This chapter considers the methodology and the universal multi–level mathematical model with the possibility of applying to a wide range of problems and technologies for a multidimensional study of the processes of condensation, motion, formation, and interaction of nanostructures. On the basis of a multilevel mathematical model and adapted numerical schemes, a problem–adapted software package with a block–modular structure and with a graphical interactive user interface was created. Numerical simulation of the mechanisms of formation and growth of nanostructures used to feed plants from the gaseous medium has been carried out. The intensity of condensation, the composition and structure of the nanoparticles formed are established. The main properties of nanoelements are calculated. Comprehensive studies of the formation of metal nanoparticles for the technology of thermal evaporation and subsequent condensation under various regimes, compositions, and ratios of parent metals have been performed. The internal structure of nanoobjects is revealed depending on 166the types of raw materials. With the help of statistical analysis, the laws of distribution of the basic properties of nanoclusters are established. The processes of formation of special-purpose aerosol nanostructures used in fire-extinguishing systems have been studied. On the basis of the features of the structure and composition of nanoelements, the possibility of efficient operation of an aerosol gas generator for fire extinguishing in rooms with computer equipment and electrical equipment was tested. The technological process of molecular beam epitaxy on solid substrates has been numerically studied in order to identify various variants of nanostructure formation. A multistage numerical modeling of the formation of nanofilms on porous aluminum oxide matrices by the method of discrete thermal evaporation of powder under high vacuum conditions is carried out. The main dimensional and structural properties of the nanoclusters formed are calculated; the degree of pore filling in the substrates is determined.