# Infinite homogeneous LWR-like reactor transient example

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Revision as of 17:28, 15 March 2016 by Ville Valtavirta (Talk | contribs) (→Time dependent simulation (0.85$ reactivity insertion))

## Generating the steady state source distributions

set title "Creating source for a time dependent simulation" % --- Geometry is just a cube surf 2 cuboid -100.0 100.0 -100.0 100.0 -100.0 100.0 % --- Cell definitions: cell 3 0 fuel -2 cell 99 0 outside 2 % Outside world % --- Fuel material is a homogenized LWR material: mat fuel sum vol 8.0000E+06 moder lwtr 1001 8016.03c 0.316667 1001.03c 0.633333 92235.03c 0.0015 92238.03c 0.0485 5010.03c 0.000115793 % --- Thermal scattering data for hydrogen in light water (294 K) therm lwtr lwj3.00t % --- Reflective boundary condition: set bc 2 2 2 % --- Set power level set power 1.0 % --- Neutron population: % --- Large population size: (produced approx. 60M neutron and 40M precursor source points) set pop 80000 80000 200 1.0 100 % --- Save neutron and precursor source to "./source"-files set savesrc "./source" % --- Do not generate group constants set gcu -1 % --- Do not use implicit capture, nxn, or fission set impl 0 0 0

## Time dependent simulation (no reactivity insertion)

set title "Time dependent simulation, zero reactivity insertion" % --- Geometry is just a cube surf 2 cuboid -100.0 100.0 -100.0 100.0 -100.0 100.0 % --- Cell definitions: cell 3 0 fuel -2 cell 99 0 outside 2 % Outside world % --- Fuel material is a homogenized LWR material: mat fuel sum vol 8.0000E+06 moder lwtr 1001 8016.03c 0.316667 1001.03c 0.633333 92235.03c 0.0015 92238.03c 0.0485 5010.03c 0.000115793 % 0$ reactivity insertion % --- Thermal scattering data for hydrogen in light water (294 K) therm lwtr lwj3.00t % --- Reflective boundary condition: set bc 2 2 2 % --- Set up time structures for simulation and detectors: % --- 30 time bins for detector tme dettime 2 30 0 3e-3 % --- 1 time interval for simulation (no population control) tme simutime 2 1 0 3e-3 % --- Increase the size of neutron buffer since there is no pop. control set nbuf 10 % --- Neutron population: % --- 300k neutrons in 300 batches (1000 neutrons per batch) set nps 60000000 6000 simutime % --- Link source set dynsrc "../crit/source" 1 % --- Set up detectors: % --- Tally neutron population as a function of time det 1 dr -15 void di dettime % --- Tally fission energy deposition as a function of time det 2 dr -8 void di dettime % --- Save neutron and precursor source to "./source_end"-files set savesrc "./source_end" % --- Do not generate group constants set gcu -1 % --- Do not use implicit capture, nxn, or fission set impl 0 0 0

## Time dependent simulation (0.85$ reactivity insertion)

set title "Time dependent simulation, 0.85$ reactivity insertion" % --- Geometry is just a cube surf 2 cuboid -100.0 100.0 -100.0 100.0 -100.0 100.0 % --- Cell definitions: cell 3 0 fuel -2 cell 99 0 outside 2 % Outside world % --- Fuel material is a homogenized LWR material: mat fuel sum vol 8.0000E+06 moder lwtr 1001 8016.03c 0.316667 1001.03c 0.633333 92235.03c 0.0015 92238.03c 0.0485 5010.03c 0.000113 % 0.85$ reactivity insertion % --- Thermal scattering data for hydrogen in light water (294 K) therm lwtr lwj3.00t % --- Reflective boundary condition: set bc 2 2 2 % --- Set up time structures for simulation and detectors: % --- 30 time bins for detector tme dettime 2 30 0 3e-3 % --- 1 time interval for simulation (no population control) tme simutime 2 1 0 3e-3 % --- Increase the size of neutron buffer since there is no pop. control set nbuf 10 % --- Neutron population: % --- 60M neutrons in 6k batches (10k neutrons per batch) set nps 60000000 6000 simutime % --- Link source (use point-wise precursor tracking) set dynsrc "./source" 1 % --- Set up detectors: % --- Tally neutron population as a function of time det 1 dr -15 void di dettime % --- Tally fission energy deposition as a function of time det 2 dr -8 void di dettime % --- Save neutron and precursor source to "./source_end"-files set savesrc "./source_end" % --- Do not generate group constants set gcu -1 % --- Do not use implicit capture, nxn, or fission set impl 0 0 0