جستجوی مقالات مرتبط با کلیدواژه « حجم سیال » در نشریات گروه « مکانیک »

In this paper, the phenomenon of liquid drop penetration inside the porous medium is studied by the two-phase fluid volume method. Considering the importance of two-phase and multi-phase flows and achieving the least error in the simulation of this phenomenon, in this research, a model for simulating the two-phase flow of droplet penetration in porous media is proposed, the proposed model has more agreement with experimental results compared with other similar models available in literature, the improvement is the novelty of this paper. The behavior of drop penetration has been predicted by the fluid volume method. The effect of changes in surface tension, viscosity, contact angle, viscosity and permeability and drop spreading level in porous media have been investigated. When the contact angle of the drop is 60 and 20 degrees, the changes of the expansion level are almost the same. The speed of spreading and penetration of water drop without the presence of gravity with surface tension of 0.02 is less than the other two surface tensions of 0.001 and 0.0072, while with the presence of gravity, water droplet with surface tension of 0.001 spreads and penetrates more than the other two cases. The results showed that the fluid volume method used in this research was 9% more accurate than the network Boltzmann method based on the Chan and Shen method with the physics of the same problem compared to the experimental results.

Droplet motion in microchannels is observed in versatile industrial and scientific applications, such as biological engineering, drug delivery, and encapsulation. In current investigation, breakup of mother droplet in a T-junction microchannel is simulated using the Gerris open-source software. To validate current simulation, results are appraised by the published literatures. The comparison depicts that the current results are in good agreement with previous studies. The effect of the presence of a semi-circular obstacle on the flow pattern and the breakup time of mother droplet is investigated for different Capillary numbers (0.006 Ca 0.019) and the non-dimensional initial length of droplet (L*=2, 3, and 4). The results reveal that by simple modifications on the symmetry T-junction, the mother droplet splits faster in the comparison of the ordinary symmetry T-junction geometry under the same conditions. For instance, the breakup time of mother droplet at Ca=0.01 for L*=2, 3, and 4 approximately decreases 75%, 45%, and 32% in the presence of obstacle, respectively. Furthermore, the breakup time of the drop decreases by increasing the Capillary number.