Monigruppidiffuusio

Monigruppidiffuusio, meaning "multi-group diffusion" in English, refers to a computational technique used in various fields, particularly in physics and engineering, to model the simultaneous transport of multiple distinct particle or energy groups. This approach is employed when the behavior of different components within a system cannot be treated as a single, homogeneous entity. For instance, in nuclear reactor physics, it's crucial to track neutrons across different energy ranges (e.g., fast, thermal) and potentially different isotopes, as their interactions and transport properties vary significantly.

The core idea behind monigruppidiffuusio is to solve separate diffusion equations for each defined group. Each group's equation accounts for its own production, absorption, and scattering processes, as well as its coupling to other groups. Coupling typically occurs through scattering, where particles from one group can be scattered into another, or through fission, where neutrons of a certain energy produce new neutrons across various energy groups. This compartmentalization allows for a more accurate representation of complex phenomena that would be oversimplified by a single-group diffusion model. The accuracy of the method depends on the appropriate selection and definition of these groups, which is often based on the physical characteristics and interactions of the particles being modeled. Numerical methods are then applied to solve the system of coupled diffusion equations.