Effect of ethane on condensation characteristics of methane heterogeneous nucleation: A molecular dynamics study

Clarification on condensation characteristics of alkane gases plays a fundamental role in the development of natural gas liquefaction processes. However, the microscopic condensation characteristics of alkane gas on the heat exchanger wall are still not well understood, which holds significant practical implications for advancing liquefaction technologies. Therefore, this study investigates the microscopic condensation process of heterogeneous nucleation with methane gas through molecular dynamics (MD) simulations. By varying wall energy and ethane content, we analyzed the nucleation kinetic properties of methane heterogeneous condensation. The results demonstrate that high-energy walls enhance heat transfer by enhancing the interaction between wall and methane, thereby accelerating condensation core formation and increasing methane condensation rates. Additionally, increasing ethane content also shortens the time for the formation of condensation cores in methane gas. Ethane has a higher condensation temperature compared to methane, and its presence reduces the difficulty of forming condensation cores in alkane gases and shortens the time for liquid core formation, thus facilitating methane condensation. The above research results will provide new insight for natural gas liquefaction process.