**4. Conclusions**

**Figure 18.** The bounce domain as water nanodroplets impinge on vibration surfaces. **4. Conclusions**  In this work, molecular dynamics simulation was used to investigate the dynamical **4. Conclusions**  In this work, molecular dynamics simulation was used to investigate the dynamical behaviors of water nanodroplets impinging on the translation surfaces and vibration surfaces. The influences of the translation velocity of the surface, the *We* of water In this work, molecular dynamics simulation was used to investigate the dynamical behaviors of water nanodroplets impinging on the translation surfaces and vibration surfaces. The influences of the translation velocity of the surface, the *We* of water nanodroplets, the vibration amplitudes, and the vibration periods on the dynamical behaviors were investigated. The main conclusions are as follows:

haviors were investigated. The main conclusions are as follows:

behaviors of water nanodroplets impinging on the translation surfaces and vibration surfaces. The influences of the translation velocity of the surface, the *We* of water nanodroplets, the vibration amplitudes, and the vibration periods on the dynamical be-

nanodroplets, the vibration amplitudes, and the vibration periods on the dynamical be-

was developed, which quantitively describes the velocity evolution of water nanodroplets

water nanodroplet and move along the translation direction. At the stable stage, the rota-

water nanodroplet and move along the translation direction. At the stable stage, the rota-

water nanodroplets is, and thus, the asymmetric spreading is more apparent. A higher translation velocity results in the water nanodroplet spreading twice in the direction per-

water nanodroplets is, and thus, the asymmetric spreading is more apparent. A higher translation velocity results in the water nanodroplet spreading twice in the direction per-

nanodroplets, while the increase in vibration periods facilitates it. Additionally, the

nanodroplets, while the increase in vibration periods facilitates it. Additionally, the

(2) At the relative sliding stage, water molecules rotate around the centroid of the

(3) The higher the translation velocity is, the larger the friction force applied to the

(2) At the relative sliding stage, water molecules rotate around the centroid of the

(1) The expression of velocity for water nanodroplets in the direction of translation

(3) The higher the translation velocity is, the larger the friction force applied to the

(4) The increase in vibration amplitudes impedes the spreading of water

(4) The increase in vibration amplitudes impedes the spreading of water

as they impinge on translation surfaces.

as they impinge on translation surfaces.

tion of water molecules disappears.

tion of water molecules disappears.

pendicular to the relative sliding.

pendicular to the relative sliding.

bounce domain of water nanodroplets was mapped.

bounce domain of water nanodroplets was mapped.

(1) The expression of velocity for water nanodroplets in the direction of translation was developed, which quantitively describes the velocity evolution of water nanodroplets as they impinge on translation surfaces.

(2) At the relative sliding stage, water molecules rotate around the centroid of the water nanodroplet and move along the translation direction. At the stable stage, the rotation of water molecules disappears.

(3) The higher the translation velocity is, the larger the friction force applied to the water nanodroplets is, and thus, the asymmetric spreading is more apparent. A higher translation velocity results in the water nanodroplet spreading twice in the direction perpendicular to the relative sliding.

(4) The increase in vibration amplitudes impedes the spreading of water nanodroplets, while the increase in vibration periods facilitates it. Additionally, the bounce domain of water nanodroplets was mapped.

**Author Contributions:** Conceptualization, H.Z. and L.P.; methodology, H.Z. and L.P.; software, H.Z. and X.X.; validation, L.P.; formal analysis, H.Z.; investigation, H.Z.; resources, H.Z.; data curation, H.Z.; writing—original draft preparation, H.Z.; writing—review and editing, H.Z. and L.P.; visualization, H.Z. and X.X.; supervision, L.P.; project administration, L.P.; funding acquisition, L.P. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the National Natural Science Foundation of China (grant number 51875105), the Industry–Academy Cooperation Project of Fujian Province (grant number 2020H6025), and the Scientific Research Program of the Jinjiang Science and Education Park Development Center Fuzhou University, China (grant number 2019-JJFDKY-54).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data related to this investigation are available on reasonable request.

**Acknowledgments:** The authors would like to acknowledge the support from the National Natural Science Foundation of China, the Industry–Academy Cooperation Project of Fujian Province, and the Scientific Research Program of the Jinjiang Science and Education Park Development Center, Fuzhou University, China. The authors also express gratitude to the supercomputing center of Fujian Province, China.

**Conflicts of Interest:** The authors declare no conflict of interest.
