• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1696-1701
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• 2007

This paper presents a micro-mechanical model of ductile fracture for the API X65 steel using the Gurson-Tvergaard-Needleman (GTN) model. Experimental tests and FE damage simulations using the GTN model are performed for smooth and notched tensile bars, from which the parameters in the GTN model are calibrated. As application, the developed GTN model is applied to simulate small-sized, single-edge-cracked tensile and bend bars, via three-dimensional FE damage analyses. Comparison of FE damage analysis results with experimental test data shows overall good agreements.

• Journal of the Korean Institute of Gas
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• v.21 no.4
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• pp.92-102
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• 2017

Fischer-Tropsch synthesis reaction converts syngas (mixture of CO and H2) to valuable hydrocarbon products. Simulation of low temperature Fischer -Tropsch Synthesis reaction and heat transfer at intensified process condition using catalyst filled single and multichannel microchannel reactor is considered. Single channel model simulation indicated potential for process intensification (higher GHSV of $30000hr^{-1}$ in presence of theoretical Cobalt based super-active catalyst) while still achieving CO conversion greater than ~65% and $C_{5+}$ selectivity greater than ~74%. Conjugate heat transfer simulation with multichannel reactor block models considering three different combinations of reactor configuration and coolant type predicted ${\Delta}T_{max}$ equal to 23 K for cross-flow configuration with wall boiling coolant, 15 K for co-current flow configuration with subcooled coolant, and 13 K for co-current flow configuration with wall boiling coolant. In the range of temperature maintained (498 - 521 K), chain growth probability calculated is desirable for low-temperature Fisher-Tropsch Synthesis.