Papers by Author: Ya Li Guo

Abstract: The shape and surface texture of a liquid droplet were studied in two-dimension when a droplet impinges on a solid substrate under isothermal condition. The lattice Boltzmann moment model was applied to simulate the fluid dynamics considering the adhesive interaction between fluid particles and surfaces. The results show the influence of wetting on the process and the drop shape. For the hydrophobic surface, the process after impinging may be divided into two stages: the spreading process driven by inertial forces and the subsequent oscillation (recoiling process) driven by surface tension forces. While for the hydrophilic surface, the droplet will only deposits on the surface and there is no the recoiling stage. In addition, the effects of the impinging speed on the shape and texture of the droplet were studied. The spreading speed and the maximum diameter of the spreading droplet increase with the rise of the impinging speed.

Abstract: The ice-temperature storage is one of the most important methods in the preservation of fresh fruits and vegetables, while the theory about ice-temperature storage is still not mature at present. In order to study the effect of the pre-thermal processes and the post-thermal processes on the ice-temperature storage, some experiments were carried out. The experimental conditions included two different cooling rates (5°C/day and 3.5°C /day) and two different heating rates (3.2°C /day and 5.1°C/day). After the cooling, the cooled Kiwi and Pear had been stored in the ice-temperature storage for one month. During the storing time, the total sugar, the acidity and the soluble solid were measured by the national standards each two weeks. The present obtained results show that a lower cooling rate would be beneficial for sustaining hydrocarbons and increasing the acidity in fruits after ice-temperature storage; while a quicker cooling rate would increase the soluble solid in fruits after ice-temperature storage.