A system, method and software product for simulating inflation of an enclosed volume using gas particles is described. A gas flow characteristics is defined. A group of gas particles is created in the enclosed volume to simulate the injected gas. The average velocity of the gas particles is determined by the temperature and the molar mass of the gas represented by the particles. The gas particles travel through the nozzle into the enclosed volume in random directions. All gas particles are checked for collisions with the boundary and with one another. After detection of a collision, the energy of the particle is transferred either to the boundary or anther particle. The kinetic energy of a gas particle includes a translation and a spinning-plus-vibration component. Only the translation component is transferred to the boundary, while both components are readjusted after a collision between two particles. In addition, the initial balance ratio is restored after a particle-to-particle collision.
