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conferenceseries
.com
Volume 8
Journal of Biotechnology and Biomaterials
ISSN: 2155-952X
Biomaterials 2018
March 05-06, 2018
March 05-06, 2018 | Berlin, Germany
3
rd
Annual Conference and Expo on
Biomaterials
Fabrication of porous materials
Peng-Sheng Wei
National Sun Yat-Sen University, Taiwan
T
he shape of a pore, resulting from a bubble entrapped by a solidification front, is predicted in this work. Porosity influences not
only microstructure of materials, but also contemporary issues of various sciences of biology, engineering, foods, geophysics
and climate change, etc. In this presentation, pore shape is determined by accounting for mass and momentum transport of solute
across a self-consistent shape of the cap, as proposed previously. This work finds that there exist three different mechanisms for pore
formation, depending on different directions and magnitude of solute transfer across the cap. Case 1 is subject to solute transport
from the pore into surrounding liquid as a result of the cap emerged from a thin concentration boundary layer on the solidification
front in the early stage. An increase in initial solute concentration in liquid decreases pore radius and times for bubble entrapment.
Opposite directions of solute transport across the cap submerged into a thick concentration boundary layer along the solidification
front, however, cannot result in bubble entrapment, because solute increases and decreases rapidly in late stage in Cases 2 and 3,
respectively. The predicted pore shape in solid agrees with experimental data. Numerical computations of development of the pore
shape associated with transport processes of fluid flow, temperature and concentration are also presented in Fig. 1.
Fig. 1 Predicted pore shape, and distributions of velocity, temperature and solute concentration fields of two pores at a time of 0.0102 s in Case 1.
Recent publications
1. Wei P S and Chao T C (2016) The effects of drilling parameters on pore size in keyhole mode welding. ASME Journal of
Manufacturing Science and Engineering 138:021008.
2. Wei P S and Chang C C (2016) Existence of universal phase diagrams for describing general pore shape resulting from
an entrapped bubble during solidification. ASME Journal of Heat Transfer 138:104503.
3. Wei P S and Hsiao S Y (2016) Effects of mass transfer coefficient on pore shape in solid. International Journal of Heat
and Mass Transfer 103: 931-939.
4. Wei P S and Hsiao S Y (2016) Effects of solute concentration in liquid on pore shape in solid. International Journal of
Heat and Mass Transfer 103: 920-930.
5. Hsiao S Y and Wei P S (2016) Case study of terrestrial or ambient pressure effects on pore shape in solid. AIAA Journal
of Thermophysics and Heat Transfer 31(4):796-804.
Peng-Sheng Wei, J Biotechnol Biomater 2018, Volume 8
DOI: 10.4172/2155-952X-C1-088