Dose rate calculation

User Support
1

Hi all
This is the geometry of my detector.
det_rect_prism = openmc.model.rectangular_prism(1.3, 1.3, origin=(0.0, 0.0))
det_zmin = openmc.ZPlane(z0=-1.0, boundary_type=‘transmission’)
det_zmax = openmc.ZPlane(z0=+1.0, boundary_type=‘transmission’)

detector = det_rect_prism & +det_zmin & -det_zmax
detector_cell = openmc.Cell(fill= cesium_iodide, region=detector)

I used cesium as a source and put it 5 cm away from the detector.
I want to know the dose rate. Should I write this part of the code like this?

tallies = openmc.Tallies()

dose_tally = openmc.Tally(name=“dose_tally_on_surface”)
dose_tally.scores = [“current”]
dose_tally.filters = [
cell_filter,
photon_particle_filter,
energy_function_filter_p,
]
tallies.append(dose_tally)
model = openmc.model.Model(geometry, materials, settings, tallies)
!rm *.h5
sp_filename = model.run()
import math

on

sp = openmc.StatePoint(sp_filename)

tally = sp.get_tally(name=‘dose_tally_on_surface’)
df = tally.get_pandas_dataframe()

tally_result = df[‘mean’].sum()
tally_std_dev = df[‘std. dev.’].sum()

dose_in_pSv = tally_result / (2*(1.3+1.3+2))

source_activity = 124300 # in decays per second (Bq)
emission_rate = 1
gamma_per_second = source_activity * emission_rate
dose_rate_in_pSv = dose_in_pSv * gamma_per_second
dose_rate_in_μSv=dose_rate_in_pSv*0.0036

I would be very grateful if you could help me.Thank you

2

openmc has some inbuilt dose coefficients than can be used to construct an EnergyFunctionFilter that is then used in the tally.

Here are a few examples of dose tallies on a surface, cell or mesh

3

I wrote a code looking at this example and I compare the dose rates with my experimental results. First, I used cesium and when I adapted the code accordingly, I get almost the same result as the experiment, but when I do it for sodium and barium, there are differences between the results. What could be the reason for this?
Thank you