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Showing 2 results for Micro Channel
Hassan Kargar Pishbijari, Seyed Jamal Hosseinipour, Hamed Jamshidi Aval,
Volume 15, Issue 10 (1-2016)
Abstract
Metal bipolar plates are key components in fuel cells that are considered as the best alternative to replace graphite plates. Material selection in bipolar plates depends on its weight and corrosion resistance. Metallic bipolar plate can be considered as the best alternative instead of graphite and composite plates. One of the new processes in order to produce this plat is gas blow forming process. In this study, forming of AA8111 bipolar plates with 200 µm thickness in concave groove dies is investigated by gas blow forming process at various pressures (20, 30 and40 bar) and temperatures (300 and 400 ° C). The filling percent of die at various wall angles and depth to width ratios are examined. According to the dimension of channels, maximum and minimum thinning percentage at high temperature and pressure are investigated. Results show that at wall angle of ∝=0, and the depth to width ratio of h/w=0.5, rupture occurs at pressure of 20bar and at temperature of 300° C and at pressures of 20 and 40 bar at temperature of 400° C. The best channel filling with lowest thinning obtained at ∝=15 and h/w=0.5.
F.s. Moghanlou , E. Ghazanfari Jajin, M. Vajdy Hokmabad , Sh. Jafargholinejad ,
Volume 20, Issue 9 (9-2020)
Abstract
The study of micro-scale fluid behavior is known as microfluidics, which has received much attention in many scientific fields. In the current research, the droplet generation in the micro channel has been studied numerically and experimentally. Two micro channels were fabricated by soft lithography method and the results of generated droplets were compared. The process of droplet formation was investigated using two fluids including water (dispersed fluid phase), and oil (continuous fluid phase) at different flow ratios. The images of the droplet formation and crossing steps in the micro channels were analyzed using image processing. The results showed that by increasing the ratio of dispersed to continuous flow, the size of droplets was increased, the droplet formation distance (the distance of the produced droplets) was increased, and the frequency of droplets generation was decreased. Also, the proposed new geometry leads to the production of smaller droplets with higher production frequencies. In the basic geometry, the droplet diameter was observed to be between 117 and 700 micrometers while in the proposed geometry, the diameter of droplets is between 46 and 466 micrometers. In the proposed geometry, the size of the produced droplets decreases, and the production frequency increases.
