all levels MaximumParticleRefinementLevel = 6 // particle densities not smoothed RefineBy = 2 CellFlaggingMethod = 2 4 // refine on dark matter and baryon mass MinimumEfficiency = 0.35 MinimumOverDensityForRefinement = 8.0 8.0 // refine when cell mass = 8 times original cell mass MinimumMassForRefinementLevelExponent = 0.0 0.0 // refinement is approximately lagrangian # # set some global parameters # GreensFunctionMaxNumber = 100 // # of greens function at any one time