List of Abstracts 2018: PLENARY SESSION
Date: May 23, 2018
The primary energy sources for world electricity generation are coal (41%), gas (22%), hydro (16%), nuclear (12%), oil (5%), and renewable (4%). The world electricity demand has doubled between 1990 and 2011 and it is expected to increase up to the year 2035 between 1.7 and 2.5%
per year. One possible way to meet this increasing demand is to increase the efficiency of the present and future coal power plants.
The coal power plants are generally classified into three categories: Supercritical (SC), Ultrasu percritical (USC) and advanced ultra-supercritical (A-USC). SC power plants operate with steam temperature up to 590°C and steam pressure of 250 bar, the USC with 590-620°C and 250 bar, and the A-USC with 700-760°C and 345bar. The world mean efficiency of coal power plants is approximately 36%. This efficiency is achieved by steam temperature lower than 600°C. An increase of the steam temperature to 700-750°C would increase the efficiency up to 50% or more and correspondingly lead to a drop in CO2 emissions that is of utmost importance to reduce global warming. Such conditions require materials with enhanced toughness, creep strength and corrosion resistance. Potential materials for these conditions are ferriticmartensitic, austenitic-steels and nickel-base alloys. Considering the fireside corrosion, the ferritic steels are used up to 620°C and it is expected that in the future these steels will be used up to 650°C. Above these temperatures, the austenitic steels and nickel base alloys have to be used.
Metallurgical processes may typically involve many physical phenomena such as fluid flow, heat transfer, solidification, electromagnetism, chemistry, and kinetics in multi-component multi-phase systems. Permanently growing computational power and a massive shift to parallel cloud computing allow us to design multiphysics numerical simulations and thus gain a deeper insight into fundamental and technical issues. This article overviews up-to-date modeling efforts/achievements in the metallurgical discipline and is not afraid to critically assess current drawbacks as well as to show directions for future developments. The topics concerned are growth and sedimentation of equiaxed crystals, clogging of submerged entry nozzle, thin slab casting, electroslag remelting, electromagnetic stirring in semi-continuous casting, local heat treatment of as-cast structures, and some more.