Radiation Shielding & Transport Analysis

Stratify//MHChew is a professional consulting firm specializing in scientific and technical services.

Innovative 3D modeling using the Attila® modeling suite



The safe, effective clean up of our nation's former weapons sites demands high levels of safety and strict compliance. Our expert scientists and engineers use the most advanced methods to determine radiological hazards.  We provide innovative 3D modeling using the Attila® modeling suite, which includes SpaceClaim®, Attila, MCNP6®, and Tecplot 360™.  Using the Attila modeling suite provides significant benefits to clients:
  • Import and mesh client CAD files to speed up MCNP model creation and improve accuracy.
  • Calculate the dose rate at all points in the mesh, not just a few points from traditional MCNP.
  • Use 3-D dose rate results to improve ALARA planning and hazard communication.
  • Propagate photons through thick shields without the trial and error of traditional MCNP.
  • Model large, complex facilities efficiently and accurately for shielding and CAAS applications.
One of our recent clients said of the Attila suite: “Radiological engineering has now caught up to mechanical engineering.”
Radiation Shielding & Transport AnalysisRadiation Shielding & Transport Analysis
An example Attila/MCNP dose rate calculation is shown on the left. A 1000 Ci Cs-137 pinhole irradiator was placed in a room with a maze entrance. SpaceClaim was used to model the entire space, freeing our analysts from solid modeling via antiquated combinatorial geometry. The SpaceClaim model was imported into Attila and meshed in a manner similar to Finite Element Analysis (FEA) for mechanical engineering.

The forward solver in Attila was executed to generate variance reduction data, and MCNP was executed to calculate the dose rate at each mesh point. Visual clues suggest that dose rates by the entry door could be reduced by thickening a portion of the maze wall near the door, providing a cost-effective solution.

Stratify//MHChew's radiation shielding group has a wealth of experience in radiation transport modeling and criticality safety. We employ certified health physicists, physicists, chemists, mathematicians, and disciplined engineers. Some of our staff maintain active US Department of Energy (DOE) “Q” clearances. We are proven radiological consultants working at DOE national laboratories, nuclear power stations, Fukushima, and CERCLA environmental cleanup projects.