The pressure in a perfect gas, being directly proportional to the kinetic energy of the molecules, has a lower bound of zero.

Based on these results, a kinetic model for diamond nucleation in MPCVD system was proposed. The critical gas pressure corresponding to the highest nucleation density was also discussed.

The volute of guide-vane structure can transform the kinetic energy to pressure energy as soon as possible, and improve the capacity of separating gas and liquid for the more balance flow in it.