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This paper studies the liquid Nano-droplet production ability using molecular dynamics simulation methodology. The research parameter is performed at the temperature of 310 Kelvin (K), the pressing force of 10.0 × 10−10 Newton (N) and the ejective hole diameters of 25 and 40 Angstrom (Å). The research result shows that liquid Nano-droplets finally were not produced for the ejective diameter of 25 Å. The Nano-jets were not only non-destruction from nozzle’s surface to produce the droplets but also movement downward to come back the nozzle’s surface. The molecular trajectory is very zigzag and curved both inside and outside the ejective container. In the contrary, when increasing the ejective diameter to 40 Å, the liquid Nano-droplet was produced in the same the ejective time and compressible force magnitude. The molecular trajectory is quite straight after ejecting out the outside of the container. Meanwhile, for the nozzle diameter size of 40 Å, the Nano-droplet was not only production but also movement up to leave away the nozzle’s surface under same above conditions. That proves that the ejective diameter has the influences to the moveable direction and Nano-droplets formation ability in the whole ejective process.

During the construction of massive concrete structures, the main factor that affects the structure is temperature. The resulting temperature is the result of hydration of the cement and some other factors, which leads to the formation of thermal cracks at an early age. So, the prediction of temperature history in massive concrete structures has been a very important problem. In this study, with the help of numerical methods, a temperature nomogram was built to quickly determine the maximum temperature in concrete structures with different parameters such as size, cement content, and the initial temperature of the concrete mixture. The obtained temperature nomogram has been compared with the results of the finite element method and the model experiment gives reliable results. It can be used to predict maximum temperature in mass concrete structures to prevent the formation of thermal cracks.

The molecular dynamics is the research method which is used to simulate the liquid ejection in this paper. The factors of 200000 time step (fs) total ejective time of total 200 000 time steps (fs) and various compressible forces of 9.0 × 10−10, 10.0 × 10−10 and 11.0 × 10−10 Newton (N) are main investigated in this research. These influences have action to the moveable direction of fluid jet in the whole ejective process. The research result indicates that liquid jet is prepared to separate out from nozzle plate's surface to form up droplets at the ejective time of 140 000 fs for the nozzle diameter size of 27.5 Angstrom (Å), system temperature of 310 Kelvin (K) and compressible force magnitude of 9.0 × 10−10 (N). However, when increasing the ejective time or compressible force magnitude, the jets were not only non-destruction from nozzle's surface to produce the droplets but also downward movement to go back the nozzle's surface. Meanwhile, with the nozzle diameter size of 40 Å, the droplets are not only production but also movement up to go away the nozzle under same research condition. Those prove that the ejective time and compressible force magnitude have the influences to the moveable direction of fluid jet in the whole ejective process.

This paper studies the water nanojet ejection process using molecular dynamics simulation. The results show that nanoscale water droplets cannot separate from the nozzle plate surface when the nozzle aperture has a diameter of 27.5 Å or smaller. The maximum height of the produced water nanojet is reduced after reaching to its highest position when the jet does not separate from the plate surface. Separation phenomenon between the water nanojet and the nozzle plate surface is the most obvious with the 27.5-Å-diameter nozzle aperture for this simulation setup. In addition, initial findings on the characteristics of nanoscale water droplets (width and contact angle) impinging onto a fixed plate surface are revealed in preparation for future investigation.