  Self-irradiation damages resulting from fission processes are common
phenomena observed in nuclear fuel containing (NFC) materials. Numerous
$\alpha$-decays lead to local structure transformations in NFC materials. The
damages appearing due to the impacts of heavy nuclear recoils in the subsurface
layer can cause detachments of material particles. Such a behaviour is similar
to sputtering processes observed during a bombardment of the material surface
by a flux of energetic particles. However, in the NFC material, the impacts are
initiated from the bulk. In this work we propose a two-dimensional mesoscopic
model to perform a stochastic simulation of the destruction processes occurring
in a subsurface region of NFC material. We describe the erosion of the material
surface, the evolution of its roughness and predict the detachment of the
material particles. Size distributions of the emitted particles are obtained in
this study. The simulation results of the model are in a qualitative agreement
with the size histogram of particles produced from the material containing
lava-like fuel formed during the Chernobyl nuclear power plant disaster.
