Simulation of Laval-Type Nozzle for Applications in Power Generation and Power-to-Electrical Systems

This paper studies the expansion and condensation process of carbon dioxide in the Laval nozzle for power generation and conversion system as key procedures in fluid power to energy transition. Volume of fluid model is first used to simulate the condensation process of CO
2
in Laval nozzle, and the phase transition effects are focused in this study and have been investigated under different inlet conditions near the critical point in the nozzle for related energy conversion procedures, with the inlet temperature range within 306 ~ 328 K and inlet pressure range within 7.0 ~ 8.0 MPa. The results show that condensation in conversion process is more likely to occur under low temperature and high-pressure inlet conditions near the critical point, and when the inlet temperature is constant, the increase of pressure drop caused by the increase of inlet pressure is one of the reasons for accelerating condensation, which allows higher energy conversion rates.