Speaker: Prof. Chien-Chou Tseng (National Cheng-Kung University, Taiwan)
Title: Applications of two-phase flow models for industrial problems
Abstract:
Two-phase flow models have already been used widely in the industrial application. This talk includes two topics related to the recent progress and development of two-phase flow model in the industry.
(1) Flue Gas Desulfurization (FGD) tower with perforated sieve trays
The CFD simulation based on the Eulerian-Eulerian model has been utilized to a small-scale (FGD) tower with perforated sieve trays. The numerical investigation includes the liquid phase distributions, streamlines of the gas phase, chemical source term, and mass fraction of SO2 gas. The complex vortical structure due to the implement of the sieve trays results in a sufficient large two-phase contact area. It also increases the number of times that the gas phase interacts with the liquid layer above the sieve trays and enhances flow mixing between regions of intense and weak chemical reactions. Correspondingly, the sieve trays can improve the SO2 removal efficiency. This study can help to carry out the numerical based optimal design of the full-scale tower in the future.
(2) Selective laser melting process
The complex evolution of a melt pool of Ti-6Al-4V powder particles under a moving selective laser was studied numerically. A laser power of 175 W and scanning speeds of 850, 1250, and 1650 mm/s were used. An effective laser source term with a time-varying maximum intensity was applied to a representative cross section to simplify the three-dimensional problem into a two-dimensional computational domain. The transport phenomena caused by the Marangoni effect and the inward recoil force contribute to the local suppression of the melt pool. The Marangoni flow conveys the laser energy to the lateral powder, which significantly enhances the wetting phenomenon. This study provides a thorough understanding of the wetting and morphology of the melt pool from a microscopic viewpoint, which could result in detailed design guidelines.
Date: Wednesday, December 12, 2018
Time: 15:00~17:00
Place: Room 103, Mathematics Research Center Building (ori. New Math. Bldg.), NTU
Organizer: Prof. Yi-Ju Chou (Institute of Applied Mechanics, NTU)
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Center for Advanced Study in Theoretical Sciences
Tel: 886-2-3366-9902 (Wei-Jhen Tsai)
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