Multi-scenario validation of the robust inversion method with biased plume range and values.

Area of Science:

• Environmental Science
• Atmospheric Science
• Nuclear Engineering

Background:

• Accurate estimation of radionuclide release rates is vital for emergency response and environmental impact assessment.
• Inverse modeling is a common technique but is sensitive to atmospheric dispersion model biases.
• Existing methods struggle with complex scenarios involving dense buildings and varied topography.

Purpose of the Study:

• To investigate the feasibility and performance of the SERACT model.
• To evaluate SERACT's ability to correct plume biases and improve release rate estimation.
• To compare SERACT's effectiveness against Tikhonov-regularized inversion in complex dispersion scenarios.

Main Methods:

• Utilized four wind tunnel experiments simulating complex local-scale dispersion scenarios.
• Replicated environments with dense buildings and heterogeneous topography.
• Compared the performance of the SERACT model against Tikhonov-regularized inversion and its predecessor.

Main Results:

• SERACT successfully corrected modeled plume biases across all four complex scenarios.
• The model simultaneously improved radionuclide release rate estimations, achieving an average deviation of only 5.83% from true rates.
• SERACT-corrected simulations showed superior agreement with measurements, with Pearson correlation coefficients and fractions of data within a factor of 2 significantly outperforming other methods.

Conclusions:

• SERACT is a feasible and effective solution for accurate radionuclide release rate estimation in complex atmospheric dispersion scenarios.
• The model's ability to correct plume biases leads to more reliable environmental consequence assessments.
• SERACT offers a significant advancement over traditional inverse modeling techniques for emergency preparedness.